7800 SERIES EC7890A,B/RM7890A,B RELAY MODULE
65-0204–1
10
CAUTION
1.
Disconnect the power supply before beginning
installation to prevent electrical shock and
equipment damage. More than one power supply
disconnect may be involved.
2.
Wiring connections for the 7890 are unique;
therefore, refer to Fig. 7 or 8 for the correct
Specifications for proper subbase wiring.
3.
Wiring must comply with all applicable codes,
ordinances and regulations.
4.
Wiring, where required, must comply with NEC
Class 1 (Line Voltage) wiring.
5.
Loads connected to the 7890 must not exceed
those listed on the 7890 label or the
Specifications, see Table 1.
6.
Limits and interlocks must be rated to carry and
break current simultaneously to the ignition
transformer, pilot valve, and main fuel valve(s).
7.
All external timers must be listed or component
recognized by authorities who have jurisdiction
for the specific purpose for which they are used.
IMPORTANT
1.
For on-off gas-fired systems, some authorities who
have jurisdiction prohibit the wiring of any limit or
operating contacts in series between the flame
safeguard control and the main fuel valve(s).
2.
Two detectors can be connected in parallel with
the exception of Infrared Detectors (C7015).
3.
This equipment generates, uses and can radiate
radio frequency energy and, if not installed and
used in accordance with the instructions, may
cause interference to radio communications. It
has been tested and found to comply with the
limits for a Class A computing device pursuant to
subpart J of part 15 of FCC rules, which are
designed to provide reasonable protection
against such interference when operated in a
commercial environment. Operation of this
equipment in a residential area is likely to cause
interference; in which case, the users at their
own expense may be required to take whatever
measures are required to correct this
interference. Any unauthorized modification of
this equipment may result in the revocation of
the owners authority to continue its operation.
Humidity
Install the 7890 where the relative humidity never reaches
the saturation point. The 7890 is designed to operate in a
maximum 85% RH continuous, noncondensing moisture
environment. Condensing moisture can cause a safety
shutdown.
Vibration
Do not install the 7890 where it could be subjected to
vibration in excess of 0.5G continuous maximum vibration.
Weather
The 7890 is not designed to be weather tight. If installed
outdoors, the 7890 must be protected by an approved
weather-tight enclosure.
Fig. 6. Internal block diagram of the 7890 (see Fig. 7 for detailed wiring instructions).
CONFIGURATION
JUMPERS
MICROCOMPUTER
RESET
PUSH-
BUTTON
STATUS LEDs
SAFETY RELAY
CIRCUIT
POWER SUPPLY
OPTIONAL KEYBOARD
DISPLAY MODULE
PLUG-IN
FLAME
AMPLIFIER
RELAY
DRIVE
CIRCUIT
CONTROL
POWER
TEST
JACK
REMOTE
RESET
DDL
DDL
COMMUNICATIONS
INDICATES FEEDBACK SENSING
TO RELAY STATUS FEEDBACK
AND LINE VOLTAGE INPUTS
FIELD WIRING
INTERNAL WIRING
IGNITION
PILOT
MAIN VALVE
1K
RELAY
STATUS
FEEDBACK
AND LINE
VOLTAGE
INPUTS
LIMITS CONTROLLER
1K1
2K1
FLAME SIGNAL
TEST
PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
RM7890: 100 VAC; EC7890: 200 VAC.
RS485
1
2
3
L1
(HOT)
L2
3
6
4K1
2K2
10
8
9
4K
3K
2K
F
G
22
ALARM
3K1
4
L2
1
M11193
1
2
2
