Electrolux E30SO75ESS - 30" Wall Oven, Service Manual

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8
E30SO75ESS
Figure O-1. Oven Schematic-OFF Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1.
DOOR CLOSED.
2. CLOCK APPEARS ON DISPLAY.
SCHEMATIC DIAGRAM
time. And the oven will cook according to the special cooking
sequence.
FIRE SENSING FEATURE (MICROWAVE MODE)
This model incorporates a sensing feature which will stop
the oven's operation if there is a fire in the oven cavity during
microwave cooking. This fire sensing feature will operate
when the microwave power level is set to 80% or more. This
is accomplished by the LSI repeatedly measuring the volt-
age across the temperature measurement circuit (thermis-
tor) during it's 32-seconds time base comparing the ob-
tained voltage measurements. If the most recent voltage
measured is 300 mV greater than the previous voltage
measured, the LSI judges it as a fire in the oven cavity and
switches off the relays to the power transformer, fan motor
and convection motor. The LSI also stops counting down
and closes the damper door so that no fresh air will enter the
oven cavity. Please refer to the following section for a more
detailed description.
Operation
Please refer to the timing diagrams below.
1. The fire sensing will start after 30 minutes when the oven
is started.
2. The thermistor operates within a 32-seconds time base
and it is energized for three (3) seconds and off for 29
seconds. Two (2) seconds after the thermistor is
energized, the voltage across the temperature
NOTES:
1. Circuits / Wire Colors subject to change without notice.
LV TRANSFORMER
C
2
C
1
C
4
C
3
T6
T7
T4 A3
T2 A1
D9
R
Y
2
R
Y
1
R
Y
5
R
Y
4
R
Y
3
RY6
R
EC
TI
FI
ER
SOLID-STATE RELAY
IN
TE
R
LO
C
K
R
EL
A
Y
P
R
IM
A
R
Y
SECONDARY
INTERLOCK
SWITCH
FA
N
M
O
TO
R
UNIT
CONTROL
M
O
N
IT
O
R
S
W
IT
C
H
1
.0
μ
F
C
A
P
A
C
IT
O
R
A
C
2
3
0
0
V
M
A
G
N
ET
R
O
N
RED
BLK
D
A
M
P
ER
SW
IT
C
H
SW
IT
C
H
D
O
O
R
SE
N
SI
N
G
JE
T
M
O
TO
R
TU
R
N
TA
B
LE
M
O
TO
R
N
.O
.
N
.O
.
JM
D
M
FM
FM
O
L
TT
M
TH
ER
M
IS
TO
R
SOLID-STATE RELAY
SI
D
E
H
EA
TE
R
TO
P
H
EA
TE
R
C
O
M
.
C
O
M
.
D
A
M
P
ER
M
O
TO
R
B
3
B
4
B
1
B
2
B5
B
6
D
7
D
5
D
3
E3 E5
E1
SIDE HEATER
CUT-OUT
THERMAL
CUT-OUT
TOP HEATER
THERMAL
MG.
FUSE
TEMP.
O
V
EN
L
A
M
P
F10A
FUSE
D
1
W
IT
H
1
5
0
°C
T
H
ER
M
O
ST
A
T
TR
A
N
SF
O
R
M
ER
P
O
W
ER
IN
P
R
IM
A
R
Y
W
IN
D
IN
G
GND
2
4
0
V
6
0
H
z
R
ED
GRY
RED
BLK
BLK
RED
BRN
B
LK
RED BRN
BLK
R
ED
R
ED
B
LK
O
R
G
BRN
ORG
BRN
RED
BLK
O
R
G
B
LK
O
R
G
B
LK
O
R
G
R
ED
R
ED
R
ED
O
R
G
O
R
G
O
R
G BLK
R
ED
G
R
Y
W
H
T
G
R
Y
B
LK
G
R
Y
G
R
Y
G
R
Y W
H
T
G
R
Y
W
H
T
G
R
Y
G
R
Y
W
H
T
G
R
Y
W
H
T
G
R
Y
W
H
T
W
H
T
R
ED
B
LU
GRY WHT
WHT GRY
N.O. COM.
G
R
Y B
LK
WHT
GRN
B
LK
O
R
G
B
LU
B
LK
R
ED
B
LK
B
LU
B
LU
R
ED
G
R
N
BLK
BRN
GRN
WHT
GRN
GRN
W
H
T
O
R
G
R
ED
T1
T3
FUSE12.5A
NOTE: " " indicates components with potential above 250V.
measurement circuit is sampled by the LSI and twenty
five (25) seconds after the thermistor is cut off the LSI
turns on the convection fan for three (3) seconds.
3. The above procedure is repeated. If the difference between
the first voltage measured (in step 1) and the voltage
measured when the procedure is repeated (step 2) is
greater than 300 mV the LSI makes the judgment that
there is a fire in the oven cavity and will switch off the relays
to the power transformer, fan motor and convection motor.
The LSI also stops counting down and closes the damper
door so that no fresh air will enter the oven cavity.
4. Once the fire sensor feature has shut the unit down, the
programmed cooking cycle may be resumed by pressing
the "START" pad or the unit may be reset by pressing the
"CLEAR" pad.
CONVECTION
MOTOR
THERMISTOR
Sensing
Voltage
ON
OFF
ON
OFF
ON
OFF
0 2 3 28 31 32 (sec.) 64 (sec.)
3 sec.
Sensing the voltage across temperature measurement circuit.
3 sec.