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Ah)Ã"!!&!($'% those set forth or identified above. Asia & Pacific 3710 ACM is a trademark of Power Measurement Ltd. DF1 is a trademark of Allen- Bradley Company. Other brands and their products are trademarks of their respective QPX@SÃH@6TVS@H@IUÃ6VTUS6GD6 holders and should be noted as such.
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Jim M. Bilach Systems Engineer Ver. 1.0 : December 19, 1989 Ver. 2.0 : March 08, 1990 Ver. 3.0 : November 26, 1990...
1.0 - INTRODUCTION This document details the serial communications protocol used to pass commands, information and data between the model 3710 ACM Power Meter and the Allen-Bradley line of programmable logic controllers (PLC) and communication interface products. This document provides the information necessary for a 3rd party OEM to develop in-house software to communicate with the model 3710 ACM Power Meter.
1.2 - COMMUNICATIONS PROTOCOL REVISIONS This section details the changes made to each new version of the Serial Communications Protocol Document. Ver. 1.0 - Initial draft of the Serial Communications Protocol Document (Released 89/12/19). Ver. 2.0 - Corrected delta mode line-to-line average voltage from incorrect line-to-neutral average voltage readings in Short Real-Time Data Packet.
This protocol uses a command / reply message packet format in which the Allen-Bradley PLC transmits a command type packet to the 3710 ACM Power Meter and the 3710 ACM answers the PLC with a reply type packet. This protocol uses two of the Allen-Bradley Message Packet Formats from the PLC-2 or Basic Command Set: Unprotected Read and Unprotected Write.
2.2 - HARDWARE CONFIGURATION The following section describes the hardware configuration required to connect a single 3710 ACM Power Meter or up to 32 3710 ACM Power Meters to a single Allen-Bradley PLC through several different Allen-Bradley Communications Interface Modules.
Allen-Bradley Communication Interface and the 3710 ACM Power Meter only. THE DESTINATION ADDRESS (DST) SUB-FIELD (1 Byte) This byte contains the address of the device (PLC or Communication Interface connected to the 3710 ACM) that the packet is being sent - 11 -...
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THE SOURCE ADDRESS (SRC) SUB-FIELD (1 Byte) This byte contains the address of the device (PLC or Communication Interface connected 3710 ACM) from which packet originated. - 12 -...
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3710 while Unprotected Write delivers data to the 3710 ACM. The commands are only sent from the PLC and the replies are only sent from the 3710 ACM. THE STATUS SUB-FIELD (1 Byte) This byte indicates the status of the message transmission.
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Bradley PLC and the 3710 ACM Power Meter. Packet Data Structure In general, most data values sent to and from a model 3710 ACM consist of a 4 byte value. Each 4 byte value can be treated as two WORDS, a LOW ORDER WORD and a HIGH ORDER WORD.
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3710 ACM. The low order byte contain the even valued 3710 ACM unit address or unit id in which the PLC can uniquely identify the meter. These two bytes form the Message Type Address found later in this document.
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Data Link Escape (DLE) SUB-FIELD and the End of Text (ETX) SUB-FIELD. These two bytes are used by the Data Link Layer of Allen-Bradley Communication Interface and the 3710 ACM Power Meter only. THE DATA LINK ESCAPE (DLE) SUB-FIELD (1 Byte) This sub-field contains a single byte control character used to indicate the end of a message packet.
is equivalent to the Block Check Character (BCC) used by Allen-Bradley Communication Products. 2.4 - BROADCAST PACKETS Provisions have been made for the use of broadcast commands within the RS-485 data transfer protocol. The purpose of this is to allow all Slave devices to receive the same command from the Master station.
2.6 - 3710 ACM TIMING CONSIDERATIONS The 3710 ACM requires a 100 millisecond dead space between the end of any response packet on the RS-485 loop and the start of a new command packet sent by the Master PLC. Sequential transmissions from the Master PLC to the 3710 ACM meters must be 100 milliseconds apart (ie: 100 millisecond dead space).
3710 ACM Power Meter. Command packets sent to the 3710 ACM from the Allen-Bradley PLC and reply packets sent from the PLC to the 3710 ACM are divided into three categories according to their function: The packets listed in the first category are used to configure and set-up the 3710 ACM Power Meter prior to operation.
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Manual description on the set-up parameters). i) Read 3710 ACM Set-Up Data (Message Type Address 01XXH). This packet is issued to a model 3710 ACM Power Meter to request a packet containing the present set-up parameters. Byte 1 = 10H = Data Link Escape (DLE) control byte.
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3710 ACM Response to Read Set-Up Data. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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3710 ACM Response to Read Set-Up Data (continued). Byte 41,42 = I Out range. Byte 43,44 = I Out key. Byte 45,46 = low order word, I Out scale. Byte 47,48 = high order word, I Out scale. Byte 49,50 = standard frequency.
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Byte 13,14 = low order word, volt scale. Byte 15,16 = high order word, volt scale. Byte 17,18 = new 3710 ACM unit id ( 2 - 254 [even address] ). Byte 19,20 = amp scale. Byte 21,22 = baudrate = 1 for 110 BAUD.
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Writing 3710 ACM Set-Up Data (Message Type Address 01XXH) (continued). Byte 37,38 = I Out range. Byte 39,40 = I Out key. Byte 41,42 = low order word, I Out scale. Byte 43,44 = high order word, I Out scale.
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Byte 10 = 03H = End of Text (ETX) delimiter byte. Byte 11 = BCC ERROR CHECK. 3.1.2 - TO READ OR SET THE 3710 ACM DATE AND TIME PARAMETERS. These packets are used to read or set-up the date & time used by the 3710 ACM Power Meter.
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3710 ACM Response to Read Time. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Set 3710 ACM Time (Message Type Address 02XXH). This packet is issued to a model 3710 ACM Power Meter to set the present time used by the 3710. Byte 1 = 10H = Data Link Escape (DLE) control byte.
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3710 ACM Response to Set Time. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Read 3710 ACM Setpoints (Message Type Address 08XXH). (Setpoints 1 to 8). This packet is issued to a model 3710 ACM Power Meter to retrieve the first 8 setpoint parameters used to control the relays associated with the meter.
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3710 ACM Response to Read Setpoints (Setpoints 1 to 8). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Read 3710 ACM Setpoints (Message Type Address 09XXH). (Setpoints 9 to 17). This packet is issued to a model 3710 ACM Power Meter to retrieve the last 9 setpoint parameters used to control the relays associated with the meter.
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3710 ACM Response to Read Setpoints (Setpoints 9 to 17). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Set 3710 ACM Setpoints (Message Type Address 08XXH). (Setpoints 1 to 8). This packet is issued to a model 3710 ACM Power Meter to set the first 8 setpoint parameters in the meter. This packet sets Setpoint #1 through Setpoint #8.
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Byte 143 = BCC ERROR CHECK. vi) 3710 ACM Response to Set Setpoints (Setpoints 1 to 8). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Set 3710 ACM Setpoints (Message Type Address 09XXH). (Setpoints 9 to 17). This packet is issued to a model 3710 ACM Power Meter to set the last 9 setpoint parameters in the meter. This packet sets Setpoint #9 through Setpoint #17.
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Byte 158 = 03H = End of Text (ETX) delimiter byte. Byte 159 = BCC ERROR CHECK. viii) 3710 ACM Response to Set Setpoints (Setpoints 9 to 17). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte.
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3710 ACM Power Meter. i) Read 3710 ACM Short Real-Time Data (Message Type 03XXH). This packet is issued to a model 3710 ACM Power Meter to retrieve a condensed version of the real-time data measured by the 3710 ACM.
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Byte 14 = BCC ERROR CHECK. ii) 3710 ACM Response to Read Short Real-Time Data. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Byte 43,44 = high order word, present kilowatt demand. Byte 45,46 = (reserved for future expansion). Byte 47,48 = power factor reading. ii) 3710 ACM Response to Read Short Real-Time Data (Continued). Byte 49,50 = low order word, present alarm status.
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31 -> Reserved for future use iii) Read 3710 ACM Long Real-Time Data (Message Type 04XXH). This packet is issued to a model 3710 ACM Power Meter to retrieve a detailed account of the real-time data measured by the 3710 ACM meter.
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3710 ACM Response to Read Long Real-Time Data. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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If the 3710 ACM is operating in 3-WIRE DELTA mode (Mode 1): Byte 21,22 = low order word, present L-L voltage, phase AB. Byte 23,24 = high order word, present L-L voltage, phase AB. Byte 25,26 = low order word, present L-L voltage, phase BC.
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3710 ACM Response to Read Long Real-Time Data (Continued). If operating in 4-WIRE WYE or DEMO mode (Modes 0 or 3): Byte 21,22 = low order word, present L-N voltage, phase A. Byte 23,24 = high order word, present L-N voltage, phase A.
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3710 ACM Response to Read Long Real-Time Data (Continued). If operating in 4-WIRE WYE, 3-WIRE DELTA or DEMO mode (Modes 0, 1 or 3): Byte 49,50 = low order word, present amperage, phase A. Byte 51,52 = high order word, present amperage, phase A.
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3710 ACM Response to Read Long Real-Time Data (Continued). The following bytes are common to all modes: Byte 81,82 = low order word, total kw reading. Byte 83,84 = high order word, total kw reading. Byte 85,86 = low order word, kw reverse reading.
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3710 ACM Response to Read Long Real-Time Data (Continued). If the 3710 ACM is operating in 4-WIRE WYE or DEMO mode (Modes 0 or 3): Byte 125,126 = low order word, present kva reading, phase A. Byte 127,128 = high order word, present kva reading, phase A.
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3710 ACM Response to Read Long Real-Time Data (Continued). The remaining section the packet is common to all voltage modes of the 3710 ACM Power Meter. Byte 149,150 = present neutral amperage, I4. Byte 151 = Relay #1 status byte.
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Relay Status Bytes Bit Position A) 00 -> Released 01 -> Operated 10 -> Forced Released 11 -> Forced Operated Status Input Status Byte Bit Position | B | C | D | E B) Status Input #4 C) Status Input #3 D) Status Input #2 E) Status Input #1 = 0 ->...
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Read 3710 ACM Status (Message Type Address 0AXXH). This packet is issued to a model 3710 ACM Power Meter to retrieve the status information on the relays, status inputs & setpoints on the model 3710 ACM Power Meter.
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3710 ACM Response to Status request. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Installation and Operation Manual for further information on the event logs. The 3710 ACM can store up to 50 events in its event log which is located in NON VOLATILE RAM. The logs contain too much information to fit into one packet so the master terminal must specify which information it wants.
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Read 3710 ACM Event Log (Message Type Address 05XXH). (Events 1 to 18). This packet is issued to a model 3710 ACM Power Meter to retrieve the eighteen most recent event logs (Events 1 to 18) stored by the meter.
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3710 ACM Response to Read Event Log. (Events 1 to 18). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Read 3710 ACM Event Log (Message Type Address 06XXH). (Events 19 to 36). This packet is issued to a model 3710 ACM Power Meter to retrieve the next eighteen most recent event logs (Events 19 to 36) stored by the meter.
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3710 ACM Response to Read Event Log. (Events 19 to 36). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Read 3710 ACM Event Log (Message Type Address 07XXH). (Events 37 to 50). This packet is issued to a model 3710 ACM Power Meter to retrieve the last fourteen event logs (Events 37 to 50) stored by the meter.
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3710 ACM Response to Read Event Log. (Events 37 to 50. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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E) 5 bits -> Day F) 4 bits -> Month G) 2 bits -> Unused Event Flag Value Bit Position A | B | C | | E | A) Relay Status #3 B) Relay Status #2 C) Relay Status #1 = 0 ->...
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35 -> Unused 36 -> Setpoint Under Voltage Phase A 37 -> Setpoint Under Voltage Phase B 38 -> Setpoint Under Voltage Phase C 39 -> Unused Event Code Value (continued) 40 -> Setpoint Voltage Unbalance Phase A 41 -> Setpoint Voltage Unbalance Phase B 42 ->...
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Read 3710 ACM Max/Min Log without Reset (Message Type Address 0CXXH). (First 14 Elements). This packet is issued to a model 3710 ACM Power Meter to retrieve the first 14 elements of the max/min data stored by the meter without resetting the max/min log data.
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3710 ACM Response to Read Max/Min Log without Reset. (First 14 Elements). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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Read 3710 ACM Max/Min Log without Reset (Message Type Address 0DXXH). (Last 7 Elements). This packet is issued to a model 3710 ACM Power Meter to retrieve the last 7 elements of the max/min data stored by the meter without resetting the max/min log data.
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3710 ACM Response to Read Max/Min Log without Reset. (Last 7 Elements). Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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G) 2 bits -> Unused Max/Min Packet Structure The location of data is dependant on which voltage mode the 3710 ACM Power Meter is operating in. If the 3710 ACM is operating in 3-WIRE DELTA mode (Mode 1): Element # 1st Packet 2nd Packet...
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If operating in 4-WIRE WYE or DEMO mode (Mode 0 or 3): Element # 1st Packet 2nd Packet Volts (L-N) Phase A Power Factor Volts (L-N) Phase B Amp Demand Volts (L-N) Phase C KW Demand Volts (L-N) Average Amperage I4 Volts (L-L) Phase AB (Reserved) Volts (L-L) Phase BC...
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Read 3710 ACM Max/Min Log with Reset (Message Type Address 0EXXH). (First 14 Elements). This packet is issued to a model 3710 ACM Power Meter to retrieve the first 14 elements of the max/min data stored by the meter &...
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Read 3710 ACM Max/Min Log with Reset (Message Type Address 0FXXH). (Last 7 Elements) This packet is issued to a model 3710 ACM Power Meter to retrieve the last 7 elements of the max/min data stored by the meter &...
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This packet is used to clear the KW HOURS parameter stored by the model 3710 ACM Power Meter. i) Clear 3710 ACM KW Hour (Message Type Address 10XXH). This packet is issued to a model 3710 ACM Power Meter to clear the KW Hour reading stored by the meter. Byte 1 = 10H = Data Link Escape (DLE) control byte.
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3710 ACM Response to Clear KW Hour Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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This packet is used to clear the KVAR HOURS parameter stored by the model 3710 ACM Power Meter. i) Clear 3710 ACM KVAR Hour (Message Type 11XXH). This packet is issued to a model 3710 ACM Power Meter to clear the KVAR Hour reading stored by the meter. Byte 1 = 10H = Data Link Escape (DLE) control byte.
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3710 ACM Response to Clear KVAR Hour Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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3.4.3 - FORMAT OF THE 3710 ACM CONTROL RELAY PACKET. This packet is used to control the operations of the 3 relays used by the model 3710 ACM Power Meter. i) Control 3710 ACM Relays (Message Type Address 12XXH). Byte 1 = 10H = Data Link Escape (DLE) control byte.
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3710 ACM Response to Controlling Relays. Byte 1 = 10H = Data Link Escape (DLE) control byte. Byte 2 = 02H = Start of Text (STX) delimiter byte. Byte 3 = (DST) - destination address byte of message packet.
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This packet is used to clear the Status #1 (S1) counter stored by the model 3710 ACM Power Meter. i) Clear 3710 ACM Status #1 Counter (Message Type 13XXH). This packet is issued to a model 3710 ACM Power Meter to clear the Status #1 counter reading stored by the meter. Byte 1 = 10H = Data Link Escape (DLE) control byte.
3.4.4 i 14XX Not Used 15XX Not Used 7FFE Not Used Message Types designated ’Not Used’ may not be used in modifications of the present communication protocol using the model 3710 ACM Power Meters which communicate with Allen-Bradley Communication Interface Products.
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