Product Overview

7800 SERIES RM7840E,G,L,M; EC7840L RELAY MODULE
66-2027—04 4
a
The RM7840 must have an earth ground providing a connection between the subbase and the control panel or the equipment. The
earth ground wire must be capable of conducting the current to blow the 15A fast blow fuse (or breaker) in the event of an internal short
circuit. The RM7840 needs a low impedance ground connection to the equipment frame, which, in turn, needs a low impedance con-
nection to earth ground.
b
See Tables 3 and 4.
c
See form 66-1162 for terminal ratings for the EC7840L.
a
RM7840L1026 Main Flame Establishing Period (MFEP) is 10 seconds or intermittent.
* STANDBY and RUN can be an infinite time period.
** PURGE will be determined by which ST7800A purge card is selected; 15 timings are available from 2 seconds to 30 minutes.
Table 1. Terminal Ratings
c
.
Terminal No. Description Ratings
G
Flame Sensor Earth Ground
a
—
Earth G
Earth Ground
a
—
L2(N) Line Voltage Common —
3 Alarm 120 Vac, 1A pilot duty.
4 Line Voltage Supply (L1) 120 Vac (+10/-15%), 50 or 60 Hz (±10%)
5 Burner Motor 120 Vac, 9.8 AFL, 58.8 ALR (inrush).
6 Burner Controller and Limits 120 Vac, 1 mA.
7 Lockout/Running Interlock 120 Vac, 8A run, 43A inrush.
8 Pilot Valve/Ignition
120 Vac.
b
9 Main Fuel Valve
120 Vac.
b
10 Ignition
120 Vac.
b
F (11) Flame Sensor 60 to 220 Vac, current limited.
12 Firing Rate High Fire 120 Vac, 75 VA pilot duty.
13 Firing Rate Common 120 Vac, 75 VA pilot duty.
14 Firing Rate Low Fire 120 Vac, 75 VA pilot duty.
15 Firing Rate Modulate 120 Vac, 75 VA pilot duty.
16 Unused —
17 Unused —
18 Low Fire Switch Input 120 Vac, 1 mA.
19 High Fire Switch Input 120 Vac, 1 mA.
20 Preignition Interlock Input 120 Vac, 1 mA.
21 Interrupted/Intermittent Pilot Valve/First Stage Oil Valve
120 Vac.
b
22 Shutter 120 Vac, 0.5A.
Table 2. Sequence Timing For Normal Operation.
Device Initiate Standby Purge
Flame Establishing
Period
Run
Post
Purge
Timing Interlock Circuits
Firing Rate
Circuit
Energy
Saving
Prepurge
Approval
Code
BodiesPilot Main
RM7840E 10 sec. * ** 4 or 10
sec.
10 or 15 sec. * 15 sec. Preignition, Lockout,
High and Low Fire
4-wire
modulating
Yes FM/IRI
Modulating
RM7840G 10 sec. * ** 4 or 10
sec.
10, 15 sec. or
intermittent.
* 15 sec. Preignition, Running,
Low Fire
No UL/CSA
Modulating
RM/
EC7840L
10 sec. * ** 4 or 10
sec.
10 or 15
sec.
a
* 15 sec. Preignition, Lockout
High and Low Fire
No FM/IRI
Modulating
RM7840M 10 sec. * ** 4 or 10
sec.
10 sec. or
intermittent
* 15 sec. Preignition, Running,
isolated Low Fire.
2-wire isolated
On-Off-On
contacts
No UL/CSA
On-Off.