System information

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3. Move the “Check-Run” switch to the Check position.
4. The display will indicate Unit Address 00 (or the current address).
5. Every time the reset button is held down for 1 second and then released will increase the address
by one.
6. Maximum address is 31. Then the address will roll over to 00.
FLAME-MONITOR MODBUS COMMUNICATIONS
The protocol to be used is Modbus RTU. This is implemented by the master (PC, PLC, etc.) issuing
a poll to the slave (Flame-Monitor) and the slave responding with the appropriate message.
A typical format of a poll request is as follows:
DST refers to the logical address of the slave.
FNC is the function being requested. FNC 03 is a read request.
ADR is the message number or register number of the data being requested. In Modbus, register
addresses begin at 40001 but is interpreted as address 00.
DAT is the number of words being requested. A word is an integer consisting of 2 bytes.
The normal response from a slave is as follows:
DBC is the data byte count being returned. It must be two times the DAT number from the poll
request.
DATA is the data returned and is always a series of 2 byte integers. If 4 words were requested then
DBC would be 8 and there would be 8 data bytes or 4 data words containing the requested data.
The format of the data is 4800,N,8,1 meaning 4800 baud, no parity, and 1 stop bit.
Below is a table of currently available messages provided by the Flame-Monitor programmers, fol-
lowed by a description where necessary.
Table 1:
DST FNC ADR
HI
ADR
LO
DAT
HI
DAT
LO
CRC
LO
CRC
HI
DST FNC DBC DATA….
HI/LO
CRC
LO
CRC
HI
MESSAGE
ADDRESS
WORD
REQUESTED
RESPONSE VALUE
00 1-6 STATUS 83 (053H) = RUN;
202 (0CAH) = LOCKOUT
01 1 MSGN Current message being displayed (see Table 1)
02 1 GSTAT Defines Timer Type
03 1 TIMER Time, Flame, Address
04 1 FLAME Flame Signal
05 1-3 LOGSTAT Current logic module, PURGE, PTFI, AUTO (see Table 2)
06 1 INPUTS Input limits state
07 1 OUTPUTS Output relays state
08 2 SYSMINS System on minutes
10 2 BNRMINS Burner on minutes
12 2 CYCLES Completed Burner Cycles
14 1 LOCKOUT COUNT Stored Lockout Count
15 1-6 LOCKOUT HISTORY Last 6 Lockouts, first word is most current lockout
21 1-2 DEVTYP Programmer device type, 5=EP, 6=EPD, 7=MicroM
22 1 AMPTYP Amplifier Type; EUVS4=0C0H;
EIR1=0A0H;
ERT1, EUV1=090H;