Honeywell 7800 Series Manual page 17

Remote Mounting of Keyboard Display Module
If permitted by application approval (see Approvals), the
Keyboard Display Module can be mounted either on the
face of a panel door or on other remote locations, see
Fig. 12.
When mounting the Keyboard Display Module on the
face of a panel door, closely follow the instructions:
a. Select the location on the door panel for flush
mounting.
b. Use the Keyboard Display Module as a template,
see Fig. 23. Mark the two screw locations, two
interlocking ear locations and the two plug-in
connector locations. Drill the pilot holes for the
mounting screws. Provide for two holes on the
door panel for the interlocking ears and plug-in
connector holes.
c. Mount the Keyboard Display Module securing it
with the two extra screws provided in a bag
assembly with the Keyboard Display Module.
When mounting the Keyboard Display Module on a wall
or remote location, use the Remote Mounting Bracket,
part no. 203765.
a. Use the Remote Mounting Bracket as a template.
Mark the four screw locations and drill the pilot
holes. Mount the Remote Mounting Bracket by
securing the four M3.5 x 0.6 screws, see Fig. 12.
b. Mount the Keyboard Display Module by aligning
the two interlocking ears with the two mating slots
on the Remote Mounting Bracket.
c. Insert the two interlocking ears with the two
mating slots. Push on the lower corners of the
Keyboard Display Module to secure it to the
Remote Mounting Bracket.
d. Verify the Keyboard Display Module is firmly in
place.
Installing Plug-In Flame Signal Amplifier
Disconnect power supply before beginning installaion to
prevent electrical shock and equipment damage. More
than one disconnect may be involved, see Fig. 13.
Align the amplifier circuit board edge connector with the
keyed receptacle on the Relay Module. Verify the
amplifier nameplate faces away from the Relay Module.
Push in the amplifier until the circuit board is fully
inserted into the receptacle and then push the amplifier
toward the Relay Module retaining clasp.
Verify the amplifier is firmly in place.
Perform all required checkout tests.
Installing the Flame Detector
NOTE: Table 2 lists the flame detection systems available for
use with the Relay Module. Make sure the correct
combination of amplifier and flame detector(s) is used.
Proper flame detector installation is the basis of a safe and
reliable flame safeguard installation. Refer to the instructions
packed with the flame detector and the equipment
manufacturer instructions, see Fig. 14.
Keep the flame signal leadwires as short as possible from the
flame detector to the wiring subbase. Capacitance increases
with leadwire length, reducing the signal strength. The
maximum permissible leadwire length depends on the type of
flame detector, leadwire and conduit. The ultimate limiting
factor of flame detector leadwire length is the flame signal,
see Table 7.
7800 SERIES RM7830A, RM7850A RELAY MODULE
Fig. 12. Remote mounting of Keyboard Display Module.
Run/Test Switch Functions
The Run/Test Switch is located on the top side of the Relay
Module. The Run/Test Switch allows the burner sequence to
be altered as follows:
In Purge Drive To High Fire position, the Run/Test
Switch when placed in the TEST position, holds in
PURGE with the firing rate motor in the High Fire
position (RM7850A).
In the measured PURGE sequence, the Run/Test
Switch, when placed in the TEST position, causes the
PURGE timing to stop. The firing rate motor is in the
High Fire position.
In Purge Drive to Low Fire position, the Run/Test
Switch, when placed in the TEST position, holds the
burner sequence in PURGE with the firing rate motor in
the Low Fire position (RM7850A).
During the PILOT STAB., the Run/Test Switch, when
placed in the TEST position, will stop the timer, allowing
for pilot-turn-down test and other burner adjustments.
This activates a fifteen second flameout timer that
permits pilot flame adjustment without nuisance safety
shutdowns.
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65-0222