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Fireye Nexus NX6100 Series Manual

Modbus rtu/tcpip, and bacnet/ip communications
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MOD-6001
September 24, 2018
NEXUS
NX6100/PPC6000 SERIES
MODBUS RTU / TCPIP,
and BACNET/IP
COMMUNICATIONS
DESCRIPTION
The MODBUS interface is designed to c onnect Fireye's NX6100 or PPC6000 Nexus
Controllers to other devices using the 'MODBUS RTU' or 'MODBUS TCP' protocols, using
3 wire RS485. This bulletin shows connections and the available MODBUS memory map for these
controls only.
NX6100/PPC6000 series controllers may be connected to a MODBUS communications system to
enable data collection and limited control functions. The controllers are connected to the MOD-
BUS via the Isolated RS485 Communications terminals on the NX6100 or PPC6000. The MODBUS
function requires a daughter board to be fitted to each controller.
The protocol supported is MODBUS RTU and the data configuration supported is 8-bits, no parity,
1-stop bit. This is the simplest and most common data configuration because the MODBUS protocol
includes 'crc' to ensure data packet integrity.
A network of up to 14 Fireye Nexus NX6100 or PPC6000 controls can be linked toMODBUS.
Consideration needs to be given to the total number of registers to be communicated, refer to page 4
for further details.
MODBUS RTU can be accessed via two daughter boards for the NX6100 or PPC6000. The NXD-
BMB (MODBUS only) or NXDBVSD (MODBUS and variable speed drive) allow access to the
NX6100/PPC6000 through the isolated RS485 terminals. See Figure 1, Section 1.2. Also, refer to
the appropriate bulletin, NEX-6101 or PPC-6001.
The touch-screen NXTSD104 or NX6330 is required to use BACNET/IP because it provides the
Ethernet interface. The protocol is implemented by the firmware running on the touch-screen hard-
ware. BACNET/IP is the only form of the BACNET protocol available for the 6000 series.
1

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  • Page 1 'crc' to ensure data packet integrity. A network of up to 14 Fireye Nexus NX6100 or PPC6000 controls can be linked toMODBUS. Consideration needs to be given to the total number of registers to be communicated, refer to page 4 for further details.
  • Page 2 Before attempting to install, commission or operate this equipment all relevant sections of this document must be read and fully understood. If in doubt about any requirements consult Fireye. Installation, commissioning or adjustment of this product MUST be carried out by suitably trained engineers or personnel qualified by training and experience.

  • Page 3: Table Of Contents

     Table of contents Please read the safety information at the front of this manual before proceeding Introduction Compatibility and Conventions Overview Wiring and Hardware Configuration MODBUS cables Screen termination RS485 serial communications termination resistor Controller Configuration Overview Entering the Parameters General 3.3.1.1 Entering commission ratio mode...

  • Page 4: Introduction

     Introduction 1.1 Compatibility and Conventions MODBUS RTU communication with NX6100/PPC6000 series controllers is compatible with NX6100 or PPC6000 at firmware revision 1.2 or greater. Engineer's Key EK55 indicates the firmware version. See Sec- tion 4 and 6.6 of the relevant NX6100 or PPC6000 bulletin for more information. The NX6100/PPC6000 require the use of either the NXDBMB (MODBUS only) or the NXDBVSD (MODBUS and Variable Speed Drive) daughter boards.

  • Page 5: Wiring And Hardware Configuration

    2. Wiring and Hardware Configuration 2.1 MODBUS cables FIREYE recommends that RS485 MODBUS cables should be overall 'braid' screened, PVC insulated, 3- core of 24 AWG (7/0.2mm) wire minimum. This cable may be run adjacent to, and/or in the same conduit as high voltage wiring.

  • Page 6: Rs485 Serial Communications Termination Resistor

    If a FIREYE device is at the end of the bus then set both of the JP1 links to the IN position. All other controllers should have the links set to the OUT position. If only two controllers ar on the communications bus, set the termination resistors on both controllers to the IN position.

  • Page 7: Controller Configuration

     3. Controller configuration. 3.1 Overview Before configuring the NX6100/PPC6000 series controllers for MODBUS communications, the user must have a clear operating strategy defined. This strategy should define the operating speed of the bus, the bus addresses for each device on the bus and the data sets required of each bus device. Only when this informa- tion is clear should the system option parameters be set and the MODBUS system tested against the operat- ing strategy.

  • Page 8: Entering Commission Ratio Mode

     3.3.1.1 Entering commission ratio mode To enter commission mode, press the key labeled COM and select the site passcode value using the UP/DOWN keys. The site passcode has a factory default setting of 154. Enter this value as shown below. * - NOTE: If the site passcode has been changed, you will have to enter that number.
  • Page 9  Option 00.2 - Serial communications control address (0 - 15) LV1 If the control is to be connected to other equipment via the serial communications interface, it must be given a unique address using this option parameter. Additionally if more than one control unit is connected on the CAN bus (for example to share a display), the units must all have unique addresses BEFORE THEY ARE CONNECTED TO THE SAME CANbus.

  • Page 10: Modbus Rtu Data Sets

     4. MODBUS RTU Data Sets 4.1 Overview. The NX6100/PPC6000 series controllers support the following MODBUS register types : • Coils (1 to 19) - These registers can be written to by a MODBUS master to provide control of NX6100/PPC6000 series controllers. In addition these registers can be read to interrogate the last value written.

  • Page 11: Modbus System Reset And Timeout

    This register will remain 'active' controlling the burner forever unless there is no MODBUS commu- nication to this slave for three minutes. So, if there are no MODBUS read requests or write requests for three minutes, all control functions will be disabled and the FIREYE controller will operate in it's default or local state.

  • Page 12: Input Registers (3Xxx(X)) - Read From (Modbus Function Code 4)

     Table 1: Reg Address Function Details Setpoint Select 0 = Run to setpoint 1 1 = Run to setpoint 2 (use for night setback etc.) Release to Ignite If used, must be 1 to allow the burner to ignite. Low Fire Hold 0= Normal modulation.
  • Page 13  Each fault log item is an 8 byte structure stored in 4 consecutive 16 bit registers. - Register 0 = (256 * fault number) + condition. - Register 1 = (256 * year) + month - Register 2 = (256 * day) + hour - Register 3 = (256 * minute) + subset Where : - Condition = 0 for restart / reset, 1 = Cleared fault or limit (Cx), 2 = Fault (Fx) fault, 3 = Limit (Lx).
  • Page 14  Reg address Function Details Gas Pressure As on product display. Valve Prove Status As on product display. Flame Signal As on product display. Flame Signal UV level if IR is used 39 to 49 Reserved for future use 1000 Engineers Key 0 Device specific data 1001...

  • Page 15: Holding Registers (4Xxx(X)) - Write To (Modbus Function Code 6)

     4.5 Holding Registers (4XXX(X)) - WRITE TO (MODBUS function code 6) There are 20 holding (write to) registers available. These are 16 bit registers holding integer values. Writing an out of range value (for example 1000) will disable the control item and the system will go back to using its default value (immediately).

  • Page 16: Modbus Tcpip Data Sets

     5. Modbus TCPIP Data Sets 5.1 Overview. Only the register spaces for coils, input registers and holding registers are used by this system. Modbus defines each of these spaces as having 65536 possible 16 bit registers. These registers are numbered 1 to 65536 but are accessed in modbus messages by their addresses, which are always one less - so the addresses range from 0 to 65535.

  • Page 17: Coils (Read / Write) Registers (Modbus Function Codes 1 & 5)

    When the display is being used with a water-level control / expansion unit, modbus functions relating to that unit can be accessed by adding 20000 to the register address. However, no coil functions are currently supported by these units. Note : Not all items are valid for all models within the Fireye 6000 series.
  • Page 18  Table 4: Register Register Function Details number address Setpoint 0 = Run to setpoint 1. Select 1 = Run to setpoint 2 (use for night setback etc.). This register MUST NOT be written to if the built-in boiler Release to If used, must be 1 to allow the burner to ignite.

  • Page 19: Input (Read Only) Registers (Modbus Function Code 4)

     5.3 Input (READ ONLY) registers (Modbus function code 4) Sometimes these registers are referred to as registers 3xxxx registers although this notation is not part of the modbus standard and is not used here. There are many input registers available, these read current display or engineering (test) values from the system.
  • Page 20  Burner Controls Register Register Function Details Number address Profile Number As on product display. Do not use. Do not use. Modulation Rate As on product display. Spare Spare Spare Spare Gas Pressure As on product display. Valve Prove Status As on product display.
  • Page 21  Burner Controls Register Register Function Details Number address Engineers Key 39 See product manual ‘EK’ list Engineers Key 40 See product manual ‘EK’ list Engineers Key 41 See product manual ‘EK’ list Engineers Key 42 See product manual ‘EK’ list Engineers Key 43 See product manual ‘EK’...
  • Page 22  Burner Controls Register Register Function Details Number address Engineers Key 94 See product manual ‘EK’ list Engineers Key 95 See product manual ‘EK’ list Engineers Key 96 See product manual ‘EK’ list Engineers Key 97 See product manual ‘EK’ list Engineers Key 98 See product manual ‘EK’...
  • Page 23  Burner Controls Register Register Function Details Number address Engineers Key 149 See product manual ‘EK’ list Engineers Key 150 See product manual ‘EK’ list Engineers Key 151 See product manual ‘EK’ list Engineers Key 152 See product manual ‘EK’ list Engineers Key 153 See product manual ‘EK’...
  • Page 24  Table 6: Water Level Control Input Registers Water Level Controls Register Register Function Details Number Address 20025 20024 Measured water level As on product display. 20039 20038 Controller status 0 = Fault, 1 = Working Available on controller firmware 1.117 and 20043 20042 Water level setpoint...
  • Page 25  Input Registers Water Level Controls Register Register Function Details Number Address Reserved 20243 20242 Engineers Key 21 Reserved 20245 20244 Engineers Key 22 Draft Open mode 20247 20246 Engineers Key 23 Reserved 20249 20248 Engineers Key 24 Reserved 20251 20250 Engineers Key 25 Reserved...
  • Page 26  Input Registers Water Level Controls Register Register Function Details Number Address Spare 20315 20314 Engineers Key 57 CPU serial number (low 4 digits) 20317 20316 Engineers Key 58 20319 20318 Engineers Key 59 Reserved 20321 20320 Engineers Key 60 Reserved Analog Input 1.
  • Page 27  Input Registers Water Level Controls Register Register Function Details Number Address Spare 32081 20380 Engineers Key 90 Spare 20383 20382 Engineers Key 91 Spare 20385 20384 Engineers Key 92 Spare 20387 20386 Engineers Key 93 Spare 20389 20388 Engineers Key 94 Spare 20391 20390...
  • Page 28  Input Registers Water Level Controls Register Register Function Details Number Address 20457 20456 Engineers Key 128 Reserved 20459 20458 Engineers Key 129 Reserved 20461 20460 Engineers Key 130 Reserved 20463 20462 Engineers Key 131 Reserved 20465 20464 Engineers Key 132 Reserved 20467 20466...
  • Page 29  Input Registers Water Level Controls Register Register Function Details Number Address 20539 20538 Engineers Key 169 Reserved Draft Pressure 20541 20540 Engineers Key 170 Draft Output 20343 20542 Engineers Key 171 Draft Setpoint 20545 20544 Engineers Key 172 20547 20546 Engineers Key 173 Reserved...

  • Page 30: Holding (Read From / Write To) Registers (Modbus Function Codes 3 & 6)

    The remote control holding registers that can be written to (READ / WRITE). A copy of the holding registers from a fireye burner control if used. The 16 writable holding registers are register numbers 801 to 816 (address 800 to 815). These are 16 bit registers holding integer values which normally range from 0 to 999.
  • Page 31  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Drive 8 Position As on product display. Drive 9 Position As on product display. Spare Do not use Spare Do not use Measured Value As on product display. Efficiency As on product display.
  • Page 32  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Engineers Key 8 See product manual ‘EK’ list Engineers Key 9 See product manual ‘EK’ list Engineers Key 10 See product manual ‘EK’ list Engineers Key 11 See product manual ‘EK’...
  • Page 33  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Engineers Key 51 See product manual ‘EK’ list Engineers Key 52 See product manual ‘EK’ list Engineers Key 53 See product manual ‘EK’ list Engineers Key 54 See product manual ‘EK’...
  • Page 34  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Engineers Key 94 See product manual ‘EK’ list Engineers Key 95 See product manual ‘EK’ list Engineers Key 96 See product manual ‘EK’ list Engineers Key 97 See product manual ‘EK’...
  • Page 35  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Engineers Key 137 See product manual ‘EK’ list Engineers Key 138 See product manual ‘EK’ list Engineers Key 139 See product manual ‘EK’ list Engineers Key 140 See product manual ‘EK’...
  • Page 36  (BURNER CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Engineers Key 180 See product manual ‘EK’ list Engineers Key 181 See product manual ‘EK’ list Engineers Key 182 See product manual ‘EK’ list Engineers Key 183 See product manual ‘EK’...
  • Page 37  (WATER LEVEL CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address Economiser heat 20060 20059 recovered % OPTIONAL 20101 20100 Engineers Key 0 See water level manual ‘EK’ list 20102 20101 Engineers Key 1 See water level manual ‘EK’ list 20103 20102 Engineers Key 2...
  • Page 38  (WATER LEVEL CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address 20142 20141 Engineers Key 41 See water level manual ‘EK’ list 20143 20142 Engineers Key 42 See water level manual ‘EK’ list 20144 20143 Engineers Key 43 See water level manual ‘EK’...
  • Page 39  (WATER LEVEL CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address 20185 20184 Engineers Key 84 See water level manual ‘EK’ list 20186 20185 Engineers Key 85 See water level manual ‘EK’ list 20187 20186 Engineers Key 86 See water level manual ‘EK’...
  • Page 40  (WATER LEVEL CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address 20228 20227 Engineers Key 127 See water level manual ‘EK’ list 20229 20228 Engineers Key 128 See water level manual ‘EK’ list 20230 20229 Engineers Key 129 See water level manual ‘EK’...
  • Page 41  (WATER LEVEL CONTROLS) READ HOLDING ONLY REGISTERS Register Register Function Details Number Address 20271 20270 Engineers Key 170 See water level manual ‘EK’ list 20272 20271 Engineers Key 171 See water level manual ‘EK’ list 20273 20272 Engineers Key 172 See water level manual ‘EK’...
  • Page 42 808 – 816 807 – 815 Reserved for future use. Burnerlogix registers only available with NXTSD104 touchscreen : Table 10: READ ONLY HOLDING Only available when used in REGISTERS (FIREYE) conjunction with FIREYE PPC6000 / Burnerlogix. Register Register Function Details Number Address...

  • Page 43: Read Discrete Inputs (Function Code 2)

     5.5 Read Discrete Inputs (Function Code 2) NXTSD104 and NX6330 ONLY. NOT CURRENTLY AVAILABLE ON NX6110 or NX6220. Modbus function code 2 can be used the read the status of the touch-screens on-board line voltage inputs (if present). These inputs are typically used to read plant status signals and are available on the screen under the 'Plant Inputs' menu (select 'Screen Inputs').
  • Page 44  Discrete Input Status Register Function Details Register Address Number Positions proved EK21(see manual) Fault Alarm EK22 (see manual) Oxygen Trim Enabled EK23(see manual) Oil Warming Active EK24(see manual) Fan relay status 1 = relay ON Ignition relay status 1 = relay ON Pilot valve relay status 1 = relay ON Gas valve 1 relay status...

  • Page 45: Bacnet/Ip Interface

     BACNET/IP Interface 6.1 Overview BACNET/IP is available in NXTSD104 / NX6330 touch-screens with firmware version 2.200 and higher. Version 2 screens (firmware version >= 2.000) can be updated using a USB drive. Version 1 touch-screens cannot be updated to support BACNET/IP. Before use, BACNET must be enabled from the 'Configuration - Ethernet' screen : 6.2 Implementation Details Device objects / Instances...
  • Page 46  This is a virtual network implemented within the touch-screen. It provides no function other than to give access to two more devices which may or may not be routed to physical controls : Device 1501 : This device will have a BACNET device number one greater than the instance number of the router device.

  • Page 47: Description Of Objects

     6.3 Description of Objects Analog Values (object type 2). These values are listed below. Note that not all parameters will be available since this will depend on the system configuration. The following properties are most useful for these objects : •...
  • Page 48  Object Number Function Analog Input 1 Analog Input 2 Spare Spare Gas Pressure Valve Prove Status Flame Signal Flame Signal Combustion air pressure Second Gas pressure Spare Spare Spare Spare Spare Spare Spare Spare Spare Water-level (from waterlevel expansion unit) TDS (total dissolved solids –...
  • Page 49  Analog Inputs (Object type 0) In most cases, these objects will not be used. There are 16 objects available to read extra values from the sys- tem 'engineers key' list. Since there are over 200 of these parameters available, it is not practical to provide an object for each.
  • Page 50  Binary Outputs (Object type 4) These objects can be used to override digital control functions of the connected controls. There are 16 objects available. Object Function Details Number Setpoint Select 0 = Run to setpoint 1. 1 = Run to setpoint 2 (use for night setback etc.). This object MUST NOT be written to if the built-in boiler sequencing system is being used, Release to Ignite...

  • Page 51: Bacnet Protocol Conformance Statement

     6.4 BACnet Protocol Implementation Conformance Statement BACnet Standardized Device Profile (Annex L): NONE BACnet Operator Workstation (B-OWS) BACnet Advanced Operator Workstation (B-AWS) BACnet Operator Display (B-OD) BACnet Building Controller (B-BC) BACnet Advanced Application Controller (B-AAC) BACnet Application Specific Controller (B-ASC) BACnet Smart Sensor (B-SS) BACnet Smart Actuator (B-SA) List all BACnet Interoperability Building Blocks Supported (Annex K): NONE...

  • Page 52: Specification

     7. Specification. 7.1 MODbus RTU MODBUS RTU, 4800/9600/19200 baud, 8-bit, No parity, 1 stop bit. Protocol MODBUS Functions supported: 1 – Read Coils 3 – Read Holding Registers 4 – Read Input Registers 5 – Write to Coils 6 – Write to Holding Registers RS485 Interface 2-wire plus 0Vdc.

  • Page 53: Appendix - Communications

     8. Appendix - Communications 8.1 E110 Flame Monitor. SETUP Each E110 connected to the MODBUS communication bus must have a unique address. This is set using the ED510 display module. Scroll to PROGRAM SETUP, enter this sub-menu, scroll to UNIT ADDRESS, press and release the RESET key to obtain the desired address.
  • Page 54  MESSAGE WORD RESPONSE VALUE ADDRESS REQUESTED Most Recent Returns complete lockout description of stored lockout history. Lockout Data Includes lockout message, lockout module, @ burner hours, and @ 2nd Most Recent Lockout Data 3rd Most Recent Lockout Data 4th Most Recent Lockout Data 5th Most Recent Lockout Data...
  • Page 55 For the INPUTS, a 1 in the interlock position defines the interlock as being on or active where a 1 in any bit position in the OUTPUT register signifies the relay as being energized. - Refer to Fireye bulletin E-3001 for terminal designations INPUTS...
  • Page 56  EXPLANATION OF LOGSTAT IN E110 STSTEMS Table 14: LOGIC DISPATCHER VALUE MODULE FUNCTION MPOSTIDLE MPREPURGE1 Wait for air flow and/or high fire switch to close MPURGE Open Damper Purge MPOST PURGE Low Fire Purge MTFI Pilot Trial MTFMF Main Trial MAUTO AUTO MSHTDWN1...
  • Page 57  Message Table Table 15: TYPE AND MESSAGES E110 FLAME-MONITOR MESSAGES L1-13 OPEN HOLD FALSE FLAME- STANDBY LOW FIRE PURGE HOLD D-8 LIMIT OPEN- PURGE HOLD 3-P AIR FLOW OPEN LOCKOUT LINE FREQUENCY NOISE DETECTED LOCKOUT FLAME FAIL - PTFI CHECK UNIT ADDRESS HOLD M-D LIMIT OPEN IGNITION TIMING - PTFI...
  • Page 58  TYPE AND MESSAGES 3-P HIGH TEMPERATURE 3-P AUX #4 OPEN 3-P AUX #5 OPEN 3-P AUX #6 OPEN 3-P FUEL SELECT SYSTEM DIAGNOSTIC MESSAGES LOCKOUT CHECK CHASSIS LOCKOUT CHECK PROGRAMMER LOCKOUT CHECK AMPLIFIER LOCKOUT CHECK EXPANSION MODULE LOCKOUT AMPLIFIER AUTO CHECK FAIL LOCKOUT SCANNER NOISE LOCKOUT CHECK SCANNER E300 EXPANSION MODULE HOLD MESSAGES...

  • Page 59: Yb110 Burnerlogix

    12 connections, the outside contacts are connected together and are designated as “A” or “+” while the inside contacts are connected together and are designated as “B” or “-”. Fireye supplies the ED512 cables in various lengths with RJ-12 plugs on each end. Refer to bulletin E-8002 for additional...
  • Page 60 8th Most Recent Lockout Data 40064 9th Most Recent Lockout Data 40070 10th Most Recent Lockout Data 40076 40080 Reserved for Fireye use INTERLOCK ANNUNCIATOR 40901 1 - 3 Returns lower, middle and upper interlock annunciator (YZ300) registers. 40902 1 - 2...
  • Page 61  The BurnerLogix stores its burner on time (7 powered) and system on time (L1 powered) in minutes. For display purposes, the programmer converts this to hours. The information being supplied by MOD- BUS will be the actual time in minutes and it is up to the communicating device to do the conversion. Since the maximum value stored in the BurnerLogix is 9,999,999 minutes, the maximum value in hex therefore is 98967FH and comprises two data words.
  • Page 62  OUTPUTS (4008) Table 18: Bit 15 Bit 11 Bit 8 Term A Term11 Term X Term 12 Alarm Auto High Fire Low Fire Bit 7 Bit 3 Bit 0 Term W Term 7 Term M Term 6 Term 5 Internal Delayed Main...
  • Page 63  EXPLANATION OF LOGSTAT IN YB110 SYSTEMS LOGSTAT is an indication of what logic module the control is currently operating in during its cycle and is used for diagnostic purposes only. If a lockout occurs the current value of LOGSTAT is stored as part of the lockout information.
  • Page 64  Table 21: BURNERLOGIX MESSAGES T16 M-D LIMIT OPEN - AUTO HOLD FALSE FLAME- STANDBY LOW FIRE PURGE HOLD M-8 LIMIT OPEN- PURGE See Interlock Annunciation Message Table T16 M-D LOW LIMIT - AUTO LOCKOUT FLAME FAIL - PTFI T16 INPUT CLOSED HOLD M-D LIMIT OPEN IGNITION TIMING - PTFI CHECK FLAME SIGNAL - MTFI...
  • Page 65  BURNERLOGIX MESSAGES See Interlock Annunciation Message Table LOCKOUT CHECK EXPANSION MODULE LOCKOUT CHECK WIRING LOCKOUT CHECK FUSE LOCKOUT CHECK SCANNER PURGE INTERLOCK RELATED MESSAGES HOLD M-8 LIMIT CLOSED LOCKOUT M-8 LIMIT CLOSED HOLD M-D LIMIT CLOSED LOCKOUT M-D LIMIT CLOSED Reserved for future use Reserved for future use LOCKOUT FLAME FAIL - PILOT...
  • Page 66 Fireye warranty, as stated in its General Terms and Conditions of Sale, pertains only to the Fireye products and not to any other equipment or to the combined system or its overall performance.

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