Geh-6491

Transcript

g GEH–6491B POWER LEADER™ ® Modbus Concentrator User’s Guide GEH–6491 WARNINGS, CAUTIONS, AND NOTES AS USED IN THIS PUBLICATION WARNINGS Warning notices are used in this publication to emphasize that hazardous voltages, currents, or other conditions that could cause personal injury exist in this equipment or may be associated with its use. Warning notices are also used for situations in which inattention or lack of equipment knowledge could cause either personal injury or damage to equipment. CAUTIONS Caution notices are used for situations in which equipment might be damaged if care is not taken. NOTES Notes call attention to information that is especially significant to understanding and operating the equipment. This document is based on information available at the time of its publication. While efforts have been made to ensure accuracy, the information contained herein does not cover all details or variations in hardware and software, nor does it provide for every possible contingency in connection with installation, operation, and maintenance. Features may be described herein that are not present in all hardware and software systems. GE Electrical Distribution & Control assumes no obligation of notice to holders of this document with respect to changes subsequently made. GE Electrical Distribution & Control makes no representation or warranty, expressed, implied, or statutory, with respect to, and assumes no responsibility for the accuracy, completeness, sufficiency, or usefulness of the information contained herein. No warrantees of merchantability or fitness for purpose shall apply. REFERENCES POWER LEADER™ is a registered trademark of GE Company. Modbus RTU is a registered trademark of AEG Schneider Automation. For details of the Modbus RTU protocol, refer to PI-MBUS-300 Rev. E from Modicon/AEG Schneider Automation. For details of RS485 communications, refer to the EIA-485 standard. For details of the Modbus RTU register maps available in the concentrator, please refer to GEH-6508, Modbus Concentrator Protocol Guide. ©Copyright 1996 GE Company All Rights Reserved i POWER LEADER Modbus Concentrator Table of Contents Chapter 1 – Introduction 1–1 Overview................................................................................................................................... 1 1–2 Physical Description................................................................................................................ 2 1–3 Specifications........................................................................................................................... 4 1–4 Environmental Requirements................................................................................................ 4 1–5 Glossary .................................................................................................................................... 4 Chapter 2 – Installation 2–1 Mounting ................................................................................................................................. 5 2–2 Control Power Connections ................................................................................................... 5 2–3 Commnet Connections........................................................................................................... 5 2–4 Modbus Connection ............................................................................................................... 5 RS485 Grounding Considerations.................................................................................... 6 RS485 Termination Considerations................................................................................. 6 2–5 Earth Ground Connection ..................................................................................................... 6 2–6 Wiring Rules for commnet Segments .................................................................................... 7 Chapter 3 – Configuration 3–1 Modbus Concentrator Configuration ................................................................................... 9 3–2 Manual Configuration............................................................................................................ 9 3–3 Modbus Address Assignment ................................................................................................. 9 3–4 Baud Rate Specification ......................................................................................................... 9 3–5 Commnet Device Address Assignment ............................................................................... 11 Automatic Device Address Configuration..................................................................... 12 Manual Device Address Configuration.......................................................................... 12 Chapter 4 – Operation ............................................................................................. 13 Chapter 5 – Errors and Diagnostics ....................................................................... 14 Diagnostic LEDs .............................................................................................................. 14 Commnet Segment Diagnostics...................................................................................... 14 RS485 Communication Status ........................................................................................ 14 Modbus Concentrator Operation Status........................................................................ 14 Chapter 6 – Troubleshooting Guide....................................................................... 15 Configuration Worksheet ....................................................................................... 16 ii POWER LEADER Modbus Concentrator List of Figures and Tables List of Figures 1. POWER LEADER Modbus Concentrator. ........................................................................................................ 1 2. Typical network connections through a Modbus Concentrator..................................................................... 2 3. Side view of the Modbus Concentrator, showing dimensions......................................................................... 3 4. Front view of Modbus Concentrator, showing dimensions. ............................................................................ 3 5. Hole pattern for mounting the Modbus Concentrator. .................................................................................. 5 6. 12-terminal connector for up to four commnet segments............................................................................... 5 7. Modbus RTU network connectors..................................................................................................................... 5 8. RS485 network wiring. ........................................................................................................................................ 6 9. Termination of the network at the last device. ................................................................................................ 6 10. Configuration mode menu structure. ........................................................................................................... 10 List of Tables 1. POWER LEADER commnet devices supported by the Modbus Concentrator. ............................................ 1 2. Examples of Modbus RTU compatible devices................................................................................................ 2 3. POWER LEADER Modbus Concentrator specifications. ................................................................................ 4 4. POWER LEADER Modbus Concentrator environmental requirements........................................................ 4 5. Diagnostic messages corresponding to LED status on commnet segments................................................. 14 iii POWER LEADER Modbus Concentrator Chapter 1 – Introduction 1–1 Overview The GE POWER LEADER™ Modbus® Concentrator (catalog number PLZOOMG01), shown in Figure 1, is a microprocessor-based device that provides connections for 1 to 32 POWER LEADER communication network (commnet) devices to the industry-standard Modbus RTU network. Up to 215 commnet devices can be connected to a single Modbus RTU network through multiple Modbus Concentrators. The highspeed Modbus RTU network provides a performance gain of up to 20 times over an equivalent commnet network. Device Description POWER LEADER EPM Full-function, three-phase electronic meter with optional pulse initiation; simple retrofit to existing electromechanical installations. See GEH–6302 for a full description. POWER LEADER Meter Full-function three-phase meter with optional protective relaying and waveform capture. See GEH–5892. POWER LEADER MDP Overcurrent Relay Three-phase and ground protection against overloads and rapid detection of short circuits. See GEK–100682. Spectra ECM™ Advanced motor protection in fullvoltage-nonreversing (FVNR) and full-voltage-reversing (FVR) combination starter applications. See GEH–6435. MicroVersaTrip™ trip unit Overcurrent protection and optional in AKR, Power Break®, full-function metering and protective and Power Break® II relaying. See GEH–6273. insulated-case circuit breakers. MicroVersaTrip™ trip unit Overcurrent protection and optional in Spectra RMS™ full-function metering and protective molded-case circuit relaying. See GEH–5934. breakers Table 1. POWER LEADER commnet devices supported by the Modbus Concentrator. Figure 1. POWER LEADER Modbus Concentrator. The Modbus Concentrator strictly conforms to the Modbus RTU protocol, providing the capability to tie the comprehensive line of POWER LEADER commnet devices into an RS485-based powermanagement network. The concentrator allows seamless integration of POWER LEADER commnet devices with Modbus RTU-compatible devices in new or existing SCADA or DCS systems. Table 1 lists the full line of POWER LEADER commnet devices supported by the Modbus Concentrator. Table 2 contains a partial list of devices that are compatible with the concentrator and conform to the Modbus RTU standard. NOTE: PMCS 5.0 is certified for use with power management components manufactured 5/13/96 or later. If your system interfaces to: 1) any trip units, meters, or relays manufactured prior to 5/13/96, or 2) any Spectra RMS™ Circuit Breakers with MicroVersaTrip PM™ Trip Units, please contact the POWER LEADER Customer Support Center at 1-800-843-3742. Figure 2 illustrates a typical commnet network connected to a high-speed Modbus RTU network through a Modbus Concentrator. 1 POWER LEADER Modbus Concentrator Chapter 1 – Introduction 1–2 Physical Description Device Description EPM 3710 Full-function, three-phase electronic meter with optional pulse initiation, waveform capture, data logging, and protective relay outputs. EPM 3720 Full-function, three-phase electronic meter with optional pulse initiation waveform capture, data logging, protective relay outputs, and harmonic distortion measurements. MULTILIN 269 Plus Motor Management Relay Protection for medium-voltage industrial motors and associated mechanical systems. MULTILIN 565 Feeder Management Relay Complete time-overcurrent phase and ground protection by monitoring feeder phase current and ground current. Fanuc 90/30 PLC Programmable logic controller for applications from simple relay replacement to midrange process control. Fanuc 90/70 PLC Figures 3 and 4 show the dimensions of the Modbus Concentrator. The display, keypad, and connections for communications and control power are located on the front of the enclosure, as outlined below: • The four-character LED display is used for configuration and for status messages during operation. Four keys labeled SELECT, s, t, and ENTER are used for entering the addresses of attached POWER LEADER commnet devices and the address and baud rate of the Modbus Concentrator on the Modbus RTU network. • Ten pairs of LEDs provide visual status information: one pair for each commnet segment status, one pair for the RS485 communication status, and one pair for operational status. All LEDs should be green or off during normal operation. • A set of three terminals for AC or DC control power input are provided. Programmable logic controller with multiple processors and programming capabilities for large, high-speed applications. • Two 12-terminal connectors for eight commnet segments, labeled Segment A to Segment H, support as many as four commnet devices each. Table 2. Examples of Modbus RTU compatible devices. • Two three-terminal connectors providedaisychained input and output connections to the Modbus RTU network. Modbus net wor k connect s RS485 nati ve devi ces Host MULTILIN 565 FEEDER MANAGEMENT RELAY POWER MEASUREMENT LI MITED 3720 ACM EPM 3710 or 3720 GE Fanuc 90/30 or 90/70 Mul ti l i n 565 g POWER LEADER Commnet Con necti ons Modbus® Concentrator Mi croVersaTrip trip units RS485 connect i on t o Modbus Concentr at or RS485 In /Out DI SPL AY STATUS LE Ds Mi cr oVersaTr i p tri p units Sel ect s Contr ol Power 85Vac-265 Vac 10 0Vd c- 25 0Vdc t En ter Commnet Con necti ons POWER LEADER Met er Contr ol Power Commnet segments t o POWER LEADER Commnet devi ces Figure 2. Typical network connections through a Modbus Concentrator. 2 POWER LEADER El ectr oni c Power Meter POWER LEADER Modbus Concentrator Chapter 1 – Introduction Mount i ng Sur f ace 3.400 i n. 6. 000 i n. 0. 640 i n. Gr oundi ng Scr ew 2.137 i n. Figure 3. Side view of the Modbus Concentrator, showing dimensions. 10.500 in. 10.000 in. 9.312 in. 3.466 in. 0. 250 in. 0.213 di a. 2.520 in. 0.250 dia. 0.64 in. g 2.312 in. + - S + - S + - S + - S Segment Segment Segment Segment A B C D Commnet Connecti ons POWER LEADER Modbus® Concentrator + - S RS- 485 In + - S RS- 485 Ou t DI SPLAY STATUS LE Ds 6.000 in. 5.904 in. 2.312 in. Commnet Connecti ons Contr ol Power 85Va c- 265Vac 100Vdc- 250Vdc s Segment Segment Segment Segment E D G H + - S + - S + - S + - S 3.466 in. 0. 594 i n. Sel ect 2.520 in. 3.025 in. 3.350 in. Gr oundi ng Scr ew Figure 4. Front view of Modbus Concentrator, showing dimensions. 3 2.375 in. t Enter POWER LEADER Modbus Concentrator Chapter 1 – Introduction 1–3 Specifications 1–5 Glossary The specifications of the Modbus Concentrator are listed in Table 3. The following are definitions of some of the terms used in this document. Parameter Value Control power 85–265 Vac, 47–63 Hz; 100–250 Vdc; 20 VA min POWER LEADER commnet communications Modbus communications RS485 Modbus and commnet interconnections Standards UL: 508 & 840 CSA: C22.2 No. 14 POWER LEADER – The GE family of comprehensive power management devices and system software used to minimize downtime and overall power cost. PMCS – Power Management Control System software. SCADA (Supervisory Control And Data Acquisition) – A group of systems including power management control systems. Eight segments with up to four devices each; Mating connector: Precision Connector Designs (PCD) ELFT12260 or equivalent DCS (Distributed Control System) – A group of systems including building automation and status monitoring systems. One RS485 port, 1200 baud, 2400 baud, 4800 baud, 9600 baud, and 19.2 Kbaud; no parity, eight data bits, one stop bit. Mating connector: Precision Connector Designs (PCD) ELFT03260 or equivalent Modbus RTU (Remote Terminal Unit) – An open, industrystandard, high-performance network communications protocol developed by Modicon/AEG Schnieder Automation. Modbus-compatible device – Any device equipped with a Modbus RTU communications port. Modbus master – A host computer running PMCS software. Bare wire, AWG #12–24 RS485/EIA485 – A physical standard for multi-drop, high-speed, noise-tolerant communications over a twisted pair network; often used with the Modbus RTU protocol. UL Listed (#E146421) CSA Certified (#LR 77871-21) Table 3. POWER LEADER Modbus Concentrator specifications. commnet – A GE proprietary network communications standard. 1–4 Environmental Requirements commnet-compatible device – Any meter, relay, trip unit, or other device equipped with a commnet communications port. The environmental requirements of the Modbus Concentrator are listed in Table 4. Parameter Value Operating temperature 0° C to +70° C Storage temperature –20° C to +80° C Relative humidity 5% to 95% noncondensing Vibration response and endurance IEC 255–21–1 Severity Class 1 Fast transient surge ANSI C37.90.1 Radiated EMI withstand ANSI C37.90.2 Electrostatic discharge IEC 801–2 Severity Class 4 commnet segment – A group of one to four commnetcompatible devices (including no more than one waveform-capturing meter) with all communication ports wired to a single concentrator commnet port (A–H). Table 4. POWER LEADER Modbus Concentrator environmental requirements. 4 POWER LEADER Modbus Concentrator Chapter 2 – Installation 2–1 Mounting The hole pattern for the mounting flanges on the sides of the Modbus Concentrator is shown in Figure 5. Use #10–32 screws with flat washers, with at least two fasteners at each end of the concentrator. 10.0 i n. 0.250" dia. 2.312 in. 2.312 in. Figure 6. 12-terminal connector for up to four commnet segments. Figure 5. Hole pattern for mounting the Modbus Concentrator. 2–4 Modbus Connection 2–2 Control Power Connections Make connections to the RS485 network through the two three-terminal connectors shown in Figure 7. Connect to the three control power terminals on the front of the enclosure. The power cable terminations can be either ring or spade lugs on AWG #12–22 wire. See Section 1–3 for appropriate control power voltage ranges. The connector labeled RS485 IN is wired to the network coming from the host (or previous device), while the RS485 OUT connector is wired to the RS485 IN connector of the next Modbus device (if any). Please study and follow the RS485 grounding considerations and termination rules below to ensure the correct operation of your RS485 network. 2–3 Commnet Connections Two 12-terminal connectors, as shown in Figure 6, provide connections for up to four commnet segments each. The connectors accept bare AWG #12–24 wire. See Section 2–6 for specific wiring rules. Figure 7. Modbus RTU network connectors. 5 POWER LEADER Modbus Concentrator Chapter 2 – Installation RS485 Grounding Considerations The RS485 shield is attached to ground at the host. The shield is not connected to the RS485 IN port of the next device, but is connected to the RS485 OUT port and to a grounding screw if the shield terminal of the RS485 port is not directly grounded. This will provide an isolated ground for each device. Figure 8 illustrates correct wiring for communications and shield grounding. By following this example, a secure grounding point will be provided for each device on the network. Any surge will dissipate locally without being carried up or down the network to other devices, thus minimizing the chance for damage to devices due to surge or EMI. RS485 Host (RS485 card, RS232/RS485 converter, or Ethernet Gateway RS485 port) Network Connections: RS485 + - Shield RS485 Termination Considerations Per the EIA485 standard, the RS485 network must be terminated at both ends (Figure 8). If a Modbus Concentrator is the last device, place the supplied 120-ohm, 1/2-watt resistor between the + and connectors of the RS485 OUT port (Figure 9). 124 ohm 1/2 watt terminating resistor Two wire, twisted, shielded pair cable RS485 Device #1 Shield + Shield from host not connected RS485 Device #2 Modbus Concentrator Shield + Shield RS485 + out GND Figure 9. Termination of the network at the last device.. RS485 in Shield from host or previous device not connected 2–5 Earth Ground Connection Connect earth ground to the green-colored grounding screw on the side of the concentrator enclosure. Earth ground connection requires #14 AWG or thicker wire and a ring or spade lug. Shield to downstream devices connected at Modbus Concentrator RS485 OUT port and grounding screw NOTE: Failure to properly connect earth ground to the concentrator may result in inconsistent or noisy network communications. RS485 Device #31 Shield + - Shield from host or previous device not connected 124 ohm, 1/2 watt terminating resistor WARNING: Failure to properly connect earth ground may result in voltages hazardous to personnel and equipment being present at the concentrator enclosure. Figure 8. RS485 network wiring. 6 POWER LEADER Modbus Concentrator Chapter 2 – Installation 2–6 Wiring Rules for commnet Segments Shields grounded at multiple points may cause ground loops and communication problems. When wiring commnet devices to a Modbus Concentrator, follow the wiring rules below to ensure proper configuration and grounding of each commnet segment. NOTE: Grounding considerations for all commnet segments: DO connect all commnet shields to the appropriate shield terminals of the Modbus Concentrator. 1. Up to four commnet devices can be attached to any single commnet segment. Only one of these four devices can be a POWER LEADER Meter with Waveform Capture. POWER LEADER Repeaters and Junction/Outlet Boxes do not count as commnet devices. DO NOT connect the commnet shields atany commnet device. This may cause ground loops and erratic communication problems. For prefabricated commnet cables, cut and trim the shield wire at the end of the cable connecting to the device. DO NOT connect the commnet shields to any ground other than at the Modbus Concentrator (or theOUTPUT terminal of the Repeater; see Rule 7). 2. Ensure that all devices are uniquely addressed. The uniqueness of the address is based on comparison to all commnet and Modbus devices on the Modbus RTU network. Convert all commnet addresses to equivalent Modbus addresses (see Section 3–5 and the Configuration Worksheet at the end of this manual) and verify that all addresses are unique with respect to all other commnet and Modbus devices on the Modbus RTU network. 7. POWER LEADER Repeaters extend the wiring length of the commnet segment and provide isolation between runs of cable in a commnet segment. Repeaters do not provide for additional commnet devices on a segment or relax the unique address requirement. See GEH6502, the PMCS Network Architecture Guide, for more information on wiring considerations. 3. No connections between commnet segments are permitted, either directly or through Repeaters. 4. Commnet segments may not include any POWER LEADER Monitors or be connected to any POWER LEADER CNI cards. NOTE: Special grounding considerations for commnet segments with Repeaters: 5. Ensure that commnet segments use no more than 1000 ft of communication cable without Repeaters. Refer to GEH-5904 for appropriate wiring lengths with Repeaters. DO NOT connect the concentrator to a Repeater’s OUTPUT terminal, either directly or through a Junction/Outlet Box. This may cause ground loops and erratic communication pro blems. DO connect the concentrator to the INPUT terminal of a Repeater, either directly or through a Junction/Outlet box. The INPUT shield terminal of a Repeater is not grounded and may be connected without causing ground loops. 6. Ensure that each commnet segment has the communication cable shield grounded at only one point. The Modbus Concentrator provides an earth ground connection at each commnet segment shield terminal. Verify that all communication cable shields in the commnet segment have continuity to the appropriate segment shield terminal of the concentrator. Verify that all other communication cable shields in the commnet segment are not connected to any other ground or voltage source. Ungrounded shields do not provide efficient noise protection in the network and may cause frequent communication errors. DO connect the shield wire of the commnet cable to the shield terminal at the OUTPUT of the Repeater. This provides an earth ground for the Repeater OUTPUT communication cable. This does not violate the multiple grounding rule since theINPUT and OUTPUT terminals of the Repeater are isolated. The OUTPUT shield terminal of the Repeater is now the single grounding point for all commnet cabling from the OUTPUT of the Repeater. 7 POWER LEADER Modbus Concentrator Chapter 2 – Installation DO NOT connect the OUTPUT terminal of a Repeater to the OUTPUT terminal of a second Repeater, either directly or through a Junction/Outlet Box. This may cause ground loops and erratic communication problems. DO connect the OUTPUT terminal of a Repeater to the INPUT terminal of a second Repeater, either directly or through a Junction/Outlet Box. The INPUT shield terminal of a Repeater is not grounded and may be connected without causingground loops. DO NOT connect the commnet shields from the OUTPUT terminal of the Repeater to any ground other than theOUTPUT shield terminal of the repeater. This may cause ground loops and erratic communication problems. DO NOT connect the commnet shields at any commnet device. For prefabricated commnet cables, cut and trim the shield wire at the end of the cable connecting to the commnet device. 8. POWER LEADER Junction/Outlet Boxes may be used on commnet segments to provide for simple point-to-point wiring. NOTE: Special grounding considerations for commnet segments with Junction/Outlet Boxes: DO connect all commnet shields to the breaker receptacle(s) and the shield terminal strip inside the Junction/Outlet Box. DO NOT connect any ground to the shield terminal strip inside the Junction/Outlet Box. This may cause ground loops and erratic communication problems. 8 POWER LEADER Modbus Concentrator Chapter 3 – Configuration 3–1 Modbus Concentrator Configuration Press the ENTER key to activate any of these options, as described below. The Modbus Concentrator must be properly configured to operate on both the Modbus and commnet networks. At installation, the concentrator must be configured with a unique Modbus address, the RS485 baud rate, and the commnet addresses of all attached POWER LEADER devices. The Modbus address and RS485 baud rate must be configured manually, as described below. The commnet addresses may either be automatically detected by the concentrator or programmed manually, both of which are described below. In all cases, the configuration is saved to nonvolatile memory in the concentrator for safe retrieval in case of a power loss. Reconfiguration of the Modbus Concentrator should only be necessary after system changes. 3–3 Modbus Address Assignment A unique Modbus address is required to allow proper communication between the Modbus master and the concentrator. The valid range of Modbus addresses for a Modbus Concentrator is 1–32. Address zero is reserved for broadcast messages, per the Modbus standard. The Modbus address assigned to the concentrator must be unique to avoid communication conflicts with other Modbus devices on the RS485 network. Use the following procedure to set the RS485 network address of the concentrator: 1. Press the SELECT key to display CNFG. 2. Press ENTER to display ADDR, then press ENTER again to display the current address. Figure 10 illustrates the sequence of steps in configuration mode. 3. Press the s or t keys to scroll through the available addresses, from 1 to 32. (The factory-default address is 1.) 3–2 Manual Configuration 4. Press ENTER when the desired address appears in the display. The display flashes four times while the address is saved to non-volatile memory. When power is applied to the Modbus Concentrator, it first performs a self-test to verify that the internal devices are functional. It then continuously displays a scrolling message indicating the software revision, RS485 network address, and baud rate of the concentrator. Enter Configuration mode at any time this message is displayed by pressing the SELECT key. 5. Press SELECT again to leave Configuration mode or press s or t to go on to baud rate. 3–4 Baud Rate Specification Pressing the SELECT key displays CNFG on the fourcharacter LED display. The s or t keys will then scroll backwards or forwards through the following sequence: The RS485 baud rate must be configured so that the Modbus Concentrator matches the system baud rate. This allows the concentrator to receive and transmit data with the Modbus host at the correct system speed. The concentrator is compatible with RS485 Modbus systems communicating at 1200 baud, 2400 baud, 4800 baud, 9600 baud and 19.2 Kbaud. (The factory-default baud rate is 19.2 Kbaud.) CNFG SEGA SEGB SEGC SEGD SEGE SEGF SEGG SEGH AUTO If you have just set the concentrator address, begin with step 3; otherwise, start at step 1. 9 POWER LEADER Modbus Concentrator Chapter 3 – Configuration S CNFG E s t E ADDR E BAUD S t t 32 s 19.2 t 1200 9600 s s 2 SEGA SAD1 t E 514 t KEY s SAD4 s . .. t SEGH E S t Leave configuration mode ENTER S SELECT s UP ARROW t DOWN ARROW XXX DISPLAY s AUTO t . .. E S E AUTO|CNFG Notes 1. If user attempts to enter a duplicate comm net address, ERR will flash briefly on the display. 2. AUTO and CNFG will alternately flash on the display. S * see note 2 Leave configuration mode Figure 10. Configuration mode menu structure. 10 S * see note 1 s . .. s S E OFF t .. . E 300 t s S Leave configuration mode s E E Leave configuration mode S t s 1 POWER LEADER Modbus Concentrator Chapter 3 – Configuration [Modbus address] = [commnet address] - 267. 1. Press the SELECT key to display CNFG. Avoid Modbus and commnet address conflicts by programming all commnet addresses to have unique equivalent Modbus addresses. An example of an address conflict would be a POWER LEADER EPM with commnet address 400 and a Multilin 269+ occupying Modbus address 133. The EPM has an equivalent Modbus address of 133 which will cause communication errors between the EPM and the Multilin 269+ on the Modbus network. Resolve the conflict by changing the commnet address of the EPM or the Modbus address of the Multilin 269+ to a nonconflicting address. 2. Press ENTER to display ADDR, then s or t to toggle to BAUD. 3. Press ENTER to display the current baud rate. 4. Press s or t to toggle through the list of available baud rates; these are 1200 baud, 2400 baud, 4800 baud, 9600 baud, and 19.2 Kbaud. 5. Press ENTER when the desired baud rate appears in the display. The display flashs four times while the baud rate is saved to nonvolatile memory. Installations with multiple Modbus Concentrators also must satisfy the unique address requirement. Thus, an installation with one concentrator connected to a POWER LEADER EPM with commnet address 321 and a second concentrator with a Spectra ECM also at commnet address 321 violates the unique address requirement (both devices have equivalent Modbus addresses of 54). Resolve the conflict by changing the commnet address of the EPM or the Spectra ECM to a nonconflicting address. 6. Press SELECT again to leave Configuration mode or press s or t to go to Modbus address assignment. 3–5 Commnet Device Address Assignment A Modbus RTU network may support up to 247 devices. Each device on the network must be assigned a unique Modbus address in the range of 1–247. A Configuration Worksheet on which to record the configuration of the Modbus Concentrator and the attached commnet-compatible devices is provided in the back of this manual. To provide seamless integration of commnetcompatible devices into the Modbus RTU network, the concentrator directly maps commnet addresses to equivalent Modbus addresses. The valid range of commnet addresses recognized by the concentrator is 300–514. These addresses are one-to-one mapped to the equivalent Modbus address range of 33–247. Installations requiring more than 247 devices can be accomodated with multiple Modbus RTU networks. Refer to GEH-6502, the Power Management Control System Network Architecture Guide for a complete description of the PMCS network architecture. To determine the equivalent Modbus address from a known commnet address, simply subtract 267 from the commnet address. For example, if a commnet address is set to 500, this device’s equivalent Modbus address is 233. All communications by the Modbus master to this device use address 233. The Modbus Concentrator must be configured with the commnet addresses of all attached POWER LEADER commnet devices. Attached commnet devices must be configured to the respective commnet segment (A–H) to which the device is wired. Up to four commnet addresses are recognized per segment (including no more than one waveform-capturing meter per segment). In most cases, the simplest method for configuring commnet device addresses is the automatic configuration procedure. The commnet device To determine the commnet address from a known Modbus address, simply add 267 to the Modbus address. In all cases, any communications to a device should use the equivalent Modbus address determined through the following fomula: 11 POWER LEADER Modbus Concentrator Chapter 3 – Configuration 1. Press the SELECT key to display CNFG. addresses may always be configured manually. Procedures for both are described below. 2. Press s or t to toggle to the desired segment (SEGA through SEGH). Automatic Device Address Configuration 3. Press ENTER to display S*D# (where * refers to the selected segment, A–H, and # refers to the device number, 1–4), then s or t to toggle through the four devices on that segment. Initiate automatic configuration of the commnet addresses only after the Modbus Concentrator has been installed and wired to the appropriate commnet devices. Commnet addresses must already have been configured at each commnet device before the automatic configuration procedure is initiated. Automatic configuration erases any commnet addresses previously stored in the Modbus Concentrator and reprograms the concentrator with the commnet addresses of all detected commnet devices (automatic configuration has no effect on the RS485 baud rate or the Modbus address). 4. Press ENTER to display the current address for the selected device. A previously unaddressed device will show OFF as its address. 5. Press s or t to toggle through the list of available commnet addresses, 300 to 514. Hold the key down to scan quickly through the list. 6. Press ENTER when the desired address appears in the display. The display will flash four times while the address is saved to non-volatile memory. To initiate automatic configuration, use the following procedure: 1. Press the SELECT key to display CNFG. 7. Press s or t to select another device to address on that segment or press SELECT to configure another segment. 2. Press s or t to toggle to AUTO. 3. Press ENTER to begin the process; the display blinks the word AUTO until automatic configuration is complete (this may take as long as nine minutes). 8. Presss or t to select another segment or press SELECT to leave configuration mode. 4. Press SELECT again to leave Configuration mode. Do not modify any of the settings on any of the attached commnet devices until the automatic configuration is complete. All of the commnet segment status LEDs are lit during automatic configuration. To abort automatic configuration (and return to the prior configuration), press SELECT key during the configuration procedure. After an automatic configuration is complete, the commnet segment status LEDs show the status of each automatically configured commnet segment. Refer to Chapter 5 – Errors and Diagnostics to diagnose any configuration errors. Manual Device Address Configuration Use the following procedure to manually configure commnet device addresses: 12 POWER LEADER Modbus Concentrator Chapter 4 – Operation During normal operation, the Modbus Concentrator collects data from the attached POWER LEADER commnet devices and translates this data to the Modbus RTU protocol. Under normal operating conditions, no red status LEDs are illuminated and the four-character LED display constantly scrolls a status message listing the software revision number, the Modbus RTU address of the concentrator, and the baud rate. Also, the RS485 Modbus RTU status LED flickers green during reception or transmission of Modbus messages. The presence of any illuminated red status LED indicates an error in the configuration of the commnet addresses or an internal failure detected in the Modbus Concentrator. To diagnose and correct any of these error conditions, refer to Chapter 5 – Errors and Diagnostics and Chapter 6 – Troubleshooting Guide. 13 POWER LEADER Modbus Concentrator Chapter 5 – Errors and Diagnostics Diagnostic LEDs RS485 Communication Status A bank of ten pairs (one green and one red) of LEDs on the front panel of the Modbus Concentrator provides at-a-glance visual status information. The first eight pairs of LEDs provide status information for each of the eight commnet segments, another pair for RS485 communication status, and one pair for internal diagnostics. Table 5 explains how to read the LED status display. The green status LED for the RS485 Modbus RTU will flicker as data is received or transmitted on the Modbus network; it remains unlit if there is no activity. The red LED is unused. Modbus Concentrator Operation Status The green LED for operation status is lit when the concentrator is functioning properly. The red LED lights when there is an internal failure. Commnet Segment Diagnostics Diagnostic messages corresponding to the LED status for the commnet segments are listed in Table 5. Green Red Condition On Off Segment communications normal Off Off Segment empty or no devices configured Off Blink One or more addresses out of range, or one or more devices not responding Off On More than four devices on the segment, or More than one waveform-capturing meter on the segment Blink Blink On On Address conflict within the segment Address conflict across multiple segments, or address conflict within and across multiple segments Table 5. Diagnostic messages corresponding to LED status on commnet segments. 14 POWER LEADER Modbus Concentrator Chapter 6 – Trouble-Shooting Guide The following guide is provided for troubleshooting and isolating common problems. It does not cover every possible condition. Contact the ED&C Customer Support Center at 1-800-843-3742 if the problem is not resolved by these procedures. Symptom 1. Display blank, no lit status LEDs Possible Cause Lack of power Corrective Action Check that power wires are correctly connected. Measure voltage by probing directly on the control power terminal screws. WARNING: Voltages hazardous to personnel and equipment may be present at the power connection. 2. Operation status red LED lit or display flashes ERR 3. RS485 Modbus RTU status green LED not flashing Internal failure in Modbus Concentrator Remove and reapply power to the concentrator to see if the failure clears itself (possibly caused by external noise). Note the contents of the display and contact Customer Service if the problem persists. Faulty RS485 wiring between Check that the RS485 IN connector is properly wired and firmly seated. Test wiring for Modbus Concentrator and continuity and polarity to the Modbus master. Modbus master Modbus master malfunctioning or off 4. One or more Commnet segment status red LEDs lit or blinking Faulty commnet wiring between Modbus Concentrator and commnet device(s) Addressing problems or too many devices on segment 15 Check status of the Modbus master and verify attempted communications to the Modbus Concentrator. Check that the Commnet Segment connector is properly wired and firmly seated. Test wiring for continuity and polarity to commnet device. Refer to section 5–1 to diagnose the precise problem and correct it accordingly. POWER LEADER Modbus Concentrator Configuration Worksheet Use the following worksheet to record devices attached to the Modbus Concentrator, for reference and troubleshooting. Fill in the device type and the commnet address assigned to it, and fill in the Modbus address by subtracting 267 from the commnet address. Screen Address SAD1 Commnet Segment A Device Number 1 SAD2 A 2 – 267 SAD3 A 3 – 267 SAD4 A 4 – 267 SBD1 B 1 – 267 SBD2 B 2 – 267 SBD3 B 3 – 267 SBD4 B 4 – 267 SCD1 C 1 – 267 SCD2 C 2 – 267 SCD3 C 3 – 267 SCD4 C 4 – 267 SDD1 D 1 – 267 SDD2 D 2 – 267 SDD3 D 3 – 267 SDD4 D 4 – 267 SED1 E 1 – 267 SED2 E 2 – 267 SED3 E 3 – 267 SED4 E 4 – 267 SFD1 F 1 – 267 SFD2 F 2 – 267 SFD3 F 3 – 267 SFD4 F 4 – 267 SGD1 G 1 – 267 SGD2 G 2 – 267 SGD3 G 3 – 267 SGD4 G 4 – 267 SHD1 H 1 – 267 SHD2 H 2 – 267 SHD3 H 3 – 267 SHD4 H 4 – 267 Baud Rate Commnet Address Device Type – Address Offset = – 267 Modbus Concentrator Modbus Address (1–32) 16 Equivalent Modbus Address g GE Electrical Distribution & Control General Electric Company 41 Woodford Ave., Plainville, CT 06062 GEH-6491B 0996 © 1996 General Electric Company