1-2

The normally-closed (N.C.) contacts of relay 4 provide a potential circuit for the Base Thermal

Fuse. If the base of the oven exceeds 133˚F, the thermal fuse contacts close, and a circuit for

the low-speed side of the blower motor is completed, which turns the motor on. The low-speed

blower will operate until the base temperature drops below 104˚F and opens the thermal fuse

contacts, and turns off.

NL1
20A LINE
FUSE
CAVITY
THERMAL
FUSE
MAGNETRON
THERMAL
FUSE
BK
BK
BK
RELAY 4
BASE
THERMAL
FUSE
W
BL
YL
LOW-VOLTAGE
TRANSFORMER
W
BLOWER
MOTOR
RD
MICROCOMPUTER
BOARD
3 1
11
CAPACITOR
RD RD
(C)(HIGH)

When the low-speed fan is selected by the user at the control panel, relay 3 and the normally-

closed (N.C.) contacts of relay 4, complete the circuit to the low-speed windings of the blower

motor and turn it on.

NL1
20A LINE
FUSE
CAVITY
THERMAL
USE
MAGNETRON
THERMAL
FUSE
BK
RDBK
RELAY 4
W
BL
PK/W
LOW-VOLTAGE
TRANSFORMER
BLOWER MOTOR
RD
RELAY 3
MICROCOMPUTER
BOARD

3 1

9

CAPACITOR
RDRD
(LOW) (C)

When the high-speed fan is selected by the user at the control panel, the normally-open (N.O.)

contacts of relay 4 complete the circuit to the high-speed windings of the blower motor and turn

it on.

N
L1
20A LINE
FUSE
CAVITY
THERMAL
FUSE
MAGNETRON
THERMAL
FUSE
BK
RD
BK
RELAY 4
W
BL
BK
LOW-VOLTAGE
TRANSFORMER
BLOWER MOTOR
RD
MICROCOMPUTER
BOARD
3 113
CAPACITOR
RDRD
(HI) (C)