General Specific MODBUS RTU protocol Rev. 15 REVISIONS

Transcription

1 Page 1 of 68 General Specific MODBUS RTU protocol Rev. 15 Written: U. T. ing. L. Guerrieri Verified: A. Q. ing. F. Adinolfi Approved: D. T. ing. E. Girardi Date: 22/03/2018 Status: Final REVISIONS REV. VER. DATE CHANGES WRITTEN VERIFIED APPROVED /07/98 Adding to pages 7 Goffredo Donati Cantobelli /12/98 Multivariable Read Canini Goffredo Cantobelli /02/00 Errata corrige Zoletto Donati Amato /05/00 New memory map function 06 Zoletto Donati Amato /11/00 Functions Zoletto Donati Amato /12/01 New command for SMART Più Bandini Adinolfi Amato /12/02 New ID for SMART96 Più; Voltage and Current ThdF for SMART Più and SMART96 Più. Different management of the requests with memory overflow (from V3.03) /11/03 New ID and Apparent energy measurement for SMART(96) Più V3.11(KVAh) /09/04 For SMART(96) Più from version V3.12. Update new instruments ID and new range for CT ratio 10 Bis 0 07/07/05 DUCA47(-72-SP) only for model Duca47-72-SP with serial interface and pulse outputs 10 Tris 0 18/01/07 Add note for DUCA47(-72-SP) answer for Function 17h Report slave ID Bandini Sangiorgi Adinolfi Amato Bandini Adinolfi Amato Sangiorgi Adinolfi Amato Bandini Adinolfi Amato Sangiorgi Adinolfi Amato

2 Page 2 of /05/11 Update for models DUCA-LCD96 i Sangiorgi Adinolfi Amato Update for output commands with active alarms Updated ID table for introduction of the DUCA /11/14 LCD models ii Update memory map for introduction of Guerrieri Adinolfi Amato harmonics and THD (DUCA-LCD models) Updated notes about binary formats used in map /09/17 Update for introduction of R5 / R8 iii commands and map Guerrieri Adinolfi Girardi /11/17 Update for introduction of R5/R8 floating point map Guerrieri Adinolfi Girardi /03/18 Errata Corrige Guerrieri Adinolfi Girardi Contents 1. COMMUNICATION FRAME IN RTU MODE (REMOTE TERMINAL UNIT) ACTIVATION OF MODBUS PROTOCOL AND AVAILABLE FUNCTIONS Function 01 : READ OUTPUT STATUS Function 03 : READ HOLDING REGISTERS Function 05 : FORCE SINGLE COIL Function 06 : PRESET SINGLE REGISTER Function 07 : READ EXCEPTION STATUS Function 17 : REPORT SLAVE ID EXCEPTIONS ON THE BUS CRC ALGORITHM i The models where a serial interface RS485 is available are: DUCA-LCD96 485, DUCA-LCD96 BASE-485, DUCA-LCD IO, DUCA-LCD RELE and, if not specified, will all be listed in the document with DUCA-LCD96. ii The models where a serial interface RS485 is available are: DUCA-LCD 485 e DUCA-LCD 485-ETH and, if not specified, will all be listed in the document with DUCA-LCD. iii The models where a serial interface RS485 is available are: R5 485, R5 485-RADIO, R8 485, R8 485-RADIO, R8 485-BT (11 relay outputs), R8 485-BT RADIO (11 relay outpus), R8 485-USB (11 relay outputs), R8 485-USB RADIO (11 relay outputs), and if not specified, will all be listed in the document with R5 or R8.

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4 Page 4 of Communication frame in RTU mode (Remote Terminal Unit) A MODBUS frame is composed of: T1 T2 T3 Address Function Data CRC T1 T2 T3 (8 bits) (8 bits) (N x 8 bits) (16 bits) in which: a) the Address field contains the address of the Slave to which the message is sent b) the Function field contains the code of the function that must be carried out by the Slave c) the Data field contains the information needed by the Slave to carry out a specific function or contains data collected from the Slave in response to a question d) the CRC field allows both the Master and the Slave to check a message in order to detect any errors in transmission. Sometimes, due to electrical noise or other interference, a message may be changed during the transmission from one unit to another. The error check ensures that neither the Master nor the Slave react to messages that have been haltered e) the T1 T2 T3 sequence represents the time that separates one frame from another, and corresponds to at least 3 and a half characters: during this period no one is allowed to talk on the bus, to let the instruments detect that a frame is over and another one is starting In RTU mode, the synchronisation of the frame can be maintained only by simulating a synchronous message. The receiving device, a Mach SMART for example, measures the time that separates the reception of one character and the reception of the subsequent one (for example, between address and function). If this time is longer than the time needed to transmit three and a half characters, then the message is considered lost and the next character arriving is considered to be an address, in other words the beginning of a new frame.

5 Page 5 of Activation of MODBUS protocol and available functions To activate the MODBUS protocol in the MACH SMART, Smarti Più and in DUCA47-72-SP, 1 must be selected in the last field of the Setup indicated by PROT (0 = DUCBUS, 1 = MODBUS). For R8, DUCA-LCD96 and DUCA-LCD models is necessary enter the setup menu and set Prot MODBUS in the Protocol page of the Communication s menu. For R5 it is necessary enter the setup and set Prt = Mod The available MODBUS functions are reported in the following table: MODBUS Functions Action performed in the analyser 01 = READ OUTPUT STATUS Read data relative to the output status 03 = READ HOLDING REGISTERS Reads data relative to the Measurements and the Setup 05 = FORCE SINGLE COIL Set the output state 06 = PRESET SINGLE REGISTER Sets Setup parameters 07 = READ EXCEPTION STATUS Reads Instrument status 17 = REPORT SLAVE ID Reads the identification of the instrument type IMPORTANT NOTE REGARDING FUNCTIONS 3 AND 6 DESCRIBED BELOW: Whenever the user employs commercial programs for reading the data from the Slaves, and these programs are already designed for handling the MODBUS protocol, it is necessary to use the addresses of the storage locations indicated in the first left-hand column of the tables relative to functions 3 and 6 illustrated below. Instead, whenever the user writes his own program to read the data it is necessary to decrease by one the addresses reported. For example: the Master wishes to read from Mach SMART with address 3 the value of the three-phase equivalent current, available at memory address 18 (= 12Hex). The communication frame of the Master to the Slave, with hexadecimal values, will be the following: EC where: 03 = address of Mach SMART (Slave) no. 03

6 Page 6 of = function requested by the Master, in this case measure reading request = address, reduced by one unit (12H - 1H = 11H), of the storage location to be read and containing the value of the three-phase equivalent current = number of registers to be read beginning with address 11H 95 EC = CRC The Slave response frame to the Master in hexadecimal values will be the following: E0 D9 EB in which: 03 = address of Mach SMART (Slave) no = function requested by the Master, in this case measure reading request 04 = number of data bytes following in the frame E0 = hex value of the three-phase equivalent current (01E0H = 480 hundredths of A = 4.8A) D9 EB = CRC 2.1 Function 01 : READ OUTPUT STATUS This function is used to read the status of the SMART96, SMART Più, DUCA-LCD or DUCA- LCD96 output; the output is treated like a coil, following MODBUS standard. The request and answer frame are described below: Read request (master): Addr Func Coil Addr Coil Addr Number of Number of CRC CRC Start H Start L Coils H Coils L 1Fh 01h 00h 00h 00h 08h 3Eh 72h

7 Page 7 of 68 In the example above the read output function Func = 01 is sent to the slave with address Addr = 1Fh, starting from register Coil Addr Start = 0000h (compulsory) for Number of coils = 08h (compulsory) adjacent coils. The frame is closed with CRC=3E72h. Reply (slave): Addr Func Byte Data Coil CRC CRC Count Byte 0H 1Fh 01h 01h 00h 57h A0h The answer fields, as described above, are the slave address Addr = 1Fh, the function executed Func = 01, the number of data bytes following Byte Count = 01h, the coil value 00h. In the SMART 96 the 5 th bit is its only output, all the others are forced to 0; for the SMART Più the relevant bits are bit 0 and bit 1 (1 st and 2 nd bit respectively for output 1 and output 2); for models DUCA-LCD and DUCA-LCD96 are bit 0 and bit 1 (1 st and 2 nd bit respectively for output 1 and output 2); furthermore, only for model DUCA-LCD RELE, bit 2 and bit 3 are related respectively to output 3 and output 4. The frames ends with the CRC. This function is available in the SMART 96 from version 1.01 onwards and for model 2P of SMART Più. For DUCA47(-72)-SP the command is not operational. This function is also used to read the status of the R5 or R8 output; the output is treated like a coil, following MODBUS standard. The request and answer frame are described below: Read request (master): Addr Func Coil Addr Coil Addr Number of Number of CRC CRC Start H Start L Coils H Coils L 1Fh 01h 00h 00h 00h 10h 3Eh 78h In the example above the read output function Func = 01 is sent to the slave with address Addr = 1Fh, starting from register Coil Addr Start = 0000h (compulsory) for Number of coils = 10h (compulsory) adjacent coils. The frame is closed with CRC=3E78h. Reply (slave): Addr Func Byte Data Coil Data Coil CRC CRC Count Byte 1H Byte 0H 1Fh 01h 02h 00h 00h 11h FEh

8 Page 8 of 68 The answer fields, as described above, are the slave address Addr = 1Fh, the function executed Func = 01, the number of data bytes following Byte Count = 02h, the coil value 0000h. For R5, bit 0, bit 1, bit 2, bit 3 and bit 4 are respectively associated with relay output 1, relay output 2, relay output 3, relay output 4 and relay output 5. For R8, bit 0, bit 1, bit 2, bit 3, bit 4, bit 5, bit 6, bit 7, bit 9 and bit 10 are respectively associated with relay output 1, relay output 2, relay output 3, relay output 4, relay output 5, relay output 6, relay output 7, relay output 8, relay output 9, relay output 10 and relay output Function 03 : READ HOLDING REGISTERS This function reads one or more memory adjacent locations, each one being 1 or 2-word sized. It is possible to read up to 12 or 24 iv consecutive measures *. Moreover SMART Più can read a Mix of measures previously configured (see 2.4). Below are described the read request format (from master to slave) and the reply format (from slave to master). Read request (master): Addr Func Data Start Data Start Data # of Data # CRC CRC Register H Register L Regs H Regs L 1Fh 03h 00h 11h 00h 08h 17h B7h In the example above, the master sends the read function Func = 03 to the slave with address Addr = 1Fh, starting from base register address Data Start Register = 0011h for Data Regs = 08h consecutive registers. So the command reads all registers from address 0011h to 0018h. The CRC = 17B7h closes the data stream. (Note: the physical address is always obtained from measure address reduced of 1 unit, see note above). Reply (slave): Addr Func Byte Data Out Reg Data Out Reg Data Out Data Out CRC CRC count 0012 H 0012 L Reg 0018H Reg 0018L 1Fh 03h 10h 10h EFh.. 3Bh 40h xxh yyh iv SMART Più family, DUCA47(-72)-SP, DUCA-LCD, DUCA-LCD96, R5 and R8 family: 24 measures. * Mach SMART with firmware versions earlier than 1.H07 allow only one value (2 words) per enquiry to be read.

9 Page 9 of 68 The table above shows the fields in the MACH SMART reply, which are : -Addressed Slave Addr = 1Fh -Function code request Func = 03 -Number of data byte following Byte Count = 10h -Data byte fields requested by the master -CRC closes the reply data stream There are three particular cases that can happen using this command; the first is related to the quantity of requested memory, the second is related to the beginning of the requested segment and the last is related to the quantity of the requested words. In particular, if the quantity of the requested bytes is greater than the MACH s memory extension, the instrument will answer an INVALID DATA for the not available values; for example, if are requested 20 bytes from the last fourth valid address, a part of the request overflows in the not available memory. The exceeded bytes will be filled by the SMART with the value FFh v, indicating a not managed value for those memory cells. The second particular case is related to a request starting from a not valid address, when the request starts from an address not present in the following table. In this case the instrument will answer with an exception 02 ILLEGAL DATA ADDRESS (see chapter 3). The last particular case is the request of a number of word greater than the maximum for the instrument: in this case the instrument will answer with an exception 02 ILLEGAL DATA address (see chapter 3). Memory map The following table indicates the correspondence between the address of the location, the number of accessible words beginning with that address, the description of the measurement value, the unit of measurement of the measurement value and the binary format. Formats of the variables passed: - Unsigned Long: means a binary number of 2 words (32 bits) unsigned - Bit Signed Long: means a binary number of 2 words (32 bits) if not, the MSB is set to 1. For example: h = Signed Int: means a binary 2 s-complement number - : is a binary number of 1-word (16-bit) unsigned v SMARTPiù from V on; in the V the slave answer at this request was an exception 02.

10 Page 10 of 68 Add. Word Measurement description Unit Format Frequency Tenths of Hz Unsigned Long Three-phase Equivalent Voltage V Unsigned Long Linked Voltage (line 1 - line 2) vi V Unsigned Long Linked Voltage (line 2 - line 3) vi V Unsigned Long Linked Voltage (line 3 - line 1) vi V Unsigned Long Voltage between Phase and Neutral line 1 vi V Unsigned Long Voltage between Phase and Neutral line 2 vi V Unsigned Long Voltage between Phase and Neutral line 3 vi V Unsigned Long Three-phase Equivalent Current Hundredths of A Unsigned Long Current Line 1 vi Hundredths of A Unsigned Long Current Line 2 vi Hundredths of A Unsigned Long Current Line 3 vi Hundredths of A Unsigned Long Three-phase equivalent power factor * Hundredths bit-signed / Unsigned Long vii Power factor line 1 * vi Hundredths bit-signed Long Power factor line 2 * vi Hundredths bit-signed Long Power factor line 3 * vi Hundredths bit-signed Long Three-phase equivalent active power W bit-signed Long viii Average three-phase equivalent active power W bit-signed Long viii Maximum three-phase equivalent active W bit-signed Long viii power Active power line 1 vi W bit-signed Long viii Active power line 2 vi W bit-signed Long viii Active power line 3 vi W bit-signed Long viii Average active power line 1 vi W bit-signed Long viii Average active power line 2 vi W bit-signed Long viii vi Not available for R5 and R8 Models vii For SMART Più, DUCA47(-72)-SP, DUCA-LCD and DUCA-LCD96 this value is a bit-signed Long. viii For models DUCA-LCD and DUCA-LCD96 the values of Active Power could be negatives in Cogeneration.

11 Page 11 of Average active power line 3 vi W bit-signed Long viii Maximum active power line 1 vi W bit-signed Long viii Maximum active power line 2 vi W bit-signed Long viii Maximum active power line 3 vi W bit-signed Long viii Three-phase equivalent apparent power VA bit-signed Long Average three-phase equivalent apparent VA Unsigned Long power Maximum three-phase equivalent apparent VA Unsigned Long power Apparent power line 1 vi VA Unsigned Long Apparent power line 2 vi VA Unsigned Long Apparent power line 3 vi VA Unsigned Long Average apparent power line 1 vi VA Unsigned Long Average apparent power line 2 vi VA Unsigned Long Average apparent power line 3 vi VA Unsigned Long Maximum apparent power line 1 vi VA Unsigned Long Maximum apparent power line 2 vi VA Unsigned Long Maximum apparent power line 3 vi VA Unsigned Long Three-phase equivalent reactive power VAr bit-signed Long ix Average three-phase equivalent reactive VAr bit-signed Long ix power Maximum three-phase equivalent reactive VAr bit-signed Long ix power Reactive power line 1 vi VAr bit-signed Long ix Reactive power line 2 vi VAr bit-signed Long ix Reactive power line 3 vi VAr bit-signed Long ix Average reactive power line 1 vi VAr bit-signed Long ix Average reactive power line 2 vi VAr bit-signed Long ix Average reactive power line 3 vi VAr bit-signed Long ix Maximum reactive power line 1 vi VAr bit-signed Long ix Maximum reactive power line 2 vi VAr bit-signed Long ix ix For models DUCA-LCD and DUCA-LCD96 the values of Reactive Power could be negative (positive if inductive, negative if capacitive).

12 Page 12 of Maximum reactive power line 3 vi VAr bit-signed Long ix Three-phase equivalent active energy Tens of Wh Unsigned Long Active energy line 1 vi Tens of Wh Unsigned Long Active energy line 2 vi Tens of Wh Unsigned Long Active energy line 3 vi Tens of Wh Unsigned Long Three-phase equivalent reactive/apparent Tens of Unsigned Long energy x VArh/VAh Reactive/Apparent energy line 1 x vi Tens of Unsigned Long VArh/VAh Reactive/Apparent energy line 2 x vi Tens of Unsigned Long VArh/VAh Reactive/Apparent energy line 3 x vi Tens of Unsigned Long VArh/VAh Max. average three-phase active power W bit-signed Long viii Line 1 normal format voltage ThdF (only for DUCA-LCD96 and DUCA-LCD; for SMART Più and SMART96 Più from revision V. 3.10) & vi Line 2 normal format voltage ThdF (only for DUCA-LCD96 and DUCA-LCD & vi Line 3 normal format voltage ThdF (only for DUCA-LCD96 and DUCA-LCD) & vi Line 1 normal format current ThdF (only for DUCA-LCD96 and DUCA-LCD; for SMART Più and SMART96 Più from revision V. 3.10) & vi Line 2 normal format current ThdF (only for DUCA-LCD96 and DUCA-LCD)& vi Line 3 normal format current ThdF (only for DUCA-LCD96 and DUCA-LCD) & vi Maximum Average Active Power line 1 (only for DUCA-LCD96 and DUCA-LCD) vi Hundredths Hundredths Hundredths Hundredths Hundredths Hundredths W Unsigned Long Unsigned Long Unsigned Long Unsigned Long Unsigned Long Unsigned Long bit-signed Long x The DUCA-LCD96, DUCA-LCD and DUCA47(-72)-SP return always the Reactive Energy; the SMART Più and the SMART96 Più, version 3.11 or later, return the Apparent Energy when the CFG parameter is set to 28, 33 or 38, otherwise the Reactive Energy. Not valid for other instruments.

13 Page 13 of Maximum Average Active Power line 2 (only for DUCA-LCD96 and DUCA-LCD) vi Maximum Average Active Power line 3 (only for DUCA-LCD96 and DUCA-LCD) vi Max. average three-phase Apparent Power (only for DUCA-LCD96 and DUCA-LCD) Maximum Average Apparent Power line 1 (only for DUCA-LCD96 and DUCA-LCD) vi Maximum Average Apparent Power line 2 (only for DUCA-LCD96 and DUCA-LCD) vi Maximum Average Apparent Power line 3 (only for DUCA-LCD96 and DUCA-LCD) vi W W VA VA VA VA bit-signed Long bit-signed Long Unsigned Long Unsigned Long Unsigned Long Unsigned Long KV constant $ (VT transformation ratio) Unit Unsigned Long KA constant $ (CT transformation ratio) Unit Unsigned Long Time of Average Minute Unsigned Long Average Active Power from pulses input W Unsigned Long (CH1) only for DUCA-LCD and DUCA- LCD IO Average Reactive Power from pulses input VAr Unsigned Long (CH2) only for DUCA-LCD and DUCA- LCD IO Active Energy from pulses input (CH1) Tens of Wh Unsigned Long only for DUCA-LCD and DUCA-LCD IO Reactive Energy from pulses input (CH2) Tens of VArh Unsigned Long only for DUCA-LCD and DUCA-LCD IO Current threshold for timer 2 activation (only Hundredths of A Unsigned Long for DUCA-LCD and DUCA-LCD96). Note: the read value does not include the value of KA Three-phase equivalent Apparent Energy Tens of VAh Unsigned Long

14 Page 14 of 68 (only for DUCA-LCD and DUCA-LCD96) Apparent Energy line 1 (only for DUCA- Tens of VAh Unsigned Long LCD and DUCA-LCD96) Apparent Energy line 2 (only for DUCA- Tens of VAh Unsigned Long LCD and DUCA-LCD96) Apparent Energy line 3 (only for DUCA- Tens of VAh Unsigned Long LCD96) Generated Three-phase equivalent Active Tens of Wh Unsigned Long Energy (only for DUCA-LCD and DUCA- LCD96) Generated Active Energy line 1 (only for Tens of Wh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Active Energy line 2 (only for Tens of Wh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Active Energy line 3 (only for Tens of Wh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Three-phase equivalent Reactive Tens of VArh Unsigned Long Energy (only for DUCA-LCD and DUCA- LCD96) Generated Reactive Energy line 1 (only for Tens of VArh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Reactive Energy line 2 (only for Tens of VArh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Reactive Energy line 3 (only for Tens of VArh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Three-phase equivalent Apparent Tens of VAh Unsigned Long Energy (only for DUCA-LCD and DUCA- LCD96) Generated Apparent Energy line 1 (only for Tens of VAh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Apparent Energy line 2 (only for Tens of VAh Unsigned Long DUCA-LCD and DUCA-LCD96) Generated Apparent Energy line 3 (only for Tens of VAh Unsigned Long DUCA-LCD and DUCA-LCD96) Not used st measure configured for the Mix + vi Depend Long nd measure configured for the Mix + vi Depend Long rd measure configured for the Mix + vi Depend Long

15 Page 15 of th measure configured for the Mix + vi Depend Long th measure configured for the Mix + vi Depend Long th measure configured for the Mix + vi Depend Long Total Harmonic Distortion (THDI1) current line 1 (only for Duca-LCD and R5/R8) Total Harmonic Distortion (THDI2) current line 2 (only for Duca-LCD) Total Harmonic Distortion (THDI3) current line 3 (only for Duca-LCD) Total Harmonic Distortion (THDV1) voltage line 1 (only for Duca-LCD and R5/R8) Total Harmonic Distortion (THDV2) voltage line 2 (only for Duca-LCD) Total Harmonic Distortion (THDV3) voltage line 3 (only for Duca-LCD) (thousandths of (thousandths of (thousandths of (thousandths of (thousandths of (thousandths of Unsigned Long Unsigned Long Unsigned Long Unsigned Long Unsigned Long Unsigned Long Max frequency xi Tens of Hz Unsigned Long Min frequency xi Tens of Hz Unsigned Long Maximum Three-phase Equivalent Current xi Hundredths of A Unsigned Long Minimum Three-phase Equivalent Current xi Hundredths of A Unsigned Long Average Three-phase Equivalent Current xi Hundredths of A Unsigned Long Maximum Average Three-phase Equivalent Hundredths of A Unsigned Long Current xi Not used Maximum Three-phase Equivalent Voltage xi Volt Unsigned Long Minimum Three-phase Equivalent Voltage xi Volt Unsigned Long Not used Minimum Three-phase Equivalent Voltage VA Unsigned Long Apparent Power xi 0294 Not used - - xi Only for R5 and R8 Models

16 Page 16 of Minimum Three-phase Equivalent Voltage Watt bit-signed Long Active Power xi 0302 Not used Minimum Three-phase Equivalent Voltage VAr bit-signed Long Reactive Power xi Maximum Three-phase Equivalent Voltage VAr bit-signed Long Reactive Power xi Not used Maximum Three-phase Equivalent Power Hundredths bit-signed Long Factor xi Minimum Three-phase Equivalent Power Factor xi Hundredths bit-signed Long Average Three-phase Equivalent Power Hundredths bit-signed Long Factor xi Daily Average Three-phase Equivalent Hundredths bit-signed Long Power Factor xi Weekly Average Three-phase Equivalent Hundredths bit-signed Long Power Factor xi Monthly Average Three-phase Equivalent Hundredths bit-signed Long Power Factor xi Not used Three-phase Equivalent Cosfi xi Hundredths bit-signed Long Maximum Three-phase Equivalent Cosfi xi Hundredths bit-signed Long Minimum Three-phase Equivalent Cosfi xi Hundredths bit-signed Long Average Three-phase Equivalent Cosfi xi Hundredths bit-signed Long Daily Average Three-phase Equivalent Cosfi xi Weekly Average Three-phase Equivalent Cosfi xi Monthly Average Three-phase Equivalent Cosfi xi Hundredths Hundredths Hundredths bit-signed Long bit-signed Long bit-signed Long

17 Page 17 of Not used Delta-KVAr VAr bit-signed Long Total Harmonic Distortion (THDI1) current Unsigned Long line 1 xi Total Harmonic Distortion (THDV1) voltage Unsigned Long line 1 xi Temperature xi Tens of C bit-signed Long Maximum temperature xi Tens of C bit-signed Long Minimum temperature xi Tens of C bit-signed Long Maximum Total Harmonic Distortion Unsigned Long (THDI1) current Maximum Total Harmonic Distortion Unsigned Long (THDV1) voltage 0408 Not used Number of insertion C1 xi Unit Unsigned Long Number of insertion C2 xi Unit Unsigned Long Number of insertion C3 xi Unit Unsigned Long Number of insertion C4 xi Unit Unsigned Long Number of insertion C5 xi Unit Unsigned Long Number of insertion C6 xii Unit Unsigned Long Number of insertion C7 xii Unit Unsigned Long Number of insertion C8 xii Unit Unsigned Long Number of insertion C9 xii Unit Unsigned Long Number of insertion C10 xii Unit Unsigned Long Number of insertion C11 xii Unit Unsigned Long 0432 Not used Contact operation C1 xi Unit Unsigned Long Contact operation C2 xi Unit Unsigned Long Contact operation C3 xi Unit Unsigned Long Contact operation C4 xi Unit Unsigned Long Contact operation C5 xi Unit Unsigned Long Contact operation C6 xii Unit Unsigned Long xii Only for R8 Models

18 Page 18 of Contact operation C7 xii Unit Unsigned Long Contact operation C8 xii Unit Unsigned Long Contact operation C9 xii Unit Unsigned Long Contact operation C10 xii Unit Unsigned Long Contact operation C11 xii Unit Unsigned Long 0492 Not used Real power step C1 xi VAr Unsigned Long Real power step C2 xi VAr Unsigned Long Real power step C3 xi VAr Unsigned Long Real power step C4 xi VAr Unsigned Long Real power step C5 xi VAr Unsigned Long Real power step C6 xii VAr Unsigned Long Real power step C7 xii VAr Unsigned Long Real power step C8 xii VAr Unsigned Long Real power step C9 xii VAr Unsigned Long Real power step C10 xii VAr Unsigned Long Real power step C11 xii VAr Unsigned Long 0552 Not used Working time C1 xi hours Unsigned Long Working time C2 xi hours Unsigned Long Working time C3 xi hours Unsigned Long Working time C4 xi hours Unsigned Long Working time C5 xi hours Unsigned Long Working time C6 xii hours Unsigned Long Working time C7 xii hours Unsigned Long Working time C8 xii hours Unsigned Long Working time C9 xii hours Unsigned Long Working time C10 xii hours Unsigned Long Working time C11 xii hours Unsigned Long 0612 Not used High voltage alarm number xi Unit Unsigned Long

19 Page 19 of High current alarm number xi Unit Unsigned Long Low voltage alarm number xi Unit Unsigned Long Low current alarm number xi Unit Unsigned Long THDI% alarm number xi Unit Unsigned Long THDV% alarm number xi Unit Unsigned Long Temperature alarm number xi Unit Unsigned Long High cosfi alarm number xi Unit Unsigned Long Low cosfi alarm number xi Unit Unsigned Long Voltage dip alarm number xi Unit Unsigned Long mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend mix list value xi Depend Depend Number of fan alarm xii Unit Unsigned Long Minimum Total Harmonic Distortion Unsigned Long (THDI1) current line Minimum Total Harmonic Distortion Unsigned Long

20 Page 20 of (THDV1) voltage line Not used Maximum Delta-KVAr VAr bit-signed Long Minimum Delta-KVAr VAr bit-signed Long Average Delta-KVAr VAr bit-signed Long Maximum Average Delta-KVAr VAr bit-signed Long Daily Average Delta-KVAr VAr bit-signed Long Weekly Average Delta-KVAr VAr bit-signed Long Monthly Delta-KVAr VAr bit-signed Long Alarms Status xi(a) Unit Unsigned Long Battery Breakage Status xi (b) Unit Unsigned Long Maximum Battery Insertion Status xi ( c ) Unit Unsigned Long Not used Harmonic module H0 current line 1 (only for Duca-LCD) β (thousandths of Harmonic Module H1 current line 1 (only for Duca-LCD) β (thousandths of Harmonic Module Hn current line 1 (only for Duca-LCD and R8) β (thousandths of Harmonic module H31 current line 1 (only for Duca-LCD and R8) β (thousandths of Harmonic module Hn current line 1 (only for R8) β (thousandths of Harmonic module H60 current line 1 (only for R8) β (thousandths of Not used Harmonic module H0 voltage line 1 (only for Duca-LCD) β (thousandths of

21 Page 21 of Harmonic Module H1 voltage line 1 (only for Duca-LCD) β (thousandths of Harmonic Module Hn voltage line 1 (only for Duca-LCD and R8) β (thousandths of Harmonic module H31 voltage line 1 (only for Duca-LCD and R8) β (thousandths of H Harmonic Module Hn voltage line 1 (only for R8) β (thousandths of Harmonic module H60 voltage line 1 (only for R8) β (thousandths of 1 Not used Harmonic module H0 current line 2 (only for Duca-LCD) β (thousandths of Harmonic Module H1 current line 2 (only for Duca-LCD) β (thousandths of Harmonic Module Hn current line 2 (only for Duca-LCD) β (thousandths of Harmonic module H31 current line 2 (only for Duca-LCD) β (thousandths of Not used Harmonic module H0 voltage line 2 (only for Duca-LCD) β (thousandths of Harmonic Module H1 voltage line 2 (only for Duca-LCD) β (thousandths of Harmonic Module Hn voltage line 2 (only for Duca-LCD) β (thousandths of Harmonic module H31 voltage line 2 (only for Duca-LCD) β (thousandths of

22 Page 22 of Not used Harmonic module H0 current line 3 (only for Duca-LCD) β (thousandths of Harmonic Module H1 current line 3 (only for Duca-LCD) β (thousandths of Harmonic Module Hn current line 3 (only for Duca-LCD) β (thousandths of Harmonic module H31 current line 3 (only for Duca-LCD) β (thousandths of Not used (thousandths of Harmonic module H0 voltage line 3 (only for Duca-LCD) β (thousandths of Harmonic Module H1 voltage line 3 (only for Duca-LCD) β (thousandths of Harmonic Module Hn voltage line 3 (only for Duca-LCD) β (thousandths of Harmonic module H31 voltage line 3 (only for Duca-LCD) β (thousandths of Not used CT primary xi A Unsigned Long CT secondary xi A Unsigned Long CT phase insertion xi Unit Unsigned Long Enable CT inversion xi Unit Unsigned Long Enable cogeneration xi Unit Unsigned Long Frequency mode xi Unit Unsigned Long VT primary xi Volt Unsigned Long VT secondary xi Volt Unsigned Long

23 Page 23 of Voltage phase xi Unit Unsigned Long Step voltage xi Volt Unsigned Long Enable manual mode xi Unit Unsigned Long Target cosfi xi thousandths bit-signed Long Cosfi tolerance xi thousandths Unsigned Long Capacitor discharge time xi Sec Unsigned Long Connection time: connection/disconnection Sec Unsigned Long time between consecutive switching xi Relay Output 1 function xi Unit Unsigned Long Step C1 power xi VAr Unsigned Long Alarm type for output 1 xi Unit Unsigned Long Relay Output 2 function xi Unit Unsigned Long Step C2 power xi VAr Unsigned Long Alarm type for output 2 xi Unit Unsigned Long Relay Output 3 function xi Unit Unsigned Long Step C3 power xi VAr Unsigned Long Alarm type for output 3 xi Unit Unsigned Long Relay Output 3 function xi Unit Unsigned Long Step C4 power xi VAr Unsigned Long Alarm type for output 4 xi Unit Unsigned Long Relay Output 5 function xi Unit Unsigned Long Step C5 power xi VAr Unsigned Long Alarm type for output 5 xi Unit Unsigned Long Relay Output 6 function xii Unit Unsigned Long Step C6 power xii VAr Unsigned Long Alarm type for output 6 xii Unit Unsigned Long Relay Output 7 function xii Unit Unsigned Long Step C7 power xii VAr Unsigned Long Alarm type for output 7 xii Unit Unsigned Long Relay Output 8 function xii Unit Unsigned Long Step C8 power xii VAr Unsigned Long Alarm type for output 8 xii Unit Unsigned Long Relay Output 9 function xii Unit Unsigned Long Step C9 power xii VAr Unsigned Long Alarm type for output 9 xii Unit Unsigned Long Relay Output 10 function xii Unit Unsigned Long Step C10 power xii VAr Unsigned Long

24 Page 24 of Alarm type for output 10 xii Unit Unsigned Long Relay Output 11 function xii Unit Unsigned Long Step C11 power xii VAr Unsigned Long Alarm type for output 11 xii Unit Unsigned Long Integration time for average values xi Min Unsigned Long Communication protocol xi Unit Unsigned Long Serial communication address xi Unit Unsigned Long Serial communication baudrate xi Unit Unsigned Long High voltage alarm threshold xi % of VT Unsigned Long primary High voltage alarm delay xi sec Unsigned Long High current alarm threshold xi % of CT primary Unsigned Long High current alarm delay xi sec Unsigned Long Low voltage alarm threshold xi % of VT Unsigned Long primary Low voltage alarm delay xi sec Unsigned Long Low current alarm threshold xi (% of CT Unsigned Long primary) x Low current alarm delay xi sec Unsigned Long THDV% alarm threshold xi % Unsigned Long THDV% alarm delay xi sec Unsigned Long THDI% alarm threshold xi % Unsigned Long THDI% alarm delay xi sec Unsigned Long Temperature alarm threshold xi C Unsigned Long Temperature alarm delay xi sec Unsigned Long Enable disconnection time xi Unit Unsigned Long Disconnection time xi Unit Unsigned Long PFC algorithm evaluation time xi Unit Unsigned Long Transient exhaustion time for disinsertion xi Unit Unsigned Long Transient exhaustion time for insertion xi Unit Unsigned Long Enable stability control for sliding win. avg. Unit Unsigned Long xi Percentage deviation for sliding win. avg. xi Unit Unsigned Long Inductors presence xi Unit Unsigned Long Degradation threshold 1 (without inductors) Unit Unsigned Long xi Breakage threshold 1(without inductors) xi Unit Unsigned Long Degradation threshold 2 (with inductors) xi Unit Unsigned Long

25 Page 25 of Breakage threshold 2 (with inductors) xi Unit Unsigned Long Enable alarm reset xi Unit Unsigned Long Enable harmonic analisys xi Unit Unsigned Long Autodiagnostic threshold xi Unit Unsigned Long MHz address xi Unit Unsigned Long MHz channel xi Unit Unsigned Long MHz power xi Unit Unsigned Long Network type xi Unit Unsigned Long Instrument ID xi Unit Unsigned Long Serial number: week xi Unit Unsigned Long Serial number: year xi Unit Unsigned Long Serial number: sequential number xi Unit Unsigned Long FW version: major xi Unit Unsigned Long FW version: sub xi Unit Unsigned Long Bootloader version: major xi Unit Unsigned Long Bootloader version: sub xi Unit Unsigned Long Log period xii sec Unsigned Long Fisrt measure log xii Unit Unsigned Long Second measure log xii Unit Unsigned Long Voltage dip duration xi msec Unsigned Long Manual status C1 xi Unit Unsigned Long Manual status C2 xi Unit Unsigned Long Manual status C3 xi Unit Unsigned Long Manual status C4 xi Unit Unsigned Long Manual status C5 xi Unit Unsigned Long Manual status C6 xii Unit Unsigned Long Manual status C7 xii Unit Unsigned Long Manual status C8 xii Unit Unsigned Long Manual status C9 xii Unit Unsigned Long Manual status C10 xii Unit Unsigned Long Manual status C11 xii Unit Unsigned Long 2330 Not used Phase offset xii Unsigned Long Setpoint cosfi 2 xii thousandths Unsigned Long Setpoint cosfi 3 xii thousandths Unsigned Long

26 Page 26 of Setpoint cosfi 4 xii thousandths Unsigned Long Band B1 xii Unit Unsigned Long Band B2 xii Unit Unsigned Long Band B3 xii Unit Unsigned Long Band B4 xii Unit Unsigned Long Step disconnection xii Unit Unsigned Long 2408 Not used Not used Not used Not used Not used Not used Fan control threshold xii C Unsigned Long Fan control delay xii sec Unsigned Long High cosfi alarm delay xi min Unsigned Long Low cosfi alarm delay xi min Unsigned Long Language xii Unit Unsigned Long Temperature measurement unit xii Unit Unsigned Long 2432 Not used Not used Backlight level xii Unit Unsigned Long Automatic backlight turn-off xii Unit Unsigned Long LCD display contrast xii Unit Unsigned Long Summertime xii Unit Unsigned Long Imax harmonic xi ma Unsigned Long Alarm mask xi Unit Unsigned Long Language version: major xi Unit Unsigned Long Language version: sub xi Unit Unsigned Long Max connection time xi hours Unsigned Long (*) Regarding the power factor, please note that: power factor of the three lines may be negative; the instruments report negative numbers with the most significant bit (the 32 nd ) high (1) in case of negative Power Factor (capacitive), while positive numbers have the same bit low (0) in case of positive Power Factor (inductive).

27 Page 27 of 68 when the power factor for a line is undefined (current is zero), the instruments return the value 2 (200 cents) to report about this situation (+) For the Mix of measure pay attention to the follows: it is available only for SMART Più / SMART96 Più release V or later. This feature is not present in the other instruments (for R5 / R8 refer to addresses ) if not set or after a global reset, the measures are set to the first 6 measures of the list (frequency, three-phase equivalent voltage...) (&) For the voltage and current ThdF pay attention to the followings: the ThdF represents the normalised voltage and current crest factor it is available only for SMART Più and SMART 96 Più from revision V and for DUCA-LCD96 if the instruments SMART Più or SMART96 Più are configured with PAR function, they respond to the measure s request in the same way as the measure didn t exist the memories 126, 128 and 132, 134 are reserved for line 2 and line 3 ThdF and are significant only for the model DUCA-LCD96, since the SMART Più and SMART 96 Più measure the ThdF only from the line 1 even if the instrument is set to display the ThdF % (percentage format), when the memory values corresponding to the addresses from 124 to 134 are requested, it answers always with the corresponding ThdF in normal format in case the ThdF isn t computable (e.g. when current = 0), the instrument provides two words equal to FFFFh, corresponding to an INVALID DATA ($) For R5, R8, DUCA-LCD and DUCA-LCD96 the reading of KA or KV returns the ratio, set in the instrument, between the current (voltage) of primary and the current (voltage) of secondary. For example, if in the setup menu was set for the CT ratio the value 100/5, then the MODBUS command returns 20. (a) Reading the Alarms status, please note that: the value is to convert in bit-field (1 = ON and 0 = OFF) and the meaning of the bit are shown in the table below. For R8: Bit0 Bit1 Bit2 High voltage alarm status High current alarm status Low voltage alarm status

28 Page 28 of 68 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 Low current alarm status THDI% alarm status THDV% alarm status Temperature alarm status Fan alarm status High cosfi alarm status Low cosfi alarm status Voltage dip alarm status For R5: Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 High voltage alarm status High current alarm status Low voltage alarm status Low current alarm status THDI% alarm status THDV% alarm status Temperature alarm status High cosfi alarm status Low cosfi alarm status Voltage dip alarm status (b) Reading the battery breakage status, please note that: the value is to convert in bit-field (1 = BROKEN and 0 = OK) and the meaning of the bit are shown in the table below. For R5: Bit0 Bit1 Bit2 Bit3 Bit4 C1 step breakage status C2 step breakage status C3 step breakage status C4 step breakage status C5 step breakage status For R8: Bit0 C1 step breakage status

29 Page 29 of 68 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 C2 step breakage status C3 step breakage status C4 step breakage status C5 step breakage status C6 step breakage status C7 step breakage status C8 step breakage status C9 step breakage status C10 step breakage status C11 step breakage status (c) Reading the maximum battery insertion status, please note that: the value is to convert in bit-field (1 = EXCEEDED and 0 = OK) and the meaning of the bit are shown in the table below. For R5: Bit0 Bit1 Bit2 Bit3 Bit4 C1 maximum battery insertion status C2 maximum battery insertion status C3 maximum battery insertion status C4 maximum battery insertion status C5 maximum battery insertion status For R8: Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 C1 maximum battery insertion status C2 maximum battery insertion status C3 maximum battery insertion status C4 maximum battery insertion status C5 maximum battery insertion status C6 maximum battery insertion status C7 maximum battery insertion status C8 maximum battery insertion status C9 maximum battery insertion status C10 maximum battery insertion status C11 maximum battery insertion status

30 Page 30 of 68 (β) Calculation of the harmonic registers addresses Formula for calculation of register address of Harmonic Module n-th of current line k ADDR( Hikn ) *( k 1) n n = 2,, 31 e k = 1, 2, 3 (DUCA-LCD) n = 2,, 60 e k = 1 (R8) Formula for calculation of address register of Harmonic Module n-th of voltage line k ADDR( Hvkn ) *( k 1) n n = 2,, 31 e k = 1, 2, 3 (DUCA-LCD) n = 2,, 60 e k = 1 (R8) Example of reading a block of 6 Mixed measure: Addr Func Start Start Num. Data Num. Data CRC CRC Register H Register L H L 1Fh 03h 00h C7h 00h 0Ch F7h 8Ch In the example it set a reading of 12 bytes from index 200 ( minus 1 therefore 199). Note: INVALID DATA is shown = FFFFh. Example of reading an Harmonic value: Addr Func Start Start Num. Data Num. Data CRC CRC Register H Register L H L 1Fh 03h 04h BCh 00h 02h 07h 61h In the example it set a reading of 7 th Harmonic module of current line 2: reading of 2 bytes starting from address1213 (minus 1 therefore 1212) Notes: INVALID DATA for Harmonic modules and THD values is shown = FFFFh. INVALID DATA for Real and Imaginary parts is shown = 7FFFh. If the fundamental frequency measured by the instrument is different from 50Hz or 60Hz or if the Line-neutral voltages and line currents are less than 20VRMS and 0,3ARMS the values of THD, Harmonic modules and Real / Imaginary parts will be INVALID Real and Imaginary parts of Current and Voltage harmonics for DUCA-LCD DIN

31 Page 31 of 68 Only for DUCA-LCD DIN model it is available the following table: αi 1 factor for harmonic module conversion current line 1 ( ) (only for Duca-LCD) αv 1 factor for harmonic module conversion voltage line 1 ( ) (only for Duca-LCD) Real part Harmonic H1 current line 1 (only for Duca-LCD) Imaginary part Harmonic H1 current line 1 (only for Duca-LCD) Real part Harmonic H1 voltage line 1 (only for Duca-LCD) Imaginary part Harmonic H1 voltage line 1 (only for Duca-LCD) 1608 Real and Imaginary parts Harmonic Hn current and voltage line1 (only for Duca LCD) ( ) Real part Harmonic H31 current line 1 (only for Duca-LCD) Imaginary part Harmonic H31 current line 1 (only for Duca-LCD) Real part Harmonic H31 voltage line 1 (only for Duca-LCD) Imaginary part Harmonic H31 voltage line (only for Duca-LCD) Not used αi 2 factor for harmonic module conversion current line 2 ( ) (only for Duca-LCD) αv 2 factor for harmonic module conversion voltage line 2 ( ) (only for Duca-LCD) Real part Harmonic H1 current line 2 (only for Duca-LCD) Imaginary part Harmonic H1 current line 2 (only for Duca-LCD) Real part Harmonic H1 voltage line 2 (only for Duca-LCD) - Unsigned Long - Unsigned Long - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Unsigned Long - Unsigned Long - Signed Int - Signed Int - Signed Int

32 Page 32 of Imaginary part Harmonic H1 voltage line 2 (only for Duca-LCD) 1808 Real and Imaginary parts Harmonic Hn current and voltage line2 (only for Duca LCD) ( ) Real part Harmonic H31 current line 2 (only for Duca-LCD) Imaginary part Harmonic H31 current line 2 (only for Duca-LCD) Real part Harmonic H31 voltage line 2 (only for Duca-LCD) Imaginary part Harmonic H31 voltage line (only for Duca-LCD) Not used - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int - Signed Int αi 3 factor for harmonic module conversion - Unsigned Long current line 3 ( ) (only for Duca-LCD) αv 3 factor for harmonic module conversion - Unsigned Long voltage line 3 ( ) (only for Duca-LCD) Real part Harmonic H1 current line 3 (only - Signed Int for Duca-LCD) Imaginary part Harmonic H1 current line 3 - Signed Int (only for Duca-LCD) Real part Harmonic H1 voltage line 3 (only - Signed Int for Duca-LCD) Imaginary part Harmonic H1 voltage line 3 - Signed Int (only for Duca-LCD) Real and Imaginary parts Harmonic Hn current and voltage line 3 (only for Duca- LCD) ( ) - Signed Int Real part Harmonic H31 current line 3 - Signed Int (only for Duca-LCD) Imaginary part Harmonic H31 current line - Signed Int 3 (only for Duca-LCD) Real part Harmonic H31 voltage line 3 - Signed Int (only for Duca-LCD) Imaginary part Harmonic H31 voltage line 3 - Signed Int

33 Page 33 of 68 (only for Duca-LCD) ( ) Calculation of the Real and Imaginary parts harmonic registers addresses Formula for calculation of register address of Real and Imaginary parts of n-th Harmonic of current line k ADDR[Re( Hikn )] *( k 1) 4* n n = 0,, 31 e k = 1, 2, 3 ADDR[Im( Hikn )] *( k 1) 4* n n = 0,, 31 e k = 1, 2, 3 ( ) Factor for harmonic module conversion In order to calculate the absolute values of harmonic modules of current and voltage (expressed in A and V) use the following formula including the conversion factor αi e αv (one for each phase): Hi kn 2 kn 2 kn Rei Imi * ik [A] n = 2,, 31 and k = 1, 2, *2 *10 Hi kn = module of n-th harmonic of current line k Re i kn = Real part of n-th harmonic of current line k Im i kn = Imaginary part of n-th harmonic of current line k αi k = conversion factor of current line k Hv kn 2 kn 2 kn Re v Imv * vk [V] n = 2,, 31 and k = 1, 2, * 2 *10 Hv kn = module of n-th harmonic of voltage line k Re v kn = Real part of n-th harmonic of voltage line k Im v kn = Imaginary part of n-th harmonic of voltage line k αv k = convertion factor of voltage line k Harmonic modules expressed in thousandths of the fundamental harmonic:

34 Page 34 of 68 Hikn Hikn ( ) *1000 n = 2,, 31 and k = 1, 2, 3 Hi k1 Hvkn Hvkn ( ) *1000 n = 2,, 31 and k = 1, 2, 3 Hv k1 Total Harmonic Distortion values expressed in thousandths of the fundamental harmonic: N k1 2 Hikn n 2 THDIk ( ) Hi *1000 k = 1, 2, 3 and N= 21 o 31 DUCA-LCD (see Note1) N k = 1 and N= 60 (R8) Hvkn n 2 THDVk ( ) Hv *1000 k = 1, 2, 3 and N= 21 o 31 DUCA-LCD (see Note1) k1 2 k = 1 and N= 60 (R8) Note1: in the Setup menu of the instrument is possible to set the total number of harmonics through which are calculated THD values Floating point memory map for R5 and R8 The following table indicates the correspondence between the address of the location, the number of accessible words beginning with that address, the description of the measurement value, the unit of measurement of the measurement value and the binary format. Formats of the variables passed: - Float: means a Single-precision floating-point format (32 bits), with exponent first (example: 47F1 2007h = ). Note: INVALID DATA is FFFF FFFFh, that is a Quiet NaN. Only for R5 and R8 models it is available the following table: Add. Word Measurement description Unit Float Frequency Hz Float Three-phase Equivalent Voltage V Float