RM7897A1002, RM7897C1000
7800 SERIES
Relay Modules
INSTALLATION INSTRUCTIONS
APPLICATION
The RM7897A,C are microprocessor-based integrated burner
controls for automatically fired gas, oil, or combination fuel
single burner applications. The RM7897A,C system consist of
a relay module, subbase, amplifier, and purge card. Options
include keyboard display module (KDM), Personal Computer
Interface, Data ControlBus™ Module, remote display
mounting, Expanded Annunciator and Combustion System
Manager® Software.
Functions provided by the RM7897A,C include automatic
burner sequencing, flame supervision, system status
indication, system or self-diagnostics and troubleshooting.
The RM7897 adds a proof of closure input to the standard
primary control function of the RM7895/RM7896 product. It
adds a blinking fault code function to the POWER LED on
Alarm shutdown. It also adds programmable postpurge using
the S7800A1142 Keyboard Display Module (KDM). The
RM7897A1002 offers selectable pilot operation, intermittent
on terminal 8 or interrupted on terminal 21.
The RM7897C1000 offers interrupted pilot and delayed main
valve for 2-step firing (Low-High-Low) applications.
This document provides installation and static checkout
instructions. Other applicable publications are:
Publication
No.Product
63-2278Q7700 Network Interface Unit Product Data
65-0084Q7800A,B 22-Terminal Wiring Subbase
Product Data
65-0288S7800A1142 Keyboard Display Module
Product Data
65-0091S7810A Data ControlBus Module™ Product
Data
65-0095S7820 Remote Reset Module Product Data
65-0097221729C Dust Cover Installation
Instructions
65-0101S7830 Expanded Annunciator Product Data
Publication
No.Product
65-0102 ZM7850A Combustion System Manager™
Operating Instructions
65-0109R7824, R7847, R7848, R7849, R7851,
R7861, R7886 Flame Amplifiers for the
7800 Series Product Data
65-0131221818A Extension Cable Assembly
Product Data
65-02297800 SERIES Relay Modules Checkout and
Troubleshooting Product Data.
65-0092QS7800A ControlBus™ Module, Standard
65-0227QS7800B ControlBus™ Module, Multidrop
SPECIFICATIONS
Electrical Ratings (See Table 3):
Voltage and Frequency:
RM7897A,C: 120 Vac (+10/-15%), 50/60 Hz (± 10%).
Power Dissipation: 10W maximum.
Maximum Total Connected Load: 2000 VA.
Fusing Total Connected Load: 15A Fast Blow, type SC or
equivalent.
Environmental Ratings:
Ambient Temperature:
Operating: -40°F to 140°F (-40°C to +60°C).
Storage: -40°F to 150°F (-40°C to +66°C).
Humidity: 85% relative humidity continuous, noncondensing.
Vibration: 0.5G environment.
Approvals:
Underwriters Laboratories Inc. Listed: File No. MP268,
Guide No. MCCZ.
Canadian Standards Association Certified: Pending.
Factory Mutual Approved: Report No. Pending.
IRI Acceptable.
Federal Communications Commission: Part 15, Class B,
Emissions.
66-1151
Page 2
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
INSTALLATION
When Installing this Product…
1. Read these instructions carefully. Failure to follow them
could damage the product or cause a hazardous
condition.
2. Check the ratings given in the instructions and marked
on the product to make sure the product is suitable for
the application.
3. Installer must be a trained, experienced, flame
safeguard service technician.
4. After installation is complete, check out the product
operation as provided in these instructions.
WARNING
Fire or Explosion Hazard.
Can cause severe injury, death or property
damage.
Follow applicable safety requirements when installing
a control on a burner to prevent death or severe injury.
WARNING
Electrical Shock Hazard.
Can cause serious injury, death or equipment
damage.
Disconnect power supply before beginning installation.
More than one disconnect may be required.
IMPORTANT
1. Wiring connections for the relay modules are unique;
refer to Fig. 2 and 3 or the appropriate Specifications
for proper subbase wiring.
2. Wiring must comply with all applicable codes,
ordinances and regulations.
3. Wiring must comply with NEC Class 1 (Line Voltage)
wiring.
4. Loads connected to the RM7897A,C must not
exceed those listed on the RM7897A,C label or the
Specifications; see Table 1.
5. Limits and interlocks must be rated to simultaneously
carry and break current to the ignition transformer,
pilot valve, and main fuel valve(s).
6. All external timers must be listed or
component-recognized by authorities who have
proper jurisdiction.
7. 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).
8. Two flame detectors can be connected in parallel
with the exception of Flame Detectors C7015,
C7927,C7961 and C7952.
9. This equipment generates, uses and can radiate
radio frequency energy and, if not installed and used
in accordance with the instructions, can cause
interference with radio communications. It has been
tested and found to comply with the limits for a Class
B computing device 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 may cause
interference, in which case, the users, at their own
expense, may be required to take whatever
measures are required to correct this interference.
10. This digital apparatus does not exceed the Class B
limits for radio noise for digital apparatus set out in
the Radio Interference Regulations of the Canadian
Department of Communications.
Location
Humidity
Install the relay module where the relative humidity never
reaches the saturation point. The relay module is designed to
operate in a maximum 85% relative humidity continuous,
noncondensing, moisture environment. Condensing moisture
can cause a safety shutdown.
Vibration
Do not install the relay module where it can be subjected to
vibration in excess of 0.5G continuous maximum vibration.
Weather
The relay module is not designed to be weather tight. When
installed outdoors, protect the relay module in an approved
weather-tight enclosure.
Mounting Wiring Subbase
1. Mount the subbase in any position except horizontally
with the bifurcated contacts pointing down. The
standard vertical position is recommended. Any other
position decreases the maximum ambient temperature
rating.
2. Select a location on a wall, burner or electrical panel.
The Q7800 can be mounted directly in the control
cabinet. Be sure to allow adequate clearance for
service, installation, access or removal of the
RM7897A,C expanded annunciator, keyboard display
module, flame amplifier, flame amplifier signal voltage
probes, run/test switch, electrical signal voltage probes
and electrical field connections.
3. For surface mounting, use the back of the subbase as a
template to mark the four screw locations. Then drill the
pilot holes.
4. Securely mount the subbase using four no. 6 screws
(not provided).
66-11512
Page 3
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Wiring Subbase
WARNING
Electrical Shock Hazard.
Can cause severe injury, death or equipment
damage.
Disconnect the power supply before beginning
installation. More than one disconnect may be
required.
The internal block diagram of the RM7897A,C is shown in Fig.
RM7897A-INTERRUPTED PILOT.
RM7897C-DELAYED MAIN VALVE.
INDICATES FEEDBACK SENSING
TO RELAY STATUS FEEDBACK
AND LINE VOLT INPUTS
FIELD WIRING
INTERNAL WIRING
OPTIONAL KEYBOARD
DISPLAY MODULE
DDL
DDL
COMMUNICATIONS
M22727A
1
RS485
2
3
REMOTE
RESET
5
RUN/TEST
SWITCH
RESET
PUSHBUTTON
STATUS LEDs
LIMITS
PREIGNITION
INTERLOCK
CONFIGURATION
JUMPERS
CONTROLLER
6K1
3K1
SAFETY RELAY
CIRCUIT
6
20
1. For proper subbase wiring and sequence chart, refer to
Fig. 2 and 3.
2. For remote wiring of the Keyboard Display Module, refer
to the Specifications for the Keyboard Display Module
(65-0288), Network Interface Unit (63-2278), Data
ControlBus™ Module (65-0091) or Extension Cable
Assembly (65-0131).
3. Disconnect the power supply from the main disconnect
before beginning installation to prevent electrical shock
and equipment damage. More than one disconnect can
be required.
4. All wiring must comply with all applicable electrical
codes, ordinances and regulations. Wiring, where
required, must comply with NEC, Class 1 (Line Voltage)
wiring.
5. For recommended wire size and type, see Table 1.
6. For recommended grounding practices, see Table 2.
120 VAC,
50/60 HZ
L1
(HOT)
1
MICROCOMPUTER
RELAY
DRIVE
CIRCUIT
1K
LOCKOUT
INTERLOCK
(INCLUDING
AIRFLOW SWITCH)
L2
FLAME SIGNAL
2K
3K
4K
5K
6K
7K
POWER SUPPLY
1K1 2K1 5K1
7
2K2
7K16
PLUG-IN PURGE
TIMER CARD
PLUG-IN
TEST
FLAME
AMPLIFIER
RELAY
STATUS
FEEDBACK
AND LINE
VOLTAGE
INPUTS
CONTROL
POWER
10
4K1
8
9
21
4
3
TEST
JACK
F
G
22
IGNITION
PILOT
MAIN VALVE
BLOWER
ALARM
L2
2
3
Fig. 1. Internal block diagram of RM7897A,C (see Fig. 2 and 3 for detailed wiring instructions).
7. Recommended wire routing of leadwires:
a. Do not run high voltage ignition transformer wires
in the same conduit with the flame detector, Data
ControlBus Module™, or Remote Reset Module
wiring.
b. Do not route flame detector, Data ControlBus™
Module, or Remote Reset Module leadwires in
conduit with line voltage circuits.
c. Enclose flame detector leadwires without armor
cable in metal cable or conduit.
d. Follow directions in flame detector, Data
ControlBus™ Module, or Remote Reset Module
Instructions.
8. The KDM is powered from a low voltage, energy limited
source. It can be mounted outside of a control panel if it
is protected from mechanical damage.
NOTE: A 13 Vdc power supply must be used any time more
than one KDM is used.
366-1151
Page 4
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Q7800
LINE VOLTAGE ALARM
BURNER MOTOR
(BLOWER)
BURNER
CONTROLLER/LIMITS
RUNNING INTERLOCK
(INCLUDING
AIRFLOW SWITCH)
INTERMITTENT
PILOT/IGNITION
MAIN FUEL VALVE(S)
IGNITION
FLAME DETECTOR
3
G
L2
3
4
5
6
7
8
9
10
F
(L1)
12
13
14
15
16
17
18
19
20
21
22
FOR DIRECT SPARK IGNITION
(OIL OR GAS)
IGNITION
10
TRANSFORMER
8
MAIN VALVE
2
PREIGNITION
INTERLOCK
MASTER
SWITCH
L1
(HOT)
L2
L2
10-SECOND
INTERRUPTED
PILOT
1
INITIATE
(INITIAL
POWERUP
ONLY)
POWER
LED
DISPLAY
BURNER
OPERATING
CONTROLS
AND
INTERLOCKS
PREIGNITION INTERLOCK CLOSED
FLAME
SIGNAL
1
120 VAC, 50/60 HZ POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
DO NOT CONNECT ANY WIRES TO UNUSED TERMINALS.
2
STANDBY
LIMITS AND BURNER CONTROLLER CLOSED
SAFE START CHECKFLAME PROVING
00
POWER
5
TIMED
PREPURGE
POWER
PILOT
FLAME
MAIN
BURNER/BLOWER MOTOR
10
RUNNING INTERLOCKS CLOSED
PFEP
10 SEC.
00
(4 SEC. IF
JR1
INTERRUPTED PILOT
10
CLIPPED
POWER
PILOT
FLAME
MAIN
IGN.
20TO5
3
4
5
RUN
POWER
PILOT
FLAME
MAIN
ALARM
9
00
4
POSTPURGE
POWER
STANDBY
POWER
PII
SSC
M22728B
20
MFEP
POWER
PILOT
FLAME
MAIN
ALARMALARMALARM
5
8INTERMITTENT PILOT
8
21
21
MAIN VALVE
TO
6
L1
6
7TO
SEE FLAME DETECTOR SPECIFICATIONS FOR CORRECT WIRING.
PROGRAMMED ON SETUP USING S7800A1142 DISPLAY.
PURGE TIME DEPENDS ON WHICH ST7800 IS INSTALLED.
Fig. 2. Wiring subbase and sequence chart for RM7897A.
66-11514
Page 5
LINE VOLTAGE
ALARM
BURNER MOTOR
(BLOWER)
BURNER
CONTROLLER/LIMITS
RUNNING INTERLOCK
(INCLUDING
AIRFLOW SWITCH).
10 SEC. INTERRUPTED
PILOT/IGNITION
MAIN FUEL VALVE(S)
IGNITION
FLAME DETECTOR
4
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Q7800
G
L2
3
4
5
6
7
8
9
10
F
(L1)
12
13
14
15
16
17
18
19
20
21
22
FOR DIRECT SPARK IGNITION
(OIL OR GAS)
IGNITION
10
TRANSFORMER
8
9
MAIN VALVE
2
DELAYED
(2ND STAGE)
MAIN VALVE
MASTER
SWITCH
L1
(HOT)
L2
PREIGNITION
INTERLOCK
1
L2
INITIATE
(INITIAL
POWERUP
ONLY)
POWER
LED
DISPLAY
BURNER
OPERATING
CONTROLS
AND
INTERLOCKS
FLAME
SIGNAL
1
120 VAC, 50/60 HZ POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
DO NOT CONNECT ANY WIRES TO UNUSED TERMINALS.
2
LIMITS AND BURNER CONTROLLER CLOSED
PREIGNITION INTERLOCK CLOSED
000010
TIMED
STANDBY
POWER
PREPURGE
SAFE START CHECK
PFEP
10 SEC.
5
(4 SEC. IF
CLIPPED
JR1
POWER
PILOT
FLAME
MAIN
POWER
PILOT
FLAME
MAIN
BURNER/BLOWER MOTOR
10
IGNITION
INTERRUPT/PILOT
RUNNING INTERLOCK
3
4
5
RUN
POWER
PILOT
FLAME
MAIN
ALARM
6
9
00
21
3
POSTPURGE
POWER
STANDBY
POWER
PII
SSC
M22729A
20
MFEP
POWER
PILOT
FLAME
MAIN
ALARMALARMALARM
5
8
MAIN VALVE
DELAYED MAIN VALVE
TO
L1
67
TO
20TO5
FLAME PROVING
PROGRAMMABLE POST PURGE TIMING USING S7800A1142 KDM.
SEE FLAME DETECTOR SPECIFICATIONS FOR CORRECT WIRING.
PURGE TIME DEPENDS ON WHICH ST7800 IS INSTALLED.
Fig. 3. Wiring subbase and sequence chart for RM7897C.
566-1151
Page 6
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Table 1. Recommended Wire Sizes and Part Numbers.
ApplicationRecommended Wire SizeRecommended Part Numbers
Line voltage terminals.14, 16 or 18 AWG copper conductor, 600 volt insulation,
TTW60C, THW75C, THHN90C.
moisture-resistant wire.
Keyboard Display Module22 AWG two-wire twisted pair with ground, or five-wire. Belden 8723 shielded cable or equivalent.
a
Data ControlBus™ Module
22 AWG two-wire twisted pair with ground, or five-wire. Belden 8723 shielded cable or equivalent.
13 Vdc full-wave rectified
transformer power input.
a
The KDM, Data ControlBus™ Module (for remote mounting or communications) or Communication Interface ControlBus™
22 AWG two-wire twisted pair with ground.Belden 8723 shielded cable or equivalent.
18 AWG wire insulated for voltages and temperatures
TTW60C, THW75C, THHN90C.
for given application.
Module must be wired in daisy chain configuration, 1(a)-1(a), 2(b)-2(b), 3(c)-3(c). The order of interconnection of all the devices
listed above is not important. Be aware that modules on the closest and farthest end of the daisy chain configuration string
require a 120 ohm (1/4 watt minimum) resistor termination across terminals 1 and 2 of the electrical connectors for connections
over 100 feet (31 meters).
Table 2. Recommended Grounding Practices.
Ground TypeRecommended Practice
Earth ground (subbase and relay
module).
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
15A, type SC,. fast blow 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 is required, 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.
Signal ground (Keyboard Display
Module, Data ControlBus™ Module,
Use the shield of the signal wire to ground the device to the signal ground terminal 3(c) of
each device. Connect the shield at both ends of the daisy chain to earth ground.
Communications Interface
ControlBus™ Module.
9. Maximum wire lengths:
a. RM7897A,C leadwires: The maximum leadwire
length is 300 feet to terminal inputs (Control,
10. Be sure loads do not exceed the terminal ratings. Refer
to the label on the RM7897A,C or to the terminal ratings
in Table 3.
Running/Lockout Interlock).
b. Flame Detector leadwires: The maximum flame
sensor leadwire length is limited by the flame signal
strength.
c. Remote Reset leadwires: The maximum length of
wire is 1000 feet (305 meters) to a Remote Reset
push button.
d. Data ControlBus Module™: The maximum Data
ControlBus™ Module cable length depends on the
number of system modules connected, the noise
conditions and the cable used. The maximum length
of all Data ControlBus™ Module interconnecting
wire is 4000 feet (1219 meters).
Final Wiring Check
1. Check the power supply circuit. The voltage and
frequency tolerance must match those of the
RM7897A,C. A separate power supply circuit can be
required for the RM7897A,C. Add the required
disconnect means and overload protection.
2. Check all wiring circuits and complete Static Checkout
in Table 6 before installing the RM7897A,C on the
subbase.
3. Install all electrical connectors.
4. Restore power to the panel.
66-11516
Page 7
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
STATIC CHECKOUT
After checking all wiring, perform this checkout before
external controllers, limits, interlocks, actuators, valves,
transformers, motors and other devices are operating
properly.
installing the RM7897A,C on the subbase. These tests verify
the Q7800 Wiring Subbase is wired correctly, and the
5Line Voltage Supply (L1)120 Vac (+10/-15%), 50 or 60 Hz
(±10%).
b
6Burner Controller and Limits120 Vac, 1 mA.
7Lockout Interlock120 Vac, 8A run, 43A inrush.
8Pilot Valve/Ignition
9Main Fuel Valve
10Ignition
120 Vac
120 Vac
120 Vac
c
c
c
F(11)Flame Sensor60 to 220 Vac, current limited.
12 to 19——
20PreIgnition Interlock120 Vac, 1 mA.
21Interrupted Pilot (RM7897A)120 Vac
212nd Stage Main Valve (RM7897C)
120 Vac
c
22Shutter120 Vac, 0.5A
a
See Table 2.
b
2000 VA maximum load connected to RM7897A,C Assembly.
c
See Tables 4 and 5.
Table 4. Combinations for Terminals 8, 9, 10 and 21.
Combination NumberPilot Fuel 8Main 9Ignition 10
Delayed Main Valve 21
(RM7897A Only)
Delayed Main Valve 21
(RM7897C Only)
1CFNo LoadCNo Load
2BFNo LoadBNo Load
3
a
F
FAFNo Load
4FFAFNo Load
5
a
F
FAF F
6DFADNo Load
7
a
D
DA DD
8DDADNo Load
9
a
RM7897C only, jumper terminals 8 to 9.
a
D
No LoadA DD
766-1151
Page 8
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Table 5. Composition of each Combination.
ABCDF
4.5A ignition50 VA Pilot Duty plus
4.5A ignition.
180 VA Ignition plus
motor valves with:
660 VA inrush,
360 VA open,
240 VA hold.
WARNING
Fire or Explosion Hazard.
Can cause property damage, severe injury
or death.
Close all manual fuel shutoff valve(s) before starting
these tests.
Use extreme care while testing the system. Line
voltage is present on most terminal connections when
power is on.
Ensure proper selection of configuration jumpers before
starting the burner operation.
2A Pilot Duty65 VA Pilot Duty plus
motor valves with:
3850 VA inrush,
700 VA open,
250 VA hold.
6. If there is no voltage or the operation is abnormal, check
the circuits and external devices as described in the last
column.
7. Check all wiring for correct connections, tight terminal
screws, correct wire, and proper wiring techniques.
Replace all damaged or incorrectly sized wires.
8. Replace faulty controllers, limits, interlocks, actuators,
valves, transformers, motors and other devices, as
required.
9. Make sure normal operation is obtained for each
required test before continuing the checkout.
10. After completing each test, be sure to open the master
power switch and remove the test jumper(s) before
proceeding to the next test.
CAUTION
Electrical Hazard.
Can cause equipment damage or failure.
Do not perform a dielectric test with the relay module
installed. Internal surge protectors can break down,
allowing relay module to fail the dielectric test and
destroy the internal lightning and high current
protection.
1. Open the master switch before installing or removing a
jumper on the subbase.
2. Before continuing to the next test, be sure to remove the
test jumper(s) used in the previous test.
3. Replace all limits and interlocks that are not operating
properly. Do not bypass limits and interlocks.
Equipment Recommended
1. Voltmeter (1M ohm/volt minimum sensitivity) set on the
0 to 300 Vac scale.
2. Two jumper wires, no. 14 wire, insulated, 12 in.
(304.8 mm) long with insulated alligator clips at both
ends.
General Instructions
1. Perform all applicable tests listed in Static Checkout,
Table 6, in the order listed.
2. Make sure all manual fuel shutoff valve(s) are closed.
3. For each test, open the master switch and install the
jumper wire(s) between the subbase wiring terminals
listed in the Test Jumpers column.
4. Close the master switch before observing operation.
5. Read the voltage between the subbase wiring terminals
listed in the Voltmeter column.
WARNING
Explosion hazard.
Can cause serious injury or death.
Be sure all manual fuel shutoff valves are closed.
Mounting RM7897A,C Relay Module
1. Mount the RM7897A,C vertically on the Q7800
Subbase or mount horizontally with the knife blade
terminals pointing down. When mounted on the
Q7800A, the RM7897A,C must be in an electrical
enclosure.
2. When mounting in an electrical enclosure, provide
adequate clearance for servicing, installation and
removal of the RM7897A,C, KDM, flame amplifier, flame
amplifier signal voltage probes, electrical signal voltage
probes and electrical connections.
e. Allow an optional three-inch (76 mm) minimum on
both sides of the RM7897A,C for electrical signal
voltage probes.
3. Make sure no subbase wiring is projecting beyond the
terminal blocks. Tuck in wiring against the back of the
subbase so it does not interfere with the knife blade
terminals or bifurcated contacts.
IMPORTANT
The RM7897A,C, must be installed with a plug-in
motion rather than a hinge action.
4. Mount the RM7897A,C by aligning the four L-shaped
corner guides and knife blade terminals with the
bifurcated contacts on the wiring subbase and securely
tightening the two screws without deforming the plastic.
66-11518
Page 9
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Table 6. Static Checkout.
Test
Number
1AllNone5-L2Line voltage at terminal 5.1. Master switch.
2AllNone6-L2Line voltage at terminal 6.1. Limits.
3All4-57-L21. Burner motor (fan or blower)
4All5-10—1. Ignition spark (if ignition
5All20-L2Line voltage at Terminal 20Preignition Interlocks.
6All5-8—1. Ignition spark (if ignition
Relay Module
Model
Test
Jumpers VoltmeterNormal Operation
starts.
2. Line voltage at terminal 7
within 10 seconds.
transformer is connected to
terminal 10).
transformer is connected to
terminal 8).
2. Automatic pilot valve opens
(if connected to terminal
8).
If Operation is Abnormal,
Check Items Listed Below
2. Power connected to master switch.
3. Overload protection (fuse, circuit breaker,
etc.) has not opened power line.
2. Burner controller.
1. Burner motor circuit.
a. Manual switch of burner motor.
b. Burner motor power supply, overload
protection and starter.
c. Burner motor.
1. Watch for spark or listen for buzz.
a. Ignition electrodes are clean.
b. Ignition transformer is okay.
1. Watch for spark or listen for buzz.
2. Listen for click or feel head of valve for
activation.
a. Actuator if used.
b. Pilot valve.
NOTE: Refer to wiring diagram
7All5-9—Automatic fuel valve(s) open(s). If
using direct spark ignition, check
first stage fuel valve(s) instead of
pilot valve.
8aRM7897A5-21—1. Ignition spark (if ignition
NOTE: Refer to wiring diagram
8bRM7897C5-21—Automatic second stage main fuel
valve(s) open(s).
9All5-3—Alarm (if used) turns on.1. Alarm.
FinalAll
of system being tested.
connected to terminal
21).
2. Automated Pilot Valve
opens (if connected to
terminal 21).
of system being tested.
Same as test 6. If using direct spark
ignition, check first stage fuel valve(s)
instead of pilot valve.
1. Watch for spark or listen for buzz.
2. Listen for click or feel head of valve for
activation.
a. Actuator if used.
b. Pilot valve.
1. Listen for and observe operation of
second stage main fuel valve(s) and
actuator(s).
2. Valve(s) and actuator(s).
CAUTION
Equipment Damage Hazard.
Can cause equipment damage.
After completing these tests, open master switch and remove all test jumpers from subbase
terminals. Also remove bypass jumpers, if used, from low fuel pressure limits.
Mounting Other System Components (Fig. 4)
Refer to the applicable specifications for mounting other
system components.
Setup of Post Purge
An S7800A1142, Keyboard Display Module (KDM), is
required for the setup of the RM7897 Post Purge Timing, and
must be purchased separately.
When the RM7897A,C is installed and powered, “STANDBY”
will be shown on the first line of the display (Fig. 5).
966-1151
Page 10
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
WIRING
SUBBASE
RUN/TEST (C,D ONLY)
SWITCH
RELAY
MODULE
CONFIGURATION
JUMPERS
PURGE
TIMER
SEQUENCE
STATUS
LED PANEL
POWER
PILOT
FLAME
MAIN
ALARM
RESET
KEYBOARD
DISPLAY
MODULE
RESET
BUTTON
HONEYWELL
CAPTIVE
MOUNTING
SCREW
BURNER CONTROL
EDIT:
_
BACK
+
- ENTER -
Fig. 4. RM7897A,C Relay Module, exploded view.
STANDBY
Setup
BACK
Edit:
-+
ENTER
M22662B
Fig. 5. Setup Needed screen.
1. Scroll down until “Setup” is displayed in the second line.
2. Enter the setup sub-routine by pressing the far right
arrow key on the display.
FLAME
AMPLIFIER
M22827
STANDBY
SU
± BC Password: 00
BACK
Edit:
-+
ENTER
M22663B
Fig. 6. Entering the setup sub-routine.
The second line reads “BC Password”.
3. Use the up/down arrows to enter the first number, 7.
4. Use the far right arrow key to shift over one space.
5. Use the up/down arrows to enter the second number, 8.
6. Press Enter (left/right arrow simultaneously).
66-115110
Page 11
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
=Select
=Restart
BACK
Edit:
-+
ENTER
M22764B
Fig. 7. Select/Restart screen.
7. Press down arrow to select.
8. “Getting Data” will be momentarily displayed, followed
by the screen shown in Fig. 8.
SETUP:Postpurge
SU
±PostTime: 00:30
BACK
Edit:
-+
ENTER
M22668
Fig. 8. Setting Post Purge time.
This screen allows for setting up the Postpurge for the
RM7897A,C. This will be the time that the Combustion Fan
(terminal 4) will remain energized after the call for heat has
ended (terminal 6).
9. Use the up arrow to increase the postpurge time.
Time increases:
0 to 60 seconds in 1 second intervals.
60 to 600 seconds in 10 second intervals.
CONFIRM: Postpurge
SC
±PostTime: 00:30 ?
BACK
Edit:
-+
ENTER
M22674A
Fig. 10. Confirm Postpurge time.
1. Press Enter.
=Confirm correct
=Incorrect
BACK
Edit:
-+
ENTER
M22671B
Fig. 11. Confirm correct/incorrect screen.
2. Press the down arrow to confirm the correct postpurge
time. “Getting Data” will be displayed until the screen in
Fig. 12 appears.
SETUP DONE: Press
Reset for 5 sec . . .
BACK
Edit:
-+
ENTER
M22676B
10 to 60 minutes in 1 minute intervals.
10. Press Enter (Left/Right arrow keys simultaneously)
when the correct postpurge time is displayed.
=Save changes
=Restart
BACK
Edit:
-+
ENTER
M22665B
Fig. 9. Save Changes screen.
11. Use the down arrow to save changes. “Getting Data” is
displayed momentarily.
The following steps are used to confirm your selection.
Fig. 12. Setup Done screen.
3. Go to the RM7897 and press and hold the reset button
for five seconds to program the postpurge time into the
relay module.
The Release Reset screen will appear on the KDM.
SETUP DONE:
... release Reset
BACK
Edit:
-+
ENTER
M22765B
Fig. 13. Release Reset screen.
Changing the postpurge time feature is still possible. With the
RM7897 in Standby, scrolling to the Setup line and entering
with the password allows the settings to be changed.
1166-1151
Page 12
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Once the system is in operation, the settings of the postpurge
time can be viewed under Diagnostics, using your S7800
Keyboard Display Module.
PRINCIPAL TECHNICAL FEATURES
The RM7897 provides all customary flame safeguard
functions as well as significant advancements in safety,
annunciation, and system diagnostics.
Safety Shutdown (Lockout) Occurs if:
1. INITIATE PERIOD
a. Purge card is not installed or removed.
b. Purge card is bad.
c. Configuration jumpers have been changed (after
200 hours)—Fault Code 110.
d. AC line power errors occurred, see Operation.
e. Four minute INITIATE period has been exceeded.
2. STANDBY PERIOD
a. Airflow lockout feature is enabled and the airflow
switch does not close after ten seconds or within the
specified purge card timing.
b. Flame signal is detected after 240 seconds.
c. Ignition/pilot valve terminal is energized.
d. Main valve terminal is energized.
e. Delayed main valve terminal is energized
(RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
i. PreIgnition Interlock open.
3. PREPURGE PERIOD
a. Airflow lockout feature is enabled and the airflow
switch opens.
b. Ignition/pilot valve terminal is energized.
c. Main valve terminal is energized.
d. Delayed main valve terminal is energized
(RM7897C).
e. Internal system fault occurred.
f. Purge card is removed.
g. Purge card is bad.
h. Flame signal is detected for 30 seconds.
i. Preignition interlocks open during standby.
4. PILOT FLAME ESTABLISHING PERIOD (PFEP)
a. Airflow lockout feature is enabled and the airflow
switch opens.
b. No flame signal at end of PFEP.
c. Ignition/pilot valve/intermittent pilot valve terminal is
not energized.
d. Main valve terminal is energized (RM7897A).
e. Delayed (second stage) main valve terminal is
energized (RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
5. MAIN FLAME ESTABLISHING PERIOD (MFEP)
(RM7897A, terminal 21; RM7897C, terminal 8)
a. Airflow lockout feature is enabled and the airflow
switch opens.
b. Ignition terminal is energized.
c. Ignition/pilot valve terminal is not energized.
d. Main valve terminal is not energized.
e. Delayed main valve terminal is energized.
f. Loss of flame signal.
g. Internal system fault occurred.
h. Purge card is removed.
i. Purge card is bad.
6. RUN PERIOD
a. No flame present (JR2 removed).
b. Airflow lockout feature is enabled and the airflow
switch opens.
c. Interrupted pilot valve terminal is energized
(RM7897A, terminal 21; RM7897C, terminal 8).
d. Main valve terminal is not energized.
e. Delayed main valve terminal is not energized
(RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
i. Ignition terminal is energized.
OPERATION
Sequence of Operation
The RM7897A,C has the operating sequences listed below;
see Fig. 2 and 3. The RM7897A,C LED provide positive visual
indication of the program sequence: POWER, PILOT, FLAME,
MAIN and ALARM.
Initiate
The RM7897A,C Relay Module enters the INITIATE sequence
when the relay module is powered. The RM7897A,C can also
enter 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 not met, a hold
condition is initiated and displayed on the optional KDM for at
least five seconds; when met, the INITIATE sequence
restarts. If the condition is not corrected and the hold condition
exists for four minutes, the RM7897A,C locks out. Causes for
hold conditions in the INITIATE sequence:
1. AC line dropout detection.
2. AC line noise that can prevent a sufficient reading of the
line voltage inputs.
3. Low line voltage brownouts.
The INITIATE sequence also delays the burner motor starter
from being energized and de-energized from an intermittent
AC line input or control input.
Standby
The RM7897A,C is ready to start an operating sequence
when the operating control input determines a call for heat is
present. The burner switch, limits, operating limit control and
all microcomputer-monitored circuits must be in the correct
state for the relay module to continue into the PREPURGE
sequence.
Normal Start-Up Prepurge
The RM7897A,C Relay Module provides PREPURGE timing,
selectable with ST7800 Purge Timer cards, from two seconds
to thirty minutes with power applied and the operating control
indicating a call for heat.
66-115112
Page 13
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
1. The Airflow Interlock, burner switch, Run/Test switch
and all microcomputer-monitored circuits must also be
in the correct operating state.
2. The motor output, terminal 4, is powered to start the
PREPURGE sequence.
3. The Airflow Interlock input closes ten seconds into
PREPURGE or within the specified purge card timing;
otherwise, a recycle to the beginning of PREPURGE or
lockout occurs, depending on how the Airflow Switch
selectable jumper (JR3) is configured.
Ignition Trials
1. Pilot Flame Establishing Period (PFEP):
a. When the PFEP begins:
(1) The pilot valve and ignition transformer,
terminals 8 and 10 (also terminal 21, RM7897A),
are energized. The RM7897A has an intermittent
pilot valve, terminal 8, and interrupted pilot valve
on terminal 21. The RM7897C has an
interrupted pilot valve, terminal 8.
(2) Flame must be proven by the end of the ten
second PFEP (four seconds if Configuration
Jumper JR1 is clipped) to allow the sequence to
continue. If a flame is not proven by the end of
PFEP, a safety shutdown occurs.
(3) the Pre-Ignition Interlock is ignored throughout
the Trial for Ignition State.
2. Main Flame Establishing Period (MFEP):
a. After PFEP, and with the presence of flame,
the main fuel valve, terminal 9, is powered. If a
flameout occurs, the relay module locks out or
recycles (depending on status of jumper JR2) within
0.8 or 3 seconds, depending on the Flame Failure
Response Time (FFRT) of the amplifier.
b. The RM7897A (terminal 21) and RM7897C
(terminal 8) have a ten second MFEP. After the
Ignition Trials, the interrupted pilot valve, terminal 8
or 21, is de-energized. If a flameout occurs, the
relay module locks out or recycles (depending on
status of jumper JR2) within 0.8 or 3 seconds,
depending on the Flame Failure Response Time
(FFRT) of the amplifier.
Run
1. The RM7897C has a delayed main valve that is
energized once the RUN period is entered.
2. The relay module is now in RUN and remains in RUN
until the controller input, terminal 6, opens, indicating
that the demand is satisfied or a limit has opened.
Post Purge
After demand is satisfied or a limit opens, de-energizing
terminal 6, the Ignition/Pilot valve, main valve and delayed
main valve, terminals 8, 9 and 21, are de-energized. The
blower motor, terminal 4, remains powered during the
specified programmed time. The Pre-Ignition Interlock closes
within the first five seconds of Post Purge.
Run/Test Switch
The Run/Test Switch is located on the top side of the relay
module, see Fig. 12. The Run/Test Switch allows the burner
sequence to be altered as follows:
1. In the measured PREPURGE sequence, the Run/Test
Switch, placed in the TEST position, causes the
PREPURGE timing to stop.
2. In the Pilot Flame Establishing Period, the Run/Test
Switch, placed in the TEST position, stops the timer
during the first eight seconds of a ten-second PFEP
selection or during the first three seconds of a
four-second PFEP selection. It also allows 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. The Run/Test Switch is ignored during
PFEP for the C relay module if terminals
8 and 9 or 9 and 21 are jumpered.
IMPORTANT
When the relay module is switched to the TEST
mode, it stops and holds at the next Run/Test Switch
point in the operating sequence. Make sure that the
Run/Test Switch is in the RUN position before
leaving the installation.
RUN/TEST SWITCH
SEQUENCE
STATUS
LEDs
RESET
PUSHBUTTON
FLAME
SIMULATOR INPUT
FLAME CURRENT
TEST JACKS
CAPTIVE
MOUNTING
SCREW
PLUG-IN
PURGE
CARD
DUST
COVER
RELAY
MODULE
FLAME
AMPLIFIER
M7552A
Fig. 14. Sequence Status LEDs.
SETTINGS AND ADJUSTMENTS
Selectable Site-Configurable Jumpers
The relay module has three site-configurable jumper options,
see Fig. 13 and Table 7. If necessary, clip the site-configurable
jumpers with side cutters and remove the resistors from the
relay module.
SERVICE NOTE: Clipping and removing a site-configurable
jumper enhances the level of safety.
IMPORTANT
Clipping and removing a jumper after 200 hours of
operation causes a nonresettable Fault 110. The
relay module must then be replaced.
1366-1151
Page 14
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
SELECTABLE CONFIGURATION JUMPERS
RUN/TEST SWITCH
(EC7895C; RM7895C,D; RM7896C,D)
M7553A
Fig. 15. Selectable site-configurable jumpers.
Table 7. Site-configurable jumper options.
Jumper
NumberDescriptionIntactClipped
JR1Pilot Flame Establishing
Period (PFEP)
10
seconds4 seconds
JR2Flame Failure ActionRecycle Lockout
JR3Airflow Switch (ILK) FailureRecycle Lockout
TROUBLESHOOTING
The POWER LED provides fault identification when the Relay
Module locks out on an alarm. Fault identification is a series of
fast- and slow-blinking LED lights. The fast blinks identify the
tens portion of the fault code (three fast blinks is 30), while the
slow blinks identify the units portion of the fault code (two slow
blinks is 2). Three fast blinks followed by two slow blinks
would be fault code 32. This identifies a running interlock on
during STANDBY. (See Table 8 for Blinking Fault Code List.)
The LED code repeats as long as the fault exists. To clear the
fault, press the RESET button.
Table 8. Blinking Fault Codes and Recommended Troubleshooting.
Low AC Line detected.1. Check the relay module and display module connections.
2. Reset and sequence the Relay Module.
3. Check the 7800 power supply and make sure that frequency and voltage meet
Excessive noise or
device running on slow,
specifications.
4. Check the backup power supply, as appropriate.
fast, or AC line dropout
detected.
Code 2-1
*Unexpected
Flame Signal*
Flame sensed when no
flame is expected during
STANDBY or PURGE.
1. Check that flame is not present in the combustion chamber; correct any errors.
2. Make sure that the flame amplifier and flame detector are compatible.
3. Check the wiring and correct any errors.
4. Remove the flame amplifier and inspect its connections. Reseat the amplifier.
5. Reset and sequence the relay module.
6. If the code reappears, replace the flame amplifier and/or the flame detector.
7. If the fault persists, replace the relay module.
Code 2-2
*Flame Signal
Absent*
No-flame time present
at the end of the PIlot
Flame Establishing
Period; lost during the
Main Flame Establishing
Period or during RUN.
1. Measure the flame signal. If one exists, verify that it meets specifications.
2. Make sure that the flame amplifier and flame detector are compatible.
3. Inspect the main fuel valve(s) and valve connection(s).
4. Verify that the fuel pressure is sufficient to supply fuel to the combustion
chamber. Inspect the connections to the fuel pressure switches. Make sure
they are functioning properly.
5. Inspect the Airflow Switch and make sure that it is functioning properly.
6. Check the flame detector sighting position; reset and recycle. Measure the
flame signal strength. Verify that it meets specifications. If not, refer to the
flame detector and/or flame amplifier checkout procedures in the installation
instructions.
7. Replace the flame amplifier and/or the flame detector, if necessary.
8. If the fault persists, replace the relay module.
66-115114
Page 15
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Table 8. Blinking Fault Codes and Recommended Troubleshooting. (Continued)
Running or Lockout
Interlock fault during
Prepurge.
Lockout Interlock
powered at improper
point in sequence or On
in Standby.
VPS (Valve Proving
Switch) in wrong state
during VPS Test.
No purge card or the
purge card timing has
changed from the
original configuration.
Pilot (ignition) valve
terminal, main valve,
ignition or Main Valve 2
was on when it should
be off.
1. Make sure the flame detector and flame amplifier are compatible.
2. Remove the flame amplifier and inspect its connections. Reset the flame
amplifier.
3. Reset and sequence the relay module.
4. Check the flame detector sighting position; reset and recycle. Measure flame
strength. Verify that it meets specifications. If not, refer to the flame detector
and/or flame amplifier checkout procedures in the installation instructions.
5. If the code reappears, replace the flame amplifier and/or the flame detector.
6. If the fault persists, replace the relay module.
1. Check wiring; correct any errors.
2. Inspect the fan; make sure there is no air intake blockage and that it is supply-
ing air.
3. Make sure the Lockout Interlock switches are functioning properly and the
contacts are free from contaminants.
4. Reset and sequence the relay module to Prepurge (place the TEST/RUN
Switch in the TEST position, if available). Measure the voltage between
terminal 7 and G (ground); 120 Vac should be present. Switch TEST/RUN
back to RUN.
5. If steps 1 through 4 are correct and the fault persists, replace the relay module.
1. Check wiring to make sure that the Lockout Interlocks are connected properly
between terminals 6 and 7. Correct any errors.
2. Reset and sequence the relay module.
3. If the fault persists, measure the voltage between terminal 6 and G (ground),
then between terminal 7 and G. If there is 120 Vac at terminal 6 when the
controller is off, the controller switch may be bad or is jumpered.
4. If steps 1 through 3 are correct and there is 120 Vac at terminal 7 when the
controller is closed and the fault persists, check for a welded or jumpered
Running Interlock or Airflow Switch. Correct any errors.
5. If steps 1 through 4 are correct and the fault persists, replace the relay module.
1. Check wiring, making sure upstream valve is connected to terminal 9 and
downstream valve is connected to terminal 17.
2. Conduct Valve Seat leakage test using a manometer.
3. Reset and sequence the relay module; if fault repeats, test VPS (connected to
terminal 16) is functioning properly; replace if necessary.
4. Reset and sequence the relay module.
5. If fault persists, replace the relay module.
1. Make sure the purge card is seated properly.
2. Inspect the purge card and the connector on the relay module for any damage
or contaminants.
3. Reset and sequence the relay module.
4. If the fault code reappears, replace the purge card.
5. Reset and sequence the relay module.
6. If the fault code persists, replace the relay module.
WARNING
Electrical Shock Hazard; Fire or Explosion Hazard.
Can cause severe injury, death or property damage.
Remove system power and turn off power supply.
Code 4-3
*Flame
Amplifier
Problem*
Flame not sensed, or
sensed when it should
be on or off.
1. Remove system power and turn off fuel supply.
2. Check wiring; correct any errors.
3. inspect Pilot Fuel Valve(s), both places, and connections.
4. Reset and sequence the relay module.
5. If the fault persists, replace the relay module.
1. Check wiring; correct any errors.
2. Make sure the flame amplifier and flame detector are compatible.
3. Remove the flame amplifier and inspect the connections. Reseat the amplifier.
4. Reset and sequence the relay module.
5. If the code reappears, replace the flame amplifier and/or the flame detector.
6. If the fault persists, replace the relay module.
1566-1151
Page 16
RM7897A1002, RM7897C1000 7800 SERIES RELAY MODULES
Table 8. Blinking Fault Codes and Recommended Troubleshooting. (Continued)
The configuration
jumpers differ from the
sample taken at startup.
Preignition Interlock
fault.
1. Inspect the jumper connections. Make sure the clipped jumpers were
completely removed.
2. Reset and sequence the relay module.
3. If the fault persists, replace the relay module.
1. Check wiring and correct any errors.
2. Check Preignition Interlock switches to assure proper functioning.
3. Check fuel valve operation.
4. Reset and sequence the relay module; monitor the Preignition Interlock status.
5. If the fault persists, replace the relay module.
Code 5-2
*High Fire Sw.
or Low Fire
Sw.*
Either High Fire Switch
or Low Fire Switch
failure.
1. Check wiring and correct any errors.
2. Reset and sequence the relay module.
3. Use manual motor potentiometer to drive the motor open and closed. Verify at
motor switch that the end switches are operating properly. Use RUN/TEST
switch if manual potentiometer is not available.
4. Reset and sequence the relay module.
5. If the fault persists, replace the relay module.
Code 5-3
*Man-Open
Sw.; Start Sw.
or Control On*
Man-Open Switch, Start
Switch or Control On in
the wrong operational
state.
1. Check wiring and correct any errors.
2. Make sure that the Manual Open Valve Switch, Start Switch and Control are
operating properly.
3. Stat Switch held “On” too long.
4. Reset and sequence the relay module.
5. Reset and sequence the relay module. If the fault persists, replace the relay
module (RM7838A1014; RM7838B1013 or RM7838C1004 only).
Code 6-1
*Internal Faults*
Relay Module self-test
failure.
1. Reset and sequence the relay module.
2. If fault reappears, remove power from the device, reapply power, then reset
and sequence the relay module.
3. If the fault persists, replace the relay module.
Code 6-2
*Internal Faults*
Relay Module Self-Test
failure.
1. Reset and sequence the relay module.
2. If fault reappears, remove power from the device, reapply power, then reset
and sequence the relay module.
3. If fault does not repeat on the next cycle, check for electrical noise being
copied into the relay module through the external loads or possibly an
electrical grounding issue.
4. If the fault persists, replace the relay module.
Code 6-3
*Device
Specific*
Fault with special OEM
input circuits.
1. Check wiring and operation of special OEM inputs.
2. Reset and sequence the relay module.
3. If fault reappears, remove power from the device, reapply power, then reset
and sequence the relay module.
4. If the fault does not repeat on the next cycle, check for electrical noise being
copied into the relay module through the external loads or possibly an
electrical grounding issue.
5. If the fault persists, replace the relay module.
Code 6-4
Unused at this time.—
*Accessory
Fault*
Code 7-7
Unused at this time.—
*Unused*
Automation and Control Solutions
Honeywell International Inc.Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North35 Dynamic Drive
Golden Valley, MN 55422Scarborough, Ontario M1V 4Z9