Honeywell 7800 Series Installation Instructions Manual page 5

Ground Type
Earth ground (subbase and relay module).
Signal ground (KDM, Data ControlBus Module™,
Communications Interface ControlBus™ Module).
Terminal No.
G
Earth G
L2(N)
3
4
5
6
7
8
9
10
F(11)
12
13
14
15
16
17
18
19
20
21
22
a
. The relay module 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 fuse (or breaker) in event of an
internal short circuit. The relay module requires a low impedance ground connection to the equipment frame, which, in turn,
requires a low impedance connection to earth ground.
b
2000 VA maximum connected load to relay module assembly.
c
See tables 4 and 5.
d
RM7845 operating frequency determined by relay module selection.
Table 2. Recommended Grounding Practices.
Table 3. Terminal Ratings.
Description
a
Flame Sensor Ground
a
Earth Ground
Line Voltage Common
Alarm
Line Voltage Supply (L1)
Burner Motor
Burner Controller and Limits
Lockout/Running Interlock
Pilot Valve/Ignition
Main Fuel Valve
—
Flame Sensor
Firing Rate High Fire
Firing Rate Common
Firing Rate Low Fire
Firing Rate Modulate
—
—
Low Fire Switch Input
High Fire Switch Input
Preignition Interlock Input
—
—
RM7845A 7800 SERIES RELAY MODULES
Recommended Practice
1. Use to provide a connection between the subbase and
the control panel of the equipment. Earth ground must be
capable of conducting enough current to blow the 20A fuse
(or breaker) in the event of an internal short circuit.
2. Use wide straps or brackets to provide minimum length,
maximum surface area ground conductors. If a leadwire
must be used, use 14 AWG copper wire.
3. Make sure that mechanically tightened joints along the
ground path are free of nonconductive coatings and
protected against corrosion on mating surfaces.
Use the shield of the signal wire to ground the device to the
signal ground terminals [3(c)] of each device. Connect the
shield at both ends of the chain to earth ground.
—
—
—
120 Vac, 1A pilot duty.
120 Vac (+10%/-15%), 50 or 60 Hz (±10%)
120 Vac, 9.8 AFL, 58.8 ALR (inrush).
120 Vac, 1 mA.
120 Vac, 8A run, 43A inrush.
120 Vac
120 Vac
—
60 to 220 Vac, current limited.
120 Vac, 75 VA pilot duty.
120 Vac, 75 VA pilot duty.
120 Vac, 75 VA pilot duty.
120 Vac, 75 VA pilot duty.
—
—
120 Vac, 1 mA.
120 Vac, 1 mA.
120 Vac, 1 mA.
—
—
5
Ratings
c
.
c
.
b,d
66-1147—1