Product Overview

RM7890; RM7895 100 VAC 7800 SERIES RELAY MODULES
15 66-1195—01
Fig. 12. RM7890 sequence.
Fig. 13. RM7895 sequence.
Fig. 14. Sequence status LED.
OPERATION
Sequence of Operation
The relay modules have operating sequences as shown in
Fig. 12 through 14.
INITIATE
The relay module enters the INITIATE sequence if the relay
module verifies voltage fluctuations of +10%/-15% or
frequency fluctuations of ±10% during any part of the
operating sequence. The INITIATE sequence lasts for ten
seconds unless the voltage or frequency tolerances are not
met. When the tolerances are not met, a hold condition is
initiated and displayed on the optional KDM for at least five
seconds. When the tolerances are met, the INITIATE
POWER
00
LED
DISPLAY
OPERATING
CONTROLLER
AND LIMITS
BURNER
START
FLAME
SIGNAL
INITIATE
ALARM
POWER
STANDBY
POWER POWER
PILOT
FLAME
MAIN
PFEP
4 or 10 SEC
PILOT
FLAME
MAIN
POWER
RUN
STANDBY
10
IGNITION
INTERMITTENT PILOT
MAIN VALVE
LIMITS AND BURNER CONTROL CLOSED
9
8
10
L1
6
TO
M32664
00
POWER
SAFE-
START
MAIN FUEL VALVE WILL BE ENERGIZED DURING PFEP IF FLAME IS PROVEN.
1
1
ALARM
S S C
SAFE START CHECK
FLAME PROVING
IGN.
AIRFLOW SW. CHECK
OPERATING
CONTROLS
AND
INTERLOCKS
INITIATE
ALARM ALARM
STANDBY
POWER POWER
PILOT
FLAME
MAIN
TIMED
PURGE
ALARM
POWER
PILOT
FLAME
MAIN
RUN
STANDBY
BURNER
START
MAIN VALVE
LIMITS AND BURNER CONTROLLER CLOSED
IGN./ PILOT
SAFE START CHECK
FLAME
PROVING
SSC
LED
DISPLAY
POWER
PILOT
FLAME
MAIN
PFEP
4 OR 10 SEC
POWER
START
POWER POWER
FLAME
SIGNAL
M32665
00 00 00
10
L1
TO
6
8
4
BURNER/BLOWER MOTOR
AIRFLOW INTERLOCK CLOSED
AFSC
TO
7
6
9
SEQUENCE
STATUS
LEDs
RESET
PUSHBUTTON
FLAME
SIMULATOR INPUT
FLAME CURRENT
TEST JACKS
CAPTIVE
MOUNTING
SCREW
DUST
COVER
RELAY
MODULE
FLAME
AMPLIFIER
M8995