The complete application guide to specifying a Smart-Gear power distribution solution (PDS) E50001-F710-A123-V1-4A00 Answers for energy.
Smart-Gear power distribution solution (PDS) Siemens, a world leader in innovative technologies, has taken another step forward by creating the total solution in medium-voltage, metal-clad switchgear. In response to our customers' need for standard switchgear that is programmable and self-monitoring, Siemens has combined its advanced switchgear, protective relay products and its engineering experience to deliver a total package to customers: Smart-Gear power distribution solution (PDS). With Smart-Gear PDS, users are provided the following features and benefits: Reduced control wiring for increased reliability digital and fiber-optic circuits instead of hard-wired circuits Self-monitoring feature-rich increased operational reliability Programmable easy to implement complex schemes with flexibility for future changes IEC 61850 communication protocol providing integrated control, monitoring and protection Usage-based preventive maintenance notification Faster commissioning and start up. Smart-Gear PDS is equipped with standard self-monitoring features, designed specifically to enhance the performance and reliability of the switchgear. With Smart-Gear PDS, the user is notified in advance of potential problems such as those in trip circuit and space heater circuits. Also, based on the usage of the equipment, the user will be notified when periodic recommended preventive maintenance is needed. Using IEC 61850 communication protocol, all control, monitoring and protection functions are accomplished through a redundant fiber-optic connection between protective relays and bay controllers. This communications capability reduces the need for much of the control wiring necessary to implement and change complex schemes, resulting in reduced field testing and commissioning time. About this guide The purpose of this application guide is to help the reader configure a Smart-Gear PDS switchgear lineup. Each section contains information important in selecting equipment to meet requirements for today s modern medium-voltage switchgear. To make it easy to configure a Smart-Gear PDS switchgear lineup, the various selections in this application guide are presented as building blocks, called application modules. These application modules are described in detail using tables and one-line diagrams. Each section contains information to help the reader determine the power distribution system configuration that best meets their application, protection, operation and overall functionality needs. Please note the information contained in this application guide is a general description of the technical options available for Smart-Gear PDS. Certain features or configurations may not be applicable or appropriate for your specific needs. Nothing contained in this application guide will constitute a warranty or guarantee by Siemens that the Smart- Gear PDS or the configurations described in this guide are fit for your intended purposes. Your local Siemens representative will be happy to assist you with configuring a solution to meet your specific needs. Figure 1: Siemens type GM-SG medium-voltage, metal-clad Smart-Gear PDS switchgear lineup 2
Application-based approach: A new way of specifying switchgear An application-based approach to configuring switchgear offers a new way of thinking. For example, with an application-based approach, all switchgear functions including automatic transfer schemes, circuit breaker types, protection schemes and other special switchgear functions are described in terms of application modules. When combined, these application modules define the operation and configuration of a Smart- Gear PDS solution. All software programs and digital and hard-wired circuits used to perform specific operations or protective functions are referred to as "apps," which are protective relay hardware and software programming (continuous function chart (CFC) programming) designed specifically for application modules. Table of contents Overview 4-5 Smart features 6-8 Application modules 9 System application modules 10-12 Auxiliary application modules 13 Circuit breaker application modules 14-17 Remote control application modules 18 Special application modules 19 Protection functions and metering 20-22 Communications and controls 23-25 Service and support modules 26-28 Instructions for specifying Smart-Gear PDS 29-34 Definitions and terminology 35 Smart-Gear power distribution solution specification form 36-39 3
Overview Smart-Gear PDS is a programmable and self-monitoring power distribution solution that combines Siemens medium-voltage, air-insulated, metal-clad switchgear and Siemens SIPROTEC protective relay technology to offer one of the most advanced standardized switchgear solutions in the industry. With its standard self-monitoring features and programmable capabilities, Smart-Gear PDS redefines how switchgear is specified, engineered, operated, installed and maintained. Feature rich Smart-Gear PDS is rich in standard features, specifically designed to monitor critical functions such as trip circuit integrity, space heater operation, vacuum interrupter wear, circuit breaker status, operations and more. In traditional switchgear, many of these functions and features have to be specified and engineered specifically to the order, but with Smart-Gear PDS these selfmonitoring features are standard. For a list and description of these features and more, refer to the smart features section beginning on page 6. 4
Overview Protective relays and metering Smart-Gear PDS is supplied with the most advanced protective relays in the industry, Siemens SIPROTEC protective relays. These protective relays are fully equipped with the advanced protection functions and Ethernet-based IEC 61850 communications protocol over a redundant fiber-optic cable for high-speed data transmission. Refer to protection functions and metering section beginning on page 20 for a detailed description of the protective relay functions provided with Smart-Gear PDS. For additional details on Siemens SIPROTEC relays, refer to SIPROTEC Numerical Protective Relays Catalog SIP 2008 E50001 K4400- A101-A5-7600 or contact your local Siemens representative. The difference Smart-Gear PDS is equipped with more features and benefits than traditional switchgear. All applicable self-monitoring features, described in the smart features section beginning on page 6, are provided with the standard package. These selfmonitoring features enhance the reliable performance of the equipment. With Smart-Gear PDS, less control wiring is required to implement simple or highly complex control schemes. Communication capability enables interface between protective relays for each circuit breaker, interface with other Smart-Gear PDS switchgear lineups, remote control capability and interface with many SCADA systems deployed with current communication protocols. Simplification from design and specification, to commissioning and operation, is at the heart of Smart-Gear PDS, the intelligent choice in your selection of medium-voltage switchgear. 5
Smart features Smart features - self-monitoring Smart-Gear PDS is provided with standard features designed to monitor the critical functions and controls of the type GM-SG, type GM-SG-AR or type GM38 mediumvoltage switchgear. Options can be selected to increase functionality. The information in this section describes the features in detail. Smart-Gear PDS types Table 1 lists the smart features available for a Smart-Gear PDS switchgear lineup. All of the smart features are available for Smart-Gear PDS type SG-64, while type SG-80 offers slightly fewer choices. Smart-Gear PDS is available in two types: SG-64 and SG-80. The specific functionality of the self-monitoring features are dependent on the Smart-Gear PDS type selected. 3, 4, 5 Table 1: Self-monitoring features Footnotes: 1. Type SG-64 Smart- Gear PDS equipped with type 7SJ6415 protective relays on feeder, main and tie circuit breakers. 2. Type SG-80 Smart- Gear PDS is equipped with type 7SJ8041 protective relays on feeder circuit breakers and type 7SJ6415 protective relays on main and tie circuit breakers. 3. MOC and TOC not required for remote control and monitoring using communications when HMI is provided. 4. Circuit breaker operation provided through protective relays. Control switches are not provided. 5. All functions are available via Intelligent Electronic Device (IED) Siemens protective relay. 6. Standard for type 7SJ6415 protective relays furnished on main circuit breakers. Features available via protective relay devices Type SG-64 1 Type SG-80 2 Circuit breaker operating cycles monitoring Standard Standard Circuit breaker trip-circuit monitoring Standard Standard Circuit breaker close-circuit monitoring Standard Not available 6 Vacuum interrupter wear monitoring Standard Standard Integrated controls Standard Standard Circuit breaker racking position indication Standard Not available 6 Integrated power monitoring Standard Standard Programmable circuit breaker control interlocking Optional Optional Programmable main-tie-main transfer scheme Optional Optional Fan cooling monitoring for 4,000 A circuit breaker 7 Standard Not available 6 Voltage transformer monitoring Standard Standard Current transformer monitoring Standard Standard Bus protection (device 50B) Standard Standard Space heater operation monitoring Standard Standard Large protective relay display screen Standard Not available 6 IEC 61850 communication protocol (only) Standard Standard Arc-flash detection Optional Optional 7. 4,000 A for types GM-SG and GM-SG-AR switchgear up to 15 kv; 3,000 A for type GM38 switchgear up to 38 kv. 6
Smart features Standard features Circuit breaker operating cycles monitoring This smart feature alerts the user when the drawout circuit breaker is approaching its pre-set threshold of operating cycles for scheduled maintenance. The threshold is pre-set at the factory to provide advance notification at 80 percent usage (20 percent of the remaining operations) of the recommended operations cycle. Trip-circuit monitoring In the event of a fault, the user needs confidence that the circuit breaker trip circuit will open the circuit breaker. This feature monitors the integrity of the trip circuit and provides the user notification of non-functionality of the trip circuit resulting from failed trip coil or blown tripcircuit fuse. Close-circuit monitoring (type SG-64 only) Monitoring the status of the close circuit is critical in cases where transferring and redirecting power is required, such as with a main-tie-main automatic transfer scheme. This feature monitors the integrity of the close circuit and provides the user notification of non-functionality of the close circuit resulting from a failed close coil or blown close-circuit fuse. Vacuum interrupter wear monitoring This smart feature monitors the remaining expected life of the vacuum interrupters by calculating the accumulated load, no-load and short-circuit interruption data. Based on the calculation, the user is given notification of vacuum interrupter contact wear. Means for visual verification of the vacuum interrupter during circuit breaker inspection is standard. Circuit breaker racking position indication (type SG-64 only) The position status of the circuit breaker is connected to binary inputs on the protective relay, and is thus available for local and remote monitoring and control logic. The circuit breaker positions include connected, disconnected and test. Integrated controls Two things visibly different about Smart- Gear PDS compared to traditional switchgear are fewer control devices and significantly less control wiring. With Smart-Gear PDS, the circuit breaker control switch function (CS) and lockout protective relay function (86) are an integral part of the protective relay. Having these control functions in the protective relay enables the user to change control logic electronically without having to change the hard-wired circuitry. Integrated power monitoring Main, feeder and tie circuit breakers are equipped with integrated power metering (one percent accuracy) including current, voltage and power measurement functions. Current measurements include Ia, Ib, Ic, min/max and min/max current demand. Voltage measurements include phase voltages and min/max. Power measurements include peak demand kw, peak demand kvar and peak demand kva, min/max power factor, min/max frequency, set-points and pulse counter. Min/max data also includes date and time. Programmable circuit breaker control interlocking (optional) Continuous function chart (CFC) programming software makes digital circuit breaker interlocking available for a Smart-Gear PDS. This technology enables interlocking of multiple circuit breakers in the lineup, enabling user modification without complicated and timely wiring changes and retesting. All interunit connectivity between circuit breakers is through IEC 61850 communication protocol over redundant fiber-optic connections. Figure 2: Siemens type GM38 medium-voltage, metal-clad Smart- Gear PDS switchgear lineup 7
Smart features Voltage transformer monitoring Three-phase, wye-connected (required) voltage transformers are monitored for proper operation including blown fuse and voltage transformer failure. As with other event data, this information is retained in the protective relay ready for local and remote monitoring. Current transformer monitoring Current transformers are monitored for proper phase and current summation. Information is retained in the protective relay ready for local and remote monitoring. Bus protection (device 50B) Reverse-zone interlocking is used to distinguish a bus fault from a through-fault and uses IEC 61850 generic object oriented substation event (GOOSE) messaging. Space heater operation monitoring Programmable main-tie-main transfer scheme (optional) CFC programming software makes digital implementation of automatic transfer schemes available for Smart-Gear PDS. Like the programmable circuit breaker interlocking feature, this feature enables the user to modify the scheme without complicated and time-consuming wiring changes and retesting. All interunit connectivity between circuit breakers is with redundant fiber-optic connections. Fan cooling monitoring for fan-cooled circuit breakers (type SG-64 only) This feature monitors the cooling fan for a 4,000 A circuit breaker (in types GM-SG and GM-SG-AR switchgear up to 15 kv) or 3,000 A circuit breaker (in type GM38 switchgear up to 38 kv). The cooling fan air-flow switch provides the input signal to the protective relay for local and remote monitoring. Arc-flash detection (optional) Arc-flash detection is available with Smart- Gear PDS. Space heater functionality is important for long-term operation and reliability of switchgear, particularly under conditions of high humidity or in outdoor applications. Many switchgear failures result from improper use of space heaters including instances in which the space heaters were not energized or were never wired to the power source. With Smart- Gear PDS, the operation of the space heaters is under constant monitoring to improve the long-term reliability of the power distribution system. Large display (type SG-64 only) A large display screen is provided with the Siemens SIPROTEC type 7SJ6415 protective relay solution and is provided for all main circuit breakers. IEC 61850 enabled Each protective relay is equipped with IEC 61850 communication protocol. More information on IEC 61850 is included in the communications and controls section beginning on page 23. 8
Application modules Application modules This guide uses an application-based approach described on page 3 to configuring Smart-Gear PDS. All automatic transfer schemes, interlock schemes, circuit breaker types, protection schemes, remote control solutions and interfaces, paralleling solutions and other special applications are described in Smart- Gear PDS as application modules. Application modules are the building blocks used for configuring a Smart-Gear PDS switchgear lineup. These modules are pre-configured applications designed to perform specific functions. There are five classes of application modules: 1. System application modules Automatic transfer Circuit breaker interlocking Protection 2. Auxiliary application modules Voltage transformer Control power transformer 3. Circuit breaker application modules Main circuit breaker Tie circuit breaker Feeder circuit breaker 4. Remote control application modules SIPROTEC CBII controller Local human machine interface (HMI) SICAM station unit/pas Remote electric racking 5. Special application modules Partial discharge Arc-flash detection Transformer assets. System application modules System application modules are used to define the operation and protection of the entire switchgear lineup. All automatic transfer and circuit breaker interlock application modules are implemented with CFC programmed protective relays, IEC 61850 communications over fiber-optic cable. Tables 2, 3 and 4 on pages 10-12 describe these system application modules in detail. Automatic transfer application modules With Smart-Gear PDS, four types of automatic transfer application modules are offered. These digital automatic transfer schemes are configurable for automatic or manual restore, open- or closed-transition and preferred or non-preferred sources. Refer to the definitions and terminology section on page 31 for detailed descriptions of these terms. The available automatic transfer application modules are described in Table 2 on page 10. All time delays and timing will be determined at the engineering stage. 9
System application modules Automatic transfer system application modues Table 2: Automatic transfer application modules Selective automatic transfer application modules Apps Automatic transfer No preferred source Preferred source Automatic restore Manually restore Open transition Closed transition Main-tie-main AT1-1 Available Available ---- 1 ---- 1 Available ---- 1 Available AT1-2 Available Available ---- 1 ---- 1 Available Available ---- 1 AT1-3 Available Available ---- 1 Available ---- 1 Available ---- 1 M ATS M T AT1-4 Available Available ---- 1 Available ---- 1 ---- 1 Available AT1-5 Available ---- 1 Available Available ---- 1 Available ---- 1 AT1-6 Available ---- 1 Available Available ---- 1 ---- 1 Available Main-main AT3-1 Available Available ---- 1 ---- 1 Available ---- 1 Available AT3-2 Available Available ---- 1 ---- 1 Available Available ---- 1 AT3-3 Available Available ---- 1 Available ---- 1 Available ---- 1 M M AT3-4 Available Available ---- 1 Available ---- 1 ---- 1 Available ATS AT3-5 Available ---- 1 Available Available ---- 1 Available ---- 1 AT3-6 Available ---- 1 Available Available ---- 1 ---- 1 Available Footnote: 1. ---- 1 means this offering is not available. Other configurations are available. Please consult factory. 10
System application modules Circuit breaker interlocking application modules Circuit breaker interlocking is easily accomplished with CFC programmed protective relays. Digital circuit breaker interlocking schemes are categorized in Table 3 as sequential or selective circuit breaker interlocking. All time delays and timing will be determined at the engineering stage. Table 3: Circuit breaker interlock application modules Selective circuit breaker interlock application modules Circuit breaker-circuit breaker interlocking F I F Circuit breaker-remote circuit breaker interlocking F I R Apps Name Application description BI1 BI2 BI3 RBI1 RBI2 RBI3 Circuit breaker transfertrip interlock Circuit breaker interlock Circuit breaker trip-close interlock Remote circuit breaker transfertrip interlock Remote circuit breaker interlock Remote circuit breaker trip-close interlock This interlock scheme is programmed to transfer the tripping event between two circuit breakers. Circuit breakers are digitally interlocked using CFC programming so a tripping event of either circuit breaker will trigger the tripping event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain the trip state (unless manually actuated) until normal conditions are restored. Options for this application include time delay and multiple circuit breaker interlocking. This interlock scheme is programmed to initiate the closing event between two circuit breakers. Circuit breakers are digitally interlocked using CFC programming so a closing event of either circuit breaker will initiate the closing event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain the same trip or closed states (unless manually actuated) under normal and abnormal conditions. Options for this application include time delay and multiple circuit breaker interlocking. This interlock scheme is programmed so the tripping event of a circuit breaker will initiate the closing event of the other interlocked circuit breaker. Circuit breakers are digitally interlocked via CFC programming so a tripping event of either circuit breaker triggers the closing event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain opposite states (unless manually actuated). Options for this application include time delay and multiple circuit breaker interlocking. This interlock scheme is programmed to transfer the tripping event between two circuit breakers. Circuit breakers are digitally interlocked using CFC programming so a tripping event of either circuit breaker will trigger the tripping event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain the trip state (unless manually actuated) until normal conditions are restored. Options for this application include time delay and multiple circuit breaker interlocking. This interlock scheme is programmed to initiate the closing event between two circuit breakers. Circuit breakers are digitally interlocked using CFC programming so a closing event of either circuit breaker will initiate the closing event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain the same trip or closed states (unless manually actuated) under normal and abnormal conditions. Options for this application include time delay and multiple circuit breaker interlocking. This interlock scheme is programmed so the tripping event of a circuit breaker will initiate the closing event of the other remote interlocked circuit breaker. Circuit breakers are digitally interlocked via CFC programming so a tripping event of either circuit breaker triggers the closing event of the other interlocked circuit breaker. Note: Interlocked circuit breakers will maintain opposite states (unless manually actuated). Options for this application include time delay and multiple circuit breaker interlocking. 11
System application modules Protection application modules Three protection application modules have been defined in this section for Smart- Gear PDS. These application modules are described in Table 4. Table 4: Protection application modules Protection application modules Zone selective interlock Apps Name Application description OC M IEC 61850 GOOSE F F ZSI Zone selective interlock This application module is a cost-effective alternative to the 87B App. Zone selective interlocking, provides high-speed bus protection and involves selective blocking of the high-speed overcurrent protection on the incoming main if any of the feeder overcurrent relays are in pickup. If a fault is not present on any of the load feeders, the incoming main high-speed overcurrent protection is not blocked, providing high-speed and selective protection for bus faults. Bus differential protection (traditional) 87B M F F 87B Bus differential protection (traditional) This bus differential protection scheme is performed using a Siemens protective relay. Each circuit breaker application module will be equipped with bus differential current transformers. Transformer differential protection 52 87T-2W Twowinding transformer differential protection This transformer differential protection application for a two-winding transformer includes an 87T protective relay using Siemens type 7UT612. The application module is used for an incoming transformer circuit breaker or for a transformer distribution feeder circuit breaker. 87T 52 87T-3W Threewinding transformer differential protection This transformer differential protection application for a three-winding transformer includes an 87T protective relay using Siemens type 7UT613 relay. The application module is used for an incoming transformer circuit breaker or a transformer distribution feeder circuit breaker. 12
Auxiliary application modules Auxiliary application modules Auxiliary application modules are defined by the type of auxiliary device in the compartment and their configuration. There are four basic auxiliary application modules. These application modules cover typical voltage transformers and control power transformers usage. Table 5 provides a list of the auxiliary application modules available for configuring a Smart-Gear PDS switchgear lineup. Figure 3: 38 kv primary current limiting fuses accessible when fuse truck in disconnect position with access door open Table 5: Auxiliary application modules Auxiliary application modules Line connected voltage transformer MB Fuse Three VTs Apps Components list Application description LVT Three voltage transformers (VTs) Three primary current limiting fuses (CLF) Drawout tray Three secondary fuses The line connected VTs are connected in a wye-wye configuration. The 120 Vac secondary voltage signal is used for protective relays and metering. Main bus connected voltage transformer Fuse Three VTs Three VTs MB BVT Three primary CLF Drawout tray Three secondary fuses The main bus connected VTs are connected in a wyewye configuration. The 120 Vac secondary voltage signal is used for protective relays and metering. Line connected control power transformer MB LCPT 15 kva control power transformer (CPT), single phase, 120/240 Vac secondary Two primary CLF Drawout tray The line connected CPT is used for powering auxiliary loads, such as switchgear space heaters, battery chargers, lighting and other auxiliary devices. Fuse CPT Secondary molded-case circuit breaker Bus connected CPT Fuse CPT MB BCPT 15 kva control power transformer (CPT), single phase, 120/240 Vac secondary Two primary CLF Drawout tray The line connected CPT is used for powering auxiliary loads, such as switchgear space heaters, battery chargers, lighting and other auxiliary devices. Secondary molded-case circuit breaker 13
Circuit breaker application modules Circuit breaker application modules Circuit breaker application modules are defined by the functional requirement (or load type) of a circuit breaker. For Smart- Gear PDS, there are eight basic circuit breaker application modules. These application modules include main, tie, motor feeder, transformer feeder, distribution feeder and capacitor feeder applications and equipped space or future cell modules. Each circuit breaker application module (except future cell) is fully equipped with the relay protection necessary to meet the protection requirements of the specific application and functions of the circuit breaker (refer to protection functions and metering section starting on page 20 for additional details on the protective functions of each circuit breaker application module). Note: For Smart-Gear PDS type SG-64, all main, tie and feeder circuit breakers are equipped with the Siemens type 7SJ6415 protective relays. For the Smart-Gear PDS type SG-80, all feeder circuit breakers are equipped with the Siemens type 7SJ80 (or type 7SK80 for motor applications) protective relays, while all main and tie circuit breakers are equipped with Siemens type 7SJ6415 protective relays. Table 6 on pages 15-17 provides a complete list of the circuit breaker application modules available for configuring a Smart-Gear PDS switchgear lineup. Type GMSG 5 kv-15 KV circuit breaker for use in types GM-SG or GM-SG-AR switchgear Type 38-3AH3 38 KV circuit breaker for use in type GM38 switchgear Figure 4: Siemens circuit breakers 14
Circuit breaker application modules Table 6: Circuit breaker application modules (continued) Circuit breaker application modules Main circuit breaker MB Tie circuit breaker TB Distribution feeder DB L L L Apps MB1 TB1 DFB1 or plus Components list One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear One Siemens type 7SJ6415 protective relay Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Three line-connected voltage transformers (LVTs) Fiber-optic cable One "smart features" package (refer to smart features on page 6) Optionally availble for this module is a line-connected or bus-connected CPT (refer to auxiliary application modules on page 13 for details). or plus or plus One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear One Siemens type 7SJ6415 protective relay Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Fiber-optic cable One "smart features" package (refer to smart features on page 6). One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear One Siemens type 7SJ6415 protective relay for Smart-Gear PDS type SG-64 or one Siemens type 7SJ8041 protective relay for Smart-Gear PDS type SG-80 Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Fiber-optic cable One "smart features" package (refer to smart features on page 6). 15
Circuit breaker application modules Table 6: Circuit breaker application modules (continued) Circuit breaker application modules Motor feeder MB M Transformer feeder TB Capacitor switching CB Apps MFB1 TFB1 CB1 or Components list One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear plus One Siemens type 7SJ6415 protective relay for Smart-Gear PDS type SG-64 or one Siemens type 7SJ80 protective relay for Smart-Gear PDS type SG-80 or plus or plus Two Siemens SIPROTEC RTU boxes (12 RTDs standard) Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgears Fiber-optic cable One "smart features" package (refer to smart features on page 6). One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear One Siemens type 7UT61 protective relay for transformer differential protection One Siemens type 7SJ6415 protective relay for Smart-Gear PDS type SG-64 or one Siemens type 7SJ8041 for Smart-Gear PDS type SG-80 Six standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Fiber-optic cable One "smart features" package (refer to smart features on page 6). One Siemens type GMSG vacuum circuit breaker 1,200 A, 2,000 A, 3,000 A or 4,000 A@ 4.76 kv, 8.25 kv or 15.0 kv, up to 63 ka for type GM-SG or up to 50 ka for GM-SG-AR switchgear One Siemens type 38-3AH3 vacuum circuit breaker 1,200 A, 2,000 A or 3,000 A@38.0 kv up to 40 ka for type GM38 switchgear One Siemens type 7SJ6415 protective relay for Smart-Gear PDS type SG-64 or one Siemens type 7SJ80 for Smart-Gear PDS type SG-80 Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Fiber-optic cable One "smart features" package (refer to smart features on page 6). 16
Circuit breaker application modules Table 6: Circuit breaker application modules (continued) Circuit breaker application modules Equipped space RLY Apps EQP Components list One Siemens protective relay selected based on the circuit breaker application module Three standard accuracy CTs type MD for types GM-SG or GM-SG-AR switchgear or type MD38 for type GM38 switchgear Fiber-optic cable One "smart features" package (refer to smart features on page 6). Future cell FUT One set of primary stabs for 1,200 A, 2,000 A, 3,000 A or 4,000 A (Note: 4,000 A rating available for types GM-SG and GM-SG-AR switchgear only) One circuit breaker racking mechanism, secondary disconnects, interlocks, etc., ready for future installation of a circuit breaker. Figure 5: Siemens type GM-SG-AR medium-voltage, metal-clad Smart-Gear PDS switchgear lineup 17
Remote control application modules Remote control application modules Remote control application modules are optional upgrade modules available for a Smart-Gear PDS switchgear lineup and are designed to optimize the operational safety by providing various remote control solutions. Table 7 describes the remote control options available for a Smart-Gear PDS switchgear lineup. Figure 6: Siemens SICAM PAS CC Table 7: Remote control application modules Remote control application modules Apps Components list Application description CBII controller CBII Siemens SIPROTEC CBII controller Local HMI SICAM station unit/pas HMI PAS Siemens type MP370 15" touch screen panel PC Siemens SICAM PAS CC Siemens SICAM PAS station unit Siemens PAS CC The Siemens SIPROTEC CBII controller is a cost-effective solution that enables remote operation of the circuit breakers. This eliminates the need for the user to operate the switchgear while standing in front each circuit breaker. Normal operations, including opening, closing and obtaining metering data, can be performed without having to stand directly in front of the switchgear. Local HMI visualization system is scalable for low and high functionalities. Available with an XGA resolution (1,024 x 768 pixels) touch screen with 256 colors for pixels and 16 colors for text. With local HMI, the user can operate the circuit breakers via the protective relays, can display status and real time values of all protective relays/circuit breakers and can view a single-line diagram with dynamic graphics showing status of the power system and the circuit breakers. This module reduces incident energy exposure by moving the operator away from the front of a circuit breaker. Siemens SICAM station unit/pas provides low hardware and software costs, scalability and flexibility, in an easy-to-use communications platform with powerful real-time data distribution capability. Siemens SICAM PAS CC is a scalable processor visualization system. Siemens SICAM PAS station unit supports a large number of established protocols enabling interoperability. 18
Special application modules Special application modules Special application modules are available as optional upgrades for Smart-Gear PDS. These special application modules are designed to enhance the operability and improve the reliability and performance of the switchgear. Table 8 describes the special application modules available with your Smart-Gear PDS selection. Footnote: 1. Self-monitoring network - all inputs into the protective relays or optional HMI system for monitoring. Table 8: Special application modules Special application modules Apps Components list Application description Partial discharge PD1 Partial discharge system installed and factory tested The partial discharge system solution monitors partial discharge activity thereby increasing the reliability of the switchgear. The partial discharge system provides signal input to Smart-Gear PDS self-monitoring network 1 for local or remote monitoring. Arc-flash detection AF1 Arc-flash detection system installed and factory tested Arc-flash detection uses protective relays to sense the occurrence of an arcing event inside the switchgear, and initiates tripping of all circuit breakers connected to the affected section of the switchgear. The system can also initiate tripping of remote power sources. The arc-flash detection system provides a signal input to Smart-Gear PDS self-monitoring network for local or remote monitoring. 19
Protection functions and metering Protection functions and metering With Smart-Gear PDS, protection and metering functions are pre-defined based on the specific application of the circuit breaker and, because of this, the process of configuring circuit breakers is easy. All protective relays used for each circuit breaker application module are equipped with the IEC 61850 communication protocol. Table 9 describes the protection and metering functions that are standard or optional for each circuit breaker application module. Table 9: Protection functions and metering ANSI Functions Application Main Tie Feeder Main Tie Motor Distribution Transformer Capacitor 14 Locked rotor ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 21 Distance protection phase ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 21FL Fault locator Standard Standard ---- 1 Standard Standard Standard 24 25 Overfluxing (V/ Hz protection) Synchronizing, synchronism check ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Optional 2 Optional 2 ---- 1 ---- 1 ---- 1 ---- 1 27 Undervoltage Standard Optional Standard Standard Standard Standard 32 Directional power Standard Optional Standard Standard Standard Standard 32F Forward power Standard Optional Standard Standard Standard Standard 32R Reverse power Standard Optional Standard Standard Standard Standard 37 Undercurrent or underpower Standard Optional Standard Standard Standard Standard 40 Loss of field ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 46 47 48 Load unbalance, negative, phasesequence, overcurrent Phase-sequence voltage Motor starting protection Standard Optional Standard Standard Standard Standard Standard Optional Standard Standard Standard Standard ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 49 Thermal overload ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 20
Protection functions and metering Table 9: Protection functions and metering (continued) ANSI 49R 49S 50 50N 50BF 50GN 51 51N 51M 51V 59 59N 59GN 64 64R 67 67N 67G 68 74TC 78 Functions Rotor thermal protection Stator thermal protection Instantaneous overcurrent Instantaneous ground overcurrent Circuit breaker failure Zero speed and under speed Overcurrent time, phase Overcurrent time, ground Load jam protection Overcurrent time relay, voltage controlled Overvoltage protection Residual voltage ground fault Stator ground fault protection 100% stator ground faul protection Rotor ground fault Directional overcurrent Directional ground overcurrent Stator ground directional overcurrent Power swing detection Trip circuit monitoring Out-of-step protection Application Main Tie Feeder Main Tie Motor Distribution Transformer Capacitor ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 Standard Optional Standard Standard Standard Standard Standard Optional Standard Standard Standard Standard Standard Optional Standard Standard Standard Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Standard Optional Standard Standard Standard Standard Standard Optional Standard Standard Standard Standard ---- 1 ---- 1 Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Standard Optional Standard Standard Standard Standard Standard Optional Standard Standard Standard Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Standard Optional ---- 2 Standard Standard Standard Standard Optional Standard Standard Standard Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Standard Optional ---- 1 ---- 1 ---- 1 ---- 1 Standard Optional Standard ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 21
Protection functions and metering Table 9: Protection functions and metering (continued) ANSI Functions Application Main Tie Feeder Main Tie Motor Distribution Transformer Capacitor 79 Auto-reclosure Standard Standard Standard ---- 1 ---- 1 ---- 1 81IO/U 81R Under-/overfrequency Rate-offrequencychange protection Standard ---- 1 ---- 1 ---- 1 ---- 1 --- 1 Standard Optional Standard ---- 1 ---- 1 --- 1 86 Lockout Standard Optional Standard ---- 1 ---- 1 ---- 1 87G 87T 87B 87M 87N Differential protection generator Differential protection transformer Differential protection bus Differential protection motor Differential protection ground Metering and other functions ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Optional ---- 1 ---- 1 ---- 1 Optional ---- 1 Optional ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 ---- 1 Optional ---- 1 ---- 1 ---- 1 Optional ---- 1 Optional ---- 1 Optional Optional Application Main Tie Feeder Main Tie Motor Distribution Transformer Capacitor Energy metering values W p, W q Standard Standard Standard Standard Standard Standard Slave pointer Standard Standard Standard Standard Standard Standard Eight oscillographic fault records Service interface for Siemens DIGSI 4 (modem) Standard Standard Standard Standard Standard Standard Standard Standard Standard Standard Standard Standard Footnotes: 1. ---- 1 means this offering is not available. 2. Standard for Smart-Gear PDS type SG-64 and not available for Smart-Gear PDS type SG-80. 22
Communications and controls Because IEC 61850 is the global standard for substation automation communication protocol, it is the standard communication protocol used for Smart-Gear PDS. IEC 61850 communicates over TCP/IP networks and/or substation LANs using high-speed switched Ethernet (baud rate is 100 Mbps). It can be mapped to the most wellestablished protocols, including GOOSE or peer-to-peer messaging and Web services. Since IEC 61850 is an open protocol that supports communication for monitoring, control and protection functions, it offers significant advantages for interfacing among circuit breakers within a lineup as well as other devices throughout the power distribution system. All Siemens type SIPROTEC protective relays used in Smart-Gear PDS are equipped for IEC 61850 communications. The automatic transfer and circuit breaker interlock schemes described in system application modules beginning on page 10 are achieved through continuous function chart (CFC) programming, and initiated by the protective relays through IEC 61850 GOOSE messaging communication. This digital capability significantly reduces the number of control wires, especially interunit (wiring between sections) control wiring. There are three communication and control application modules, including local control, remote-local control and remote control application. Each control and monitoring module is a building block for configuring an advanced communications network, in which the local control and monitoring are the foundation for all other control and monitoring modules. 23
Communications and controls GOOSE messaging/peer-to-peer IEC 61850 Redundant fiber-optic connectivity Input/output connections MB TB MB Figure 7: Extended Smart-Gear PDS network Smart-Gear PDS network: local control and monitoring Local control and monitoring is accomplished among the Siemens type SIPROTEC protective relays within the Smart-Gear PDS switchgear lineup. The protective relays are pre-programmed using Siemens DIGSI 4 software to meet the specific application requirements, including automatic transfer schemes and circuit breaker interlock schemes as described in system application modules on pages 10-12. For Smart-Gear PDS, local operation and control (closing and opening) of the circuit breakers is accomplished through the protective relay circuit. All automatic transfer, circuit breaker interlocking and lockout functions are accomplished through protective relays within the local digital network. The interface among circuit breakers is accomplished with CFC programming, IEC 61850, peer-to-peer/goose messaging and fiber-optic connections. The input/ output between a protective relay and a circuit breakers is hard-wired. Main-tie-main automatic transfer schemes are accomplished with GOOSE messaging and CFC programming, which is a more reliable and flexible approach to system automation. Extended Smart-Gear PDS network: local/remote communication and controls Local/remote communication and controls are accomplished using IEC 61850 over dual fiber-optic connection. This system retains all of the functions and capabilities of the remote control application modules described on page 18 while enabling remote monitoring and control of the Smart-Gear PDS switchgear lineup. Through the touch screen panel PC (HMI interface) or the type SIPROTEC CBII controller, the operator has complete control of the lineup to remotely view the status and operate each circuit breaker. The touch screen panel PC or type SIPROTEC CBII controller can be located remotely or close to the Smart-Gear PDS switchgear lineup (refer to remote control application modules on page 18 for details on capabilities of the local HMI and type SIPROTEC CBII controller). Extended Smart-Gear PDS network: interface with new and existing power management systems Remote communication and controls with interface capability to new or existing systems is accomplished using IEC 61850 protocol. This system has all of the functions and capabilities as the local control and monitoring module, described on page 28, as well as the remote enhancement described above. This provides the ability to interface with existing systems, including SCADA and building management systems (BMS). Because the SICAM station unit used in this application supports a large number of established protocols, the self-monitoring data and control functions capability from the Smart-Gear PDS local network is available to other systems, thus providing a seamless integration into existing networks. 24
Communications and controls GOOSE messaging/peer-to-peer IEC 61850 Redundant fiber-optic connectivity Standard local controls Local remote control upgrade Input/output connections MB TB MB HMI visualization system scalable for low/high functionality Figure 8: Extended Smart-Gear PDS network with local HMI GOOSE messaging/peer-to-peer IEC 61850 Redundant fiber-optic connectivity Standard local controls Local remote control upgrade Input/output connections MB MB Type SIPROTEC CBII controller TB Figure 9: Extended Smart-Gear PDS network with SIPROTEC type CBII controller GOOSE messaging/peer-to-peer IEC 61850 Redundant fiber-optic connectivity Standard local controls Local remote control upgrade Input/output connections MB TB MB SICAM controller interface with existing system Figure 10: Extended Smart-Gear PDS network with SIPROTEC type CBII controller 25
Service and support modules Features and functionality Delivery module Programming and customization Dedicated project management Bench testing IEC 61850 technology lab Customer witness testing Training Field service and commissioning Table 10: Service and support modules Delivery module Standard cycle On-board approval drawings Certified cycle Apps SA OBA Table 11: Approval drawing cycle modules C Description Availability Optional Optional Standard Standard Optional Optional Optional Standard approval drawings are provided with this order process (longest delivery cycle). Customer approval drawings review process conducted at the Siemens facility (shorter delivery cycle). Customer approval drawings review waived. No approval drawings are provided (shortest delivery cycle). Service and support modules Several standard and optional service modules are available with Smart-Gear PDS. This section provides a list of these service modules. Table 10 describes each service module designed to fit the specific needs and requirements of a project. Approval drawing cycle modules This module is structured to meet the specific delivery requirements of a project. Table 11 provides a list of the approval drawing cycle modules. Programming and customization module All of the automatic transfer application modules and circuit breaker interlock application modules (refer to page 10-12) are pre-programmed to perform specific functions. While most of the required functions are included for each transfer module, customization of the modules is also available. With Smart-Gear PDS, the user has the flexibility to customize the protective relay programming to meet almost any special requirement. Any application module can be customized to meet specific needs simply by providing a detailed description of the modification to the automatic transfer and circuit breaker interlock application module. Dedicated project management For all Smart-Gear PDS orders, dedicated project management will be assigned to manage the order from beginning to end. This provides the Smart-Gear PDS customer a single point of contact for all technical, contract and production questions. This single point of contact helps ensure that the customers receive fast and comprehensive responses to their questions. 26
Service and support modules Technical training Siemens offers training to keep customers up-to-date on the latest technologies and changes in the power distribution industry. These training classes are tailored to the unique needs of each customer, and focus on application training for engineering, testing and operations personnel. Protective relay training is available and is intended for protective relay engineers, designers and technicians from electric utilities and industrial firms wishing to gain a basic knowledge of the planning, commissioning and maintenance of system protection equipment. Training is also available for Siemens DIGSI software and is intended for protective relay engineers, designers and technicians from electric utilities and industrial firms wishing to gain a basic knowledge of the planning, commissioning, maintenance and operation of Siemens type SIPROTEC protective relays. These courses employ a combination of lecture, demonstration and hands-on exercises. Bench testing: IEC 61850 technology lab All protective relays installed in a Smart- Gear PDS switchgear lineup are programmed and bench tested in the Siemens IEC 61850 technology lab per specific test procedures before being shipped to the factory for installation in the switchgear and testing. The IEC 61850 technology lab is located at the Siemens facility in Wendell, North Carolina. The IEC 61850 technology lab is specifically designed for the purpose of developing, evaluating and testing advanced protective relay and monitoring, control and protection configurations. With Smart-Gear PDS, a customer factory acceptance test (FAT) of the protective relay system is optional as part of the project. Customer witness testing This service module is specifically designed to give customers the option to witness the testing process of the equipment prior to shipment from the Siemens factory in Querétaro, Mexico. All customers will be accompanied by a Siemens contract administrator or a project engineer throughout the witness testing process. This service is coordinated through the project manager. 27
Service and support modules Field services Support services are fully coordinated through our Wendell, North Carolina-based service organization. A toll-free customer service number and an after-hours emergency support number are established for prompt emergency help and response. These service lines provide access to resources that may be required to address the service needs or recommended operation and maintenance of the Smart-Gear PDS switchgear lineup. Smart-Gear PDS field services Installation and commissioning On-call maintenance agreements Technical field assistance. Smart-Gear PDS protection and control services Switchgear protective relay testing Generator system and protective relay testing. Spare parts A suggested spare parts list will be provided with the approval drawing package or several weeks after receipt of a purchase order for an Apps C (certified) project. 28
Instructions for specifying Smart-Gear PDS Instructions for specifying a Smart- Gear PDS switchgear lineup With Smart-Gear PDS, specifying medium-voltage, metal-clad switchgear is easy. All of the information preceeding this section has been designed to aid in completing the Smart-Gear PDS specification beginning on page 32. Layout of the Smart-Gear PDS specification form The following describes the layout of the Smart-Gear PDS specification form. The form consists of four main data entry blocks that are described in Figure 11: Layout of Smart-Gear PDS specification form. Instructions for completing the Smart- Gear PDS specification form The step-by-step instructions below are provided to help in completing the Smart- Gear PDS specification form. Each step refers to a block in Figure 11: Layout of Smart-Gear PDS specification form. Step A: Lineup information block 1. Complete the Smart-Gear PDS switchgear lineup information block for each switchgear lineup, except for the lineup bus that must be completed for each bus in each switchgear lineup. 2. For selecting the Smart-Gear PDS type, refer to Smart-Gear PDS types on page 6 to determine the type of Smart-Gear PDS needed. 3. To select the remote control application module, refer to Table 7: Remote control application modules on page 18 to review the options available and select the appropriate choice. 4. To select the special application module, refer to Table 8: Special application modules on page 19 to review the options available and select the appropriate choice. 5. To select a service module, refer to service and support modules on page 26 to review the options available and select the appropriate choice. 6. If desired, an electrically operated or manually operated Siemens ground and test device is available. Consult your local Siemens representative for more information. Step A: Smart-Gear PDS switchgear lineup information block Refer to Smart-Gear PDS types on page 6, remote control application modules on page 18, special application modules on page 19, communications and controls on page 23 and service and support modules on page 26. Figure 11: Layout of Smart-Gear PDS specification form Step B: Ratings and enclosures block Step C: Operation and functionality block Refer to system application modules on page 10. Step D: Sections and compartment requirements block Each page consists of one vertical sections and two cells are shown. Refer to, auxiliary application modules on page 13, circuit breaker application modules on page 14 and protection application modules on page 20. 29
Instructions for specifying Smart-Gear PDS Step B: Ratings and enclosure information block 1. Complete the information in the ratings and enclosure block for each switchgear lineup. Step C: Operation and functionality block 1. Complete the information in the operation and functionality block for the each switchgear lineup. 2. For an automatic transfer application module, refer to Table 2: Automatic transfer modules on page 10 to review the options available and select the appropriate choice. 3. For a protection application module, refer to Table 4: Protection application modules on page 12 to review the options available and select the appropriate choice. 4. Complete the control power data. 5. Complete the space heater entry as required. Step D: Sections and compartments requirements block for a circuit breaker, auxiliary or blank cell 1. Complete the information in the sections and compartment requirements block for all circuit breaker and auxiliary compartments. 2. Each block represents a cell (compartment) as the upper or lower portion of a vertical section. Cell A represents the upper cell and cell B represents the lower cell in a vertical section. 3. Complete the compartment type. Note: When selecting "equipped space," also select the applicable circuit breaker application module, which can be referenced in Table 6: Circuit breaker application modules on pages 15-17. 4. For an auxiliary application module, refer to Table 5: Auxiliary application modules on page 13 to review the options available and select the appropriate choice. 5. For the circuit breaker application module, refer to Table 6: Circuit breaker application modules on pages 15-17 to review the options available and select the appropriate choice. 6. For circuit breaker interlock application module, refer to Table 3: Circuit breaker interlock application modules on page 11 to review the options available and select the appropriate choice. 7. Note the location of the desired shipping splits. Do not locate shipping splits adjacent to bus-tie circuit breakers or between an auxiliary cell and a cell with a 3,000 A or 4,000 A circuit breaker compartment. Smart-Gear PDS specification form 1. Print the Smart-Gear PDS specification form starting on page 32 and then complete the required entries. 2. Refer to the directions provided in the instructions for specifying Smart-Gear PDS on pages 29 and 30. 3. Forward the completed form to your local Siemens representative for a proposal. Figure 12: Type GMSG-EO electrically operated ground and test device 30
Definitions and terminology Apps are software programs designed to be uploaded to the Smart-Gear PDS switchgear lineup network. Automatic transfer scheme is the system that enables automatic transfer of electrical power between one circuit breaker to another circuit breaker. Application modules are the building blocks for configuring a lineup of switchgear. Continuous function chart (CFC) programming is the diagrammatic language for the specification of mixed protective relays and other discrete continuous embedded systems. CFC permits the conversion of technological specifications into executable automation programs. Control wiring is the copper wiring between secondary control devices. DIGSI 4 is a Siemens tool for setting protective relays using MS Windows. DIGSI 4 is the logical innovation for easyto-use and user-friendly setting, commissioning and operating of all SIPROTEC protective relays, regardless of version. Digital circuitry is the communication interface between intelligent electronic devices (IEDs). Fiber-optic cable is flexible glass material used to transmit data. GOOSE is the abbreviation for generic object-oriented substation events and is the high-speed data transmission that bypasses normal communication. Hard-wired circuits are the copper wire interfaces among secondary devices. IEC 61850 is a global standard for substation automation communication protocol and is open Ethernet-based. Integrated controls is the combination of multiple functions into fewer devices. Interlocking, circuit breaker interconnects two or more circuit breakers with control circuits to open or close (or to prevent closing) depending on the application requirements. Interlocked, digital connects two or more circuit breakers via IEDs to open or close (or to prevent closing) depending on the application requirements. Interoperability is the ability of equipment to easily interface with other equipment supplied by different manufacturers. Programmable means equipment can be programmed to function. Restore, automatic is the automatic return to the preferred power source from the non-preferred source. Restore, manual is the manual return to the preferred power source from the nonpreferred source. Scalability is the ability of a system to handle additional hardware and functions with little impact on performance. Self-monitoring is the capability of the equipment to monitor its own functionality and advise (alert) the operator. Source, non-preferred is secondary or an alternate power source. Source, preferred is the primary or normal power source. Transition, closed is the closing of a circuit breaker prior to transferring of power, typically the tie circuit breaker in a main-tie-main breaker configuration. Transition, open is the opening of a circuit breaker prior to transferring of power, typically the tie circuit breaker in a maintie-main circuit breaker configuration. Usage-based maintenance is the advanced notification the equipment provides to the user of recommended maintenance based on time and/or operations. 31