19
R-22GV
R-22GT
R-23GT
R-24GT
TEST PROCEDURES (CONT'D)
PROCEDURE
LETTER
COMPONENT TEST
damage and examine the transformer with
a tester for the presence of layer short-
circuit (check primary coil resistance which
is approximately 270
Ω
±
10% for R-22GV/
R-22GT, and approximately 865
Ω
±
10%
between 208V terminals and 970
Ω
±
10%
between 230V terminals for R-23GT/R-
24GT). If any abnormal condition is de-
tected, replace the defective parts.
7
POWER
POWER
(VRS2)
VRS1
(J1)
12
P
CT1
17
TB1
T1
a
b
c
d
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following units as
shown in the touch control panel circuit.
(1) Control Unit
(2) Key Unit
The principal functions of these units and the signals commu-
nicated among them are explained below.
1. Control Unit
Signal of key touch and oven function control are all
processed by one microcomputer.
1) Power Supply Circuit
This circuit changes output voltage at the secondary side
of the low voltage (T1) transformer to voltages required at
each part by full wave rectifying circuit, constant voltage
circuit, etc..
2) ACL Circuit
This is an Auto-clear Circuit, i.e., a reset circuit, which
enables IC1 to be activated from initial state.
3) Power SYNC Signal Generating Circuit
This is a circuit for generating power SYNC signal by virtue
of the secondary side output of transformer T1.
This signal is used as a basic frequency for time process-
ing.
4) Clock Circuit
This is a circuit for controlling clock frequency required for
operating IC1.
5) IC1 (Main Processor)
This is a one-chip microcomputer, responsible for control-
ling the entire control unit.
6) IC2 (Memory Processor)
This is a memory IC, responsible for memory function.
7) IC3
This is a IC for driving light emitting diode.
8) Display Circuit
This is a circuit for driving light emitting diode by IC1 output.
9) Key Input Circuit
This is a circuit for transmitting key input information to IC1.
10) Sound-body Driving Circuit
This is a circuit for driving sound body by IC1 output.
11) Relay Driving Circuit
This is a circuit for driving output relay by IC1 output.
12) Door Sensing Switch Circuit
This is a circuit for driving IC1 to detect door opening/
closing.
13) Exhaust Air Temperature Detecting Circuit
This is a circuit for transmitting output change of thermistor
(Oven thermistor) to IC1.
14) Magnetron Temperature Circuit
(Detect no load or fan lock)
This is a circuit for transmitting output change of thermistor
(Magnetron Temperature Sensor) to IC1.
15) Intake Air Temperature Detecting Circuit
This is a circuit for transmitting output change of thermistor
(Intake Air Sensor) to IC1.
16) High Voltage Monitoring Circuit.
This circuit detects problems in the magnetron / high
voltage circuit by sensing a variation in the current flowing
through the primary winding of the high voltage trans-
