Azbil FRS100 User manual

FRS100
Multiburner Controller
User's Manual
No. CP-SP-1373E
Thank you for purchasing the FRS100
Multiburner Controller.
This manual contains information for
ensuring the correct use of the FRS100.
It also provides necessary information
for installation, maintenance, and trou-
bleshooting.
This manual should be read by those
who design and maintain equipment
that uses the FRS100. Be sure to keep
this manual nearby for handy reference.

NOTICE
© 2014 Azbil Corporation All Rights Reserved.
Be sure that the user receives this manual before the product is used.
Copying or duplicating this user’s manual in part or in whole is forbid-
den. The information and specifications in this manual are subject to
change without notice.
Considerable effort has been made to ensure that this manual is free
from inaccuracies and omissions. If you should find an error or omis-
sion, please contact Azbil Corporation.
In no event is Azbil Corporation liable to anyone for any indirect, special
or consequential damages as a result of using this product.

■About Icons
The safety precautions described in this manual are indicated by various icons.
Please be sure you read and understand the icons and their meanings described
below before reading the rest of the manual.
Safety precautions are intended to ensure the safe and correct use of this prod-
uct, to prevent injury to the operator and others, and to prevent damage to proper-
ty. Be sure to observe these safety precautions.
■Examples
i
Use caution when handling the product.
The indicated action is prohibited.
Be sure to follow the indicated instructions.
SAFETY PRECAUTIONS
WARNING Warnings are indicated when mishandling this
product might result in death or serious injury.
CAUTION Cautions are indicated when mishandling this product might result in minor injury to the user, or
only physical damage to the product.

ii
WARNING
Use this device for batch operation of the burner (at least one start and
stop in a 24-hour period). Do not use for continuous burner operation
(nonstop combustion for 24 h or longer).
This device does not have the prepurge and ignition sequencing func-
tions required for burner ignition. Use this device as part of a system
whose design gives careful consideration to the prepurge timer and
sequence timing, following established safety guidelines.
Wire terminals 1 and 2 so that they receive power continuously when-
ever the power switch is turned on. This is absolutely necessary to
ensure operation of the self-check circuits at startup.
Therefore, do not wire a thermostat between the power switch and ter-
minal 1 or 2. Doing so might cause a serious combustion equipment
accident.
Connect loads (ignition transformer, solenoid valve, etc.) directly to the
output terminals of this device. If they are not directly connected, com-
bustion safety cannot be ensured.
Do not allow the pilot or main burner "Safety Time" (ignition trial time)
to exceed the specifications of the burner or equipment manufacturer.
If they do, fuel may accumulate in the combustion chamber and form
an explosive air-fuel mixture, resulting in a serious explosion hazard.
Before removing, mounting, or wiring the FRS100, be sure to turn off
the power to the FRS100 and all connected devices. Failure to do so
might cause electric shock.
Do not connect a solenoid valve to the high potential side of the circuit.
If a ground fault occurs, the ground fault current may energize and
open the solenoid valve. This device will not be able to prevent the
valve from opening and fuel from flowing out.
Even after the power to this device is turned off, terminal F continues
to hold an electrical charge. To avoid electrical shock, do not touch ter-
minal F.
Carry out the pilot turndown test carefully. If the flame detector is set
so that it detects a pilot flame that is too small to ignite the main burn-
er, this device will not be able to detect a flame failure in the main burn-
er. In that case, fuel will continue to be supplied, causing a serious
explosion hazard.
Before the pilot turndown test or ignition spark response test, make
sure that all manual fuel valves are closed.

iii
WARNING
If the pilot turndown test must be carried out repeatedly, completely
shut down all equipment each time the test is finished, and completely
discharge unburned gas or fuel that has accumulated in the ducts and
combustion chamber. Failure to discharge unburned gas or fuel may
result in an explosion.
When the pilot turndown test is complete, turn OFF the power switch to
shut down the power. Restore all test jumpers and limit interlock/regu-
lator settings to their previous states. If operation begins without the
above steps, damage to the equipment, gas leak or explosion may
result.
Do not start regular operation of the equipment without first complet-
ing the trial-run adjustments for this device, as well as the tests speci-
fied by the combustion equipment manufacturer.
To prevent electric shock, turn the power off and discharge terminals F
and G before removing this device from the subbase. Use lead wires to
connect terminals F and G of the flame simulator (FSP300C100) to ter-
minals F and G of this device for 10 seconds or more.
CAUTION
Installation, wiring, inspection, adjustment, etc. should be carried out
by a trained and experienced technician who has knowledge and
technical skills related to combustion equipment and flame safeguard
control devices.
Do not install where exposed to any of the following:
• Certain chemicals or corrosive gases (ammonia, sulfur, chlorine,
ethylene compounds, acid, etc.)
• Splashing water or excessive humidity
• High temperatures
• Prolonged vibration
If timers and auxiliary relays are needed for additional functions, select
ones with high reliability, and be sure to design the circuit correctly.
When installing and wiring, be sure to follow the instructions in this
manual and in the user's manual for the combustion equipment.
Make sure the flame detector does not detect ultraviolet rays other
than those of the burner flame. If the flame detector responds to other
ultraviolet rays, it will report that there is a flame even if the burner
flame goes out. As a result, fuel will continue to be discharged,
causing a very serious explosion hazard.

iv
CAUTION
Follow all applicable regulations when doing the wiring work.
Connect the blue signal lead from the AUD100 series Advanced
Ultraviolet Flame Detector to terminal 5 and the white lead to terminal
6. Turning on the power when the flame detector is incorrectly wired
could damage the AUD15C tube unit.
Run the high-voltage ignition transformer cable separately and keep it
at least 10 cm away from this device.
Make sure that ignition transformer high-voltage cables are properly
connected to prevent faulty contact. Faulty contact might generate
high-frequency radio waves which can cause malfunction.
The ignition transformer ground lead should be connected directly to
the burner body or to a metallic part electrically connected to the
burner body.
Keep power lines and ignition transformer high-voltage cables
separate from the flame detector wires.
Always supply electric power at the voltage and frequency stated on
the model label of this device.
Always connect the power supply last. Otherwise, touching a terminal
accidentally could result in electric shock or damage.
In keeping with technical standards for electrical equipment, the burner
body must have an earth ground connection with a resistance of less
than 100 Ω.
After the wiring is complete, be sure to check that it is correct.
Incorrect wiring may cause damage or faulty operation.
Make sure that the flame detector does not detect the ignition spark. If
the flame detector can detect the spark, change the detector's line of
sight or change the ignition electrode's position.
Only an experienced technician who has knowledge and technical
skills related to combustion equipment and combustion safety should
carry out the pilot turndown test.
This product is equipped with functions that are extremely important
for the safe operation of combustion equipment. Carefully follow the
instructions for its use that are given in this user's manual.

v
CAUTION
If the safety shutoff has been activated, check all of the items on the
checklists in Chapter 3, ADJUSTMENTS FOR TRIAL OPERATION
before restarting the equipment.
Check the flame current at least once per month. Doing so can prevent
shutdowns caused by a weak flame current signal.
This device has an operating life. Assuming that the operating life of
the combustion equipment used with this device is longer, be sure to
do periodic maintenance and replacement of this device.
In the event that this device is replaced, do all of the checks listed in
Chapter 3, ADJUSTMENTS FOR TRIAL OPERATION.
When doing a maintenance inspection of the burner, be sure to do the
pilot turndown test. Inspection must be done at least once a year.
Conduct periodic inspections in accordance with the user's manual of
the equipment manufacturer.
When cleaning the burner, clean the flame detector as well.
Do not transport this device while it is mounted on a DIN rail. Remove
it from the subbase and pack it in its original box. If it is transported
while on a DIN rail, it might fall off and be damaged.

Conventions Used in This Manual
vi
The following conventions are used in this manual:
Handling Precautions:
Handling Precautions indicate items that the user should pay attention to
when handling the FRS100.
Note: Notes indicate information that might benefit the user.
(1), (2), (3): Numbers within parentheses indicate steps in a sequence or parts of an
explanation.

Contents
vii
SAFETY PRECAUTIONS
Conventions Used in This Manual
Chapter 1. OVERVIEW AND PRODUCT CONFIGURATION
■Overview •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
■Features •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
■System configuration ••••••••••••••••••••••••••••••••••••••••••••••••••••1
■Security function•••••••••••••••••••••••••••••••••••••••••••••••••••••••••2
■Precautions for facility instrumentation••••••••••••••••••••••••••••••••••2
■Model selection guide••••••••••••••••••••••••••••••••••••••••••••••••••••3
■Names of parts•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••4
■Configuration ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••4
Chapter 2. MOUNTING AND WIRING
2-1 Mounting and Wiring the Subbase•••••••••••••••••••••••••••••••••••••••••••5
2-2 Wiring••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••8
■Manual ignition (intermittent pilot) •••••••••••••••••••••••••••••••••••••••9
■Burner flame monitoring only ••••••••••••••••••••••••••••••••••••••••••14
■Wiring the flame detector •••••••••••••••••••••••••••••••••••••••••••••••19
■Wiring the solenoid valve •••••••••••••••••••••••••••••••••••••••••••••••20
■Wiring the surge absorber ••••••••••••••••••••••••••••••••••••••••••••••21
Chapter 3. ADJUSTMENTS FOR TRIAL OPERATION
■Outline ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••22
■How to measure the flame signal •••••••••••••••••••••••••••••••••••••••23
■Pilot turndown test •••••••••••••••••••••••••••••••••••••••••••••••••••••24
■Ignition spark response test ••••••••••••••••••••••••••••••••••••••••••••26
■Safety shutoff test ••••••••••••••••••••••••••••••••••••••••••••••••••••••27
Chapter 4. MAINTENANCE AND INSPECTION
■Frequency of maintenance and inspection •••••••••••••••••••••••••••••28
■Troubleshooting ••••••••••••••••••••••••••••••••••••••••••••••••••••••••29
Chapter 5. SPECIFICATIONS
■Specifications ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••32
■External dimensions ••••••••••••••••••••••••••••••••••••••••••••••••••••33

Chapter 1. OVERVIEW AND PRODUCT
CONFIGURATION
1
■Overview
The FRS100 Multiburner Controller is a combustion safety control with a safe-
start circuit, for use with manually ignited combustion equipment. To ensure safe-
ty, the FRS100 prevents ignition if anything abnormal is detected at start up, and
shuts off the fuel valve if a flame failure occurs during operation. It is used in con-
junction with the AUD100 series advanced ultraviolet flame detector or flame rod
for batch operation of a burner. For continuous burner operation (nonstop combus-
tion for 24 h or longer), instead of the FRS100, use the AUR350C, which has a
continuous self-checking function.
Because the FRS100 does not have an ignition function, it is used for systems in
which an operator ignites the burner manually. This device should be used in com-
bination with external instrumentation that supplies a purge function.
Key Characteristics of the FRS100
■Features
• Upon equipment startup, the FRS100 checks both itself and the flame detector.
If anything abnormal is detected, the FRS100 prevents ignition to ensure safety.
• The FRS100 is designed to be compact, and can be plugged into the wiring
sub-base. The sub-base can be mounted by screws or onto a DIN rail.
• The power supply state and ignition detection can be verified easily from the
LEDs on the front display. Completion of the start check is indicated by the
LED on the center of the body behind the front cover.
• Flame voltage output (0 to 5 Vdc) can be checked by the FSP136A100, or
continuously monitored by a panel meter or recorder.
■System configuration
In terms of the overall system, the FRS100 serves as the flame monitoring device.
It is used as shown in the diagram below.
Compatible Purge Ignition Flame Behavior if Compatible
burner function function monitoring flame failure flame
operation type occurs detectors
Batch No No Yes Does not
AUD100C + AUD15C
recycle AUD110C + AUD15C
Flame rod
Air pressure
lower interlock
Gas pressure
lower interlock
Gas pressure
upper interlock
Ignition
transformer
Air
Fuel
MV MV
PV PV
T/C T/C
Temperature
controller
L
LH
High limit controller
Combustion
chamber
Combustion equipment
FRS100
PS
PS
IG
PS
Flame
detector
Exhaust

2
Chapter 1. OVERVIEW AND PRODUCT CONFIGURATION
■Security function
The FRS100 is designed to ensure safety, and plays an important safety role by
monitoring the burner operation and the flame.
1. Combustion monitoring and safety shutoff
• Detects flame failure in the burner and quickly shuts off the fuel and shuts
down the burner.
• When an ignition failure, flame failure or flame-out occurs, the FRS100 fol-
lows a fixed sequence in shutting down each piece of equipment.
2. Startup, operation, and shutoff of combustion equipment
• The FRS100 operates each device according to a predetermined sequence
and timing.
3. Safe startup
• At every startup signal, the FRS100 checks for false flame in the flame detec-
tor and flame detection circuit.
• If a problem is detected, the FRS100 does not start the burner.
4. Redundant design
• Maintains safety even if its own self-check circuit fails.
• Will not deviate from the proper ignition sequence.
■Precautions for facility instrumentation
In designing facilities that use combustion safety devices, be sure to give careful
consideration to the safety guidelines listed below.
• For safety standards for industrial facilities using combustion equipment, see the
technical guidelines published by the Ministry of Health, Labour and Welfare
• For general safety rules for industrial combustion furnaces, see JIS B 8415.
• For technical safety guidelines for gas combustion furnaces in industrial use, see
publications by the Japan Gas Association.
• For technical safety guidelines for gas boiler combustion equipment, see publica-
tions by the Japan Gas Association.
●Important points for ensuring safety
1. Connect the load directly to the FRS100.
2. Design the interlock so that it can directly cut off power to the load.
3. Be sure to use a safe startup circuit upon startup.
4. Do not set up a bypass, such as manual operation, for any load.
5. Have a redundant main valve and pilot valve.
●Precautions for system design
Since the FRS100 does not have purge or ignition functions, they must be provid-
ed externally.

■Model selection guide
*1. Discontinuation date: Dec. 2011.
*2. Discontinuation date: March 2012.
*3. Please put "D" in if inspection report is attached. Skip if there is no inspec-
tion report.
3
Chapter 1. OVERVIEW AND PRODUCT CONFIGURATION
Model No. Rated power supply
FRS100B100 -2 100 Vac 50/60Hz
FRS100B200 -2 200 Vac 50/60Hz
FRS100B104 -2 100 Vac 50/60Hz
FRS100B204 -2 200 Vac 50/60Hz
FRS100C100 -2 100 Vac 50/60Hz
FRS100C200 -2 200 Vac 50/60Hz
FRS100C300 -2 220 Vac 50/60Hz
FRS100C104 -2 100 Vac 50/60Hz
FRS100C204 -2 200 Vac 50/60Hz
FRS100C304 -2 220 Vac 50/60Hz
FRS100C150 -2 100 Vac 50/60Hz
FRS100C250 -2 200 Vac 50/60Hz
FRS100C350 -2 220 Vac 50/60Hz
FRS100C154 -2 100 Vac 50/60Hz
FRS100C254 -2 200 Vac 50/60Hz
FRS100C354 -2 220 Vac 50/60Hz
Power
consumption
3W max.
7W max.
7W max.
Flame failure
response
3 ±1 s
(when flame voltage is 2 V)
2 s max.
(when flame voltage is 2 V)
3 ±1 s
(when flame voltage is 4.2 V)
2 s max.
(when flame voltage is 4.2 V)
3 ±1 s
(when flame voltage is 3.5 V)
2 s max.
(when flame voltage is 3.5 V)
Flame detector
C7007A, C7008A
Flame Rod
C7012A*2, C7012C*2
Ultraviolet Flame
Detector
AUD100C + AUD15C
AUD110C + AUD15C
Advanced Ultraviolet
Flame Detector
C7035A*1, C7027A*1
Minipeeper Ultraviolet
Flame Detector
Model
Standard
model
High-sensitivity
model

■Names of parts
●FRS100 body
●FRS50A100 subbase (sold separately)
■Configuration
●Flame Detector
FRS100B FRS100C
*2. Discontinuation date: March 2012.
*1. Discontinuation date: Dec. 2011.
●Optional Parts (sold separately)
*1. Discontinuation date: Dec. 2011.
Chapter 1. OVERVIEW AND PRODUCT CONFIGURATION
Cover
POWER
FLAME
START
LEVEL
LEVEL
:Voltagedisplayed
 54.5Vorhigher
 43.5to4.5V
 32.5to3.5V
 21.5to2.5V
DINrail
mountingplate
Name Model No.
Advanced Ultraviolet Flame
AUD100C + AUD15C
Detector AUD110C + AUD15C
Minipeeper Ultraviolet Flame C7035A*1, C7027A*1
Detector
Name Model No.
Ultraviolet Flame Detector C7012A/C*2
Flame Rod C7007A, C7008A
Name Model No. Name Model No.
Subbase FRS50A100 Flame Simulator for 123514A
Flame simulator for FSP300C100 Flame Rod
AUD100C/110C + AUD15C, Lightning surge absorber 83968019-001
C7035A*1, C7027A*1
4

Chapter 2. MOUNTING AND WIRING
2 - 1 Mounting and Wiring the Subbase
●Mounting location
Maintain space around the control as shown below for heat radiation, and to facili-
tate mounting, removal, wiring and maintenance.
Handling Precautions
• If there is room, leave as much space as possible between the FRS and
other FRS units to allow for heat radiation.
• If ambient temperature is close to the allowable upper limit, reduce the
internal temperature of the control panel by mounting a panel cooler or a
cooling fan.
Allowable ambient temperature upper limits
• Gang-mounting: 45 °C
• Stand-alone mounting: 60 °C
5
CAUTION
Do not install where exposed to any of the following:
• Certain chemicals or corrosive gases (ammonia, sulfur, chlorine, ethylene
compounds, acid, etc.)
• Splashing water or excessive humidity
• High temperatures
• Prolonged vibration
Do not transport this device while it is mounted on a DIN rail. Remove it from
the subbase and pack it in its original box. If it is transported while on a DIN
rail, it might fall off and be damaged.
When installing and wiring, be sure to follow the instructions in this manual
and in the user's manual for the combustion equipment.
POWER
FLAME
START
LEVEL
POWER
FLAME
START
LEVEL POWER
FLAME
START
LEVEL
Above: 50 mm min.
20 mm min.
Below: 20 mm min.
20 mm min.
Gang-mounting
(Allowable ambient temperature upper limits: 45 °C)
Below: 20 mm min.
Stand-alone mounting
(Allowable ambient temperature upper limits: 60 °C)
Above: 50 mm min.
20 mm min.
20 mm min.

6
●Mounting direction
• Mount in a vertical plane so that the arrow on the subbase is facing upwards.
• Mount so that the indicators are at the top of the front panel.
• Do not mount as shown below.
●DIN rail mounting
(1) Pull the DIN rail mounting plate downwards.
(2) Place the subbase on the DIN rail so that the arrow on the subbase is facing
upwards.
(3) Lock the subbase to the DIN rail by pushing the mounting plate upward.
Chapter 2. MOUNTING AND WIRING
POWER
FLAME
START
LEVEL
Indicator

UP UP
UP UP UP
Pull down Mount the subbase Push the DIN rail
mounting plate
upward
UP

7
(4) Wire the subbase terminals as instructed in 2-2 Wiring.
(5) Pull the bottom of the controller cover downwards to remove.
(6) Press the controller into the subbase with the display facing upwards.
(7) Tighten the mounting screw on the center of the body to fix onto the subbase
with a maximum torque of 0.3 N•m.
(8) If necessary, wire the flame voltage meter terminals.
(9) Mount the cover on the control body.
●Direct panel mounting
(1) Drill two M4 mounting holes in the panel so that the arrow on the subbase will
be facing upward.
(2) Attach the subbase to the panel using two M4 screws at a maximum torque of
0.7 N•m.
Handling Precautions
• Do not tighten the subbase mounting screws using a torque exceeding
the maximum torque. Doing so might damage the subbase.
(3) Wire the subbase terminals as instructed in 2-2 Wiring.
(4) Pull the bottom of the controller cover downwards to remove.
(5) Press the controller into the subbase with the display facing upwards.
(6) Tighten the mounting screw on the center of the body to fix onto the subbase
with a maximum torque of 0.3 N•m.
(7) If necessary, wire the flame voltage meter terminals.
(8) Mount the cover on the control body.
F
L
A
M
E
R
ELA
Y
SN
POWER
FLAME
START
LEVEL
POWER
FLAME
START
LEVEL
Tighten the screw
and fix
Subbase
FRS100
Cover
Push the FRS100
into the subbase
Flame voltage
meter terminals
Chapter 2. MOUNTING AND WIRING
32
UP M4 (2 locations)

2 - 2 Wiring
8
Chapter 2. MOUNTING AND WIRING
WARNING
Wire terminals 1 and 2 so that they receive power continuously whenever the
power switch is turned on. This is absolutely necessary to ensure operation
of the self-check circuits at startup.
Therefore, do not wire a thermostat between the power switch and terminal 1
or 2. Doing so might cause a serious combustion equipment accident.
Connect loads (ignition transformer, solenoid valve, etc.) directly to the output
terminals of this device. If they are not directly connected, combustion safety
cannot be ensured.
CAUTION
If timers and auxiliary relays are needed for additional functions, select ones
with high reliability, and be sure to design the circuit correctly
Make sure the load connected to each terminal does not exceed the rating
indicated in the specifications.
When installing and wiring, be sure to follow the instructions in this manual
and in the user's manual for the combustion equipment.
Follow all applicable regulations when doing the wiring work.
Run the high-voltage ignition transformer cable separately and keep it at
least 10 cm away from this device.
Make sure that ignition transformer high-voltage cables are properly
connected to prevent faulty contact. Faulty contact might generate high-
frequency radio waves which can cause malfunction.
The ignition transformer ground lead should be connected directly to the
burner body or to a metallic part electrically connected to the burner body.
Keep power lines and ignition transformer high-voltage cables separate from
the flame detector wires.
Always supply electric power at the voltage and frequency stated on the
model label of this device.
Always connect the power supply last. Otherwise, touching a terminal
accidentally could result in electric shock or damage.
In keeping with technical standards for electrical equipment, the burner body
must have an earth ground connection with a resistance of less than 100 Ω.
After the wiring is complete, be sure to check that it is correct. Incorrect
wiring may cause damage or faulty operation.

9
■Manual ignition (intermittent pilot)
Handling Precautions
•If the power supply high potential (H) and low potential (G) are differenti-
ated, connect the high potential to terminal 1 and the low potential to ter-
minal 2.
Chapter 2. MOUNTING AND WIRING
High potential
(H)
Low potential
(G)
Main valve 1
Main valve 2
Ignition
transformer
Pilot valve 1
Flame detector
Start check circuit
8
31K
1K
2K 4
Combustion
lamp
Power
Ignition switch
Flame voltage
0-5 Vdc
Internal circuit
B
A
7
Subbase
Burner start
contacts
(F)
(G) 6
5
Flame
amplifier circuit
2K
Power circuit
21
−
＋
Pilot valve 2
Prepurge
completion
signal
Blower on-off circuit /
Prepurge circuit
Limit/Interlock circuit
(limit switch, interlock switch)
Operation
input circuit
* The combustion lamp lights up
when the ignition switch is turned on.
*

10
●Explanation of operation
• Normal operation and shutdown
Chapter 2. MOUNTING AND WIRING
No Input status FRS100 activity Output activity
1 Power ON Receives power across terminals 1 and 2. (POWER LED lights up)
2 Blower operation If the limit switch and interlock status is normal,
the blower starts. After completion of the prepurge,
the prepurge completion signal is transmitted to
allow execution of the next operation.
3 Burner start If the limit switch and interlock status is normal (Start check operation LED
contacts ON (limit switch contacts closed), when the burner lights up)
start contacts are closed, power is applied across
terminals 7 and 2. Relay 1K turns on after
completion of the start check.
4 Ignition switch ON When the ignition switch is pushed (contacts closed), •Ignition transformer ON
power is applied from terminal 8 to the pilot valve •Pilot valve opens
and ignition transformer. The ignition transformer •Combustion lamp lights
turns on, the pilot valve opens, and the combustion up
lamp lights up.
The flame detector detects the pilot burner flame, •(FLAME LED lights up)
and relay 2K turns on, allowing power to be
supplied through terminal 4.
5 Ignition switch OFF Since the ignition switch contacts are open, power •Ignition transformer OFF
to the ignition transformer is cut, and ignition •Pilot valve continues
transformer operation stops. open
Because power is supplied through relays 1K and •Main valve opens
2K, power through terminal 4 continues to maintain
the operation of the pilot valve. When the ignition
switch is turned off, its N.C. contacts close, supply-
ing power to the main valve, which opens.
6 Blower stop Since the prepurge completion signal has been •Pilot valve closes
discontinued, the power across terminals 7 and 2 •Main valve closes
is cut, relay 1K turns off, and the power to terminal (FLAME LED turns off)
4 is also cut. The pilot and main valves close, and •Combustion lamp turns
the combustion lamp turns off. off
All loads are de-energized, and when the flame •(Start check operation
detector detects the flame failure, relay 2K turns off. LED turns off)
The FRS100 returns to standby status and waits
for the next start signal.
Limit/Interlock contacts
(1)Power ON
(3)Burner start contacts ON
(4)Ignition switch ON
Flame detection
Start check (2s)
Blower operation
Prepurge
Prepurge completion signal
(5)Ignition switch
OFF (5-10s)
(6)Blower stop
(2)Blower operation
Elapsed time
Ignition transformer
Pilot valve
Combustion lamp
POWER LED
FLAME LED
Start check LED
Main valve
Burner start contacts (term.7-2)
Note: It is possible that relay 2K may turn ON when the power is turned on.