Static Pressure High Limit

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1 Metasys Network Technical Manual 636 Air Handlers Section Technical Bulletin Issue Date 0590 Static Pressure High Limit Static pressure high limit File Name Path Name Main Function Accessories How It Works SPHLIM.CMP The following DOS path name indicates the location of the compound: <FMS>\APPS\HVAC\LOGIC\MISC\SPHLIM.CMP Proportional discharge static pressure high limit protection. You can use this compound only as an accessory to the STPR compound. The static pressure protection is performed in the Digital Control Module with no intervention required from other items on the network. The signal from the static pressure control compound (STPR) is restricted to be less than the signal for discharge static pressure high limit protection. The signal is then passed to the supply fan. As the discharge pressure approaches the setpoint, the signal is reduced to produce less static pressure. The setpoint of the SPHLIM (PIDL object) specifies the pressure at which the supply fan moves no air. This is defaulted to 4.0 in. W.C. ( Pa). The proportional band specifies the inches in water column (in. W.C.) below setpoint when the fan is allowed to supply full pressure. The default proportional band, 0.5 in. W.C. (125.0 Pa), will allow the supply fan to be at full capacity (100%) at 3.5 in. W.C. (875.0 Pa) [4.0 in. W.C. - (0.5 in. W.C.)] Johnson Controls, Inc. 1 Order No

2 Guidelines You can find important instructions and guidelines for using compounds in How to Use the Metasys GPL HVAC Library, located at the beginning of the App. Notes: GPL HVAC Library section. For information on the definition and the initial configuration of the objects and the function blocks, use GPL to examine this compound. You must define system and object names for all objects. You must define the hardware location for each object. You must define all the following AI, PIDL, and AOD objects as part of the same Digital Control Module (DCM): - The AI object connected to the DS-SP block - The SPHLIM (PIDL object) - The AOD object linked to the SFAN-AOO connection block. (The compound connected to the SFAN-AOD connection block may have additional requirements. Refer to the application note for that compound.) If a PIDL s object name is changed, make sure all references to that object name are also changed. To prevent overpressurization of the duct work, provide proper mechanical protection. I/O Requirements Table 1: I/O Requirements Input Requirements Name Of Block Note 1: Type Of Data Engineer Units Req? Range Default Description DS-SP Analog in. W.C. Yes - - Discharge static pressure SFAN-AOD Analog % Yes - - Supply fan command Output Requirements Name Of Connection Type Of Data Engineer Units Req? Range Low Limit Input Span Limits For Linked AOD Object: 1 High Limit Description SFAN-AOO Analog % Yes 0 to Supply fan AOD output IMPORTANT! Set the output span limits so that as the signal to the AOD object increases, the device connected to the AOD produces more pressure (moves more air). 2 Air Handlers Static Pressure High Limit

3 Port Requirements SPHLIM Object The template for the SPHLIM (PIDL object) includes screens (Figure 1 and Figure 2) for establishing the port definition requirements. PID LOOP OBJECT (PIDL) PORT DEFINITION Enter the system name of the AI object that is connected to the DS-SP block. INPUT REFERENCE DS-SP INPUT 4 INPUT 2 INPUT 5 INPUT 3 INPUT 6 F10 - SAVE, ESC/mouse click - CANCEL, PGUP/PGDN- PAGE Figure 1: PID Loop Object (PIDL) Port Definition PID LOOP OBJECT (PIDL) OUTPUT DEFINITION Enter the system name of the AODobject connected to SFAN-AOO.. OUTPUT 1 SFAN-AOO VALUE OUTPUT 5 OUTPUT 2 OUTPUT 6 OUTPUT 3 OUTPUT 7 OUTPUT 4 OUTPUT 8 F10 - SAVE, ESC/mouse click - CANCEL, PGUP/PGDN- PAGE Figure 2: PID Loop Object (PIDL) Output Definition Air Handlers Static Pressure High Limit 3

4 Port Requirements: SP-CTRL Object The SP-CTRL (PIDL object), found in the STPR compound, must be modified as shown below. PID LOOP OBJECT (PIDL) OUTPUT DEFINITION Enter the system name of the PIDL object SPHLIM. OUTPUT 1 SPHLIM SEL_INP OUTPUT 5 OUTPUT 2 OUTPUT 6 OUTPUT 3 OUTPUT 7 OUTPUT 4 OUTPUT 8 F10 - SAVE, ESC/mouse click - CANCEL, PGUP/PGDN- PAGE Figure 3: PID Loop Object (PIDL) Output Definition Process? No, this is a group compound. To view the compound s information, click once on the compound block. Example To see how this compound could be used with other objects and compounds, view file AHU3. The following DOS path name indicates the location of the file: <FMS>\APPS\AHU\AHU3.(GPL) 4 Air Handlers Static Pressure High Limit

5 Air Handlers Static Pressure High Limit 5

6 6 Air Handlers Static Pressure High Limit Notes

7 Notes Air Handlers Static Pressure High Limit 7

8 Notes Controls Group FAN E. Michigan Street Metasys Network Manual P.O. Box 423 Revision Date 0590 Milwaukee, WI Printed in U.S.A. 8 Air Handlers Static Pressure High Limit

Metasys and Companion

Metasys Network Technical Manual 636 App. Notes: Operator Devices Section Technical Bulletin Issue Date 0191 Metasys and Companion Application Page 3 Purpose of Application 3 Setting Up the Windows Terminal