Rae FMC-60, Руководство по эксплуатации

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13
Local and Remote relays
Local relays are located on the main input PCB and are designated to specific
conditions which exist with the FMC-60 system and can be programmed to be normally
energised.
Remote relays are located on one of two 32 channel relay boards and can be
programmed to be operated according to detected events which occur such as alarms
and faults. The first 16 relays can be programmed to be normally energised.
The local relays are as follows (all contacts are rated at 5A 250Vac)
Common Over range alarm will energise if any gas is over range. S.P.C.O
Common High alarm will energise if any gas is in high alarm. D.P.C.O
Common Low alarm will energise if any gas is in low alarm. D.P.C.O
Fault will de-energise if any fault exists in the system. S.P.C.O
Option 1 will energise if voting 1 conditions are met. S.P.C.O
Option 2 will energise if voting 2 conditions are met. S.P.C.O
Option 3 will energise if voting 3 conditions are met. S.P.C.O
Option 4 will energise if voting 4 conditions are met. S.P.C.O
The 64 additional remote relays which are S.P.C.O types can be programmed to operate
on an event as an individual relay 1 to 64 OR as a pattern using the first 16 relays using
engineers menu 23 Event to Relay.
Modbus set up and indicators
Modbus is a means of obtaining data from the gas detection system via a MODBUS
master controller. The FMC-60 system is a SLAVE to the commands received from the
master via the allocated RS485 twisted pair communication cables. When a command is
received on the cable, the reply is sent on the same cable thus giving rise to a half
duplex communication. For maintenance purposes, two LEDs situated on the main
processor PCB close to the connectors show when a reply is being sent on that particular
cable.
In a MODBUS system that makes use of both these cable (digitalsensor connected),
both these LEDs flash periodically to indicate successful communication. Once the
communication has started, the FMC-60 system will monitor how long since the last
command was received and if this is greater than 50 seconds a communications failure
(COMMS FAIL) alarm will occur.
Each FMC-60 system has an internal address, which is used for Modbus address.
This address and other parameters can be set and will be remembered at power up using
engineers menu 27 Setup Network. The speed of communication (baud rate expressed in
bits per second) is set using menu 34.
All communicating devices in a Modbus system should be set to the same baud rate and
the FMC-60 system is capable of supporting 19200, 9600 and 4800 baud. 9600 is set by
default.