Smart Interface Board (Sib) - Frymaster FilterQuick easyTouch FQG60T Service Manual

1.10

Smart Interface Board (SIB)

All fryers in this series have a smart interface board (SIB)
located in the component box behind the controller panel.
The SIB board provides a link between the controller and
the fryer's individual components without requiring
excessive wiring and executes commands from one
central point.
K2 is a single-pole-double throw (SPDT) relay that supplies
24VAC to the ignition and gas valve circuits. The relays on
this board are soldered to the board. If a relay fails, the board must be replaced. K1 is a single-pole-double throw
(SPDT) relay that supplies voltage through the high limit and the optional air pressure switch.
The SIB LEDs (labeled LED1 through LED7) are arrayed around the board to assist in troubleshooting.
12VDC should be lit and bright at all times.
If LED is dim then something is pulling
voltage down. Short to ground on 12VDC
circuit will cause dim LED.
When UI is soft
powered on this
Latch Relay LED
will come on first
confirming high
limit is closed.
The blower will
then come on
and prove the air
switch. The relay
is a true latch
circuit and when
broken or turned
off the heat relay
will also turn off.
When UI calls for HEAT this LED will
come on with the heat relay only after
latch relay has been latched in and
AIR switch has been proven. This LED
will cycle with the call for heat.
NOTE: Refer to Section 1.17.1 for troubleshooting flowchart.
The chart on pages 1-9 illustrates current flow through the board, and the table at the top of page 1-10 identifies
frequently used test points.
12VDC
Green
LED
LED 2
Latch Relay
Blue
LED
2 1
LED 3
1
Latch Relay
Control
K1
Heat Relay
Blue
1
LED
20
Heat Relay LED 1
J1
K2
1
1
Ignition
P-Bus
J2
Module
2
24
Blinking red LED, (Heartbeat). This
LED should be blinking and bright
at
powered. The other green LED's
being dim or off will cause this
LED to be off.
SMART INTERFACE BOARD LED
LED 1 24VAC Heat Relay
LED 2 12VDC to Controller
LED 3 24VAC Latch Relay
LED 4 5VDC to probes and switches
LED 6 3.3VDC to Micro Processor
LED 7 Communication to/from Micro Processor
5VDC should be lit and bright at all
times. If LED is dim then something is
pulling voltage down. Short to ground
on 5VDC circuit will cause dim LED.
5VDC
Green
LED
LED 4
12VDC
Test
Point
Smart Interface (SIB)
Board
6
1 6 1
P-Bus UI Interface
J10 J9 J6
all times when board
1-8
DIAGNOSTIC LIGHTS
5VDC
Test
Point
Cook
1
Probe
2
Red 1
ATO
2
Comm.
Probe
3
LED
LED 7
3.3VDC
Green
Ground
LED
Test
LED 6
Point
3.3VDC
Test
8 1 4 1 4
Point
C-Bus C-Bus
J8 J7
8075729
3.3VDC LED should be lit and
bright at all times. If dim, then
is something is pulling voltage
down. Short to ground on
3.3VDC circuit will cause dim
LED.
J11
J3