
13
RE220002 Rev. 6
High voltages are present during the cook cycle.
Extreme caution should be observed at all times.
Before touching any oven components or wiring,
always unplug the oven from its power source and discharge the
capacitor by shorting across the capacitor terminals with an insulated handle screwdriver.
DANGER
!
Test Procedures
High Voltage Component Test Chart
COMPONENT
TEST SET-UP
NORMAL READING (Approximate)
CAPACITOR
DISCHARGE THE CAPACITOR
BETWEEN TERMINALS: Analog meter
Remove wires from capacitor terminals
and connect ohmmeter, set on highest
resistance scale to terminals.
should momentarily deflect toward zero
then return a resistance greater than 5 meg
ohms. If no deflection occurs, or if
continuous deflection occurs, replace
capacitor.
Also check between each terminal and
the capacitor case.
TERMINAL TO CASE: Infinite resistance.
DIODE
DISCHARGE THE CAPACITOR Isolate the
diode by disconnecting the wiring. On
type I diodes remove both wires. On type II
diodes disconnect one wire to diode.
Infinite resistance should be measured in
one direction and 50,000 to 200,000 ohms
in the opposite direction:
TYPE I
It is not necessary to remove the mounting
screw.
Connect ohmmeter, set on highest
resistance scale, to diode terminals.
NOTE: Ohmmeter must be an analog meter
and contain a battery of 6 volts minimum.
TYPE II
Reverse meter leads for second testing.
On type I diodes, test from each terminal
to ground.
EACH TERMINAL TO GROUND:
(Type I only) Infinite resistance.
MAGNETRON
DISCHARGE THE CAPACITOR
BETWEEN TERMINALS :
Less than 1 ohm.
Remove wires from magnetron and
connect ohmmeter to its terminals.
EACH TERMINAL TO GROUND:
Infinite resistance.
Also check between each terminal
and ground.
NOTE: This test is not conclusive. If the
oven does not heat and all other
components test good replace the
magnetron and retest.
POWER TRANSFORMER
DISCHARGE THE CAPACITOR
To check primary winding, remove wires
from terminals (marked 1 & 2 FS-10 EVP,
VEND-10, or COM & 208 OR 240
FS-14 EVP). Connect ohmmeter between
primary terminals.
PRIMARY: Less than 1 ohm
Check from each primary terminal to ground.
EACH TERMINAL TO GROUND:
Infinite resistance
Also check high voltage winding, remove
wire from either secondary terminal marked
HI or LO terminal and oven chassis ground.
HI TO GROUND:
40 to 80 ohms DEPENDING ON
LO TO GROUND: TRANSFORMER
40 to 80 ohms MANUFACTOR
To check filament windings, remove
filament leads 3 & 4 and measure
resistance across leads.
Also check between each terminal
and ground.
FILAMENT:
Less than 1 ohm
FILAMENT TO GROUND:
Infinite resistance.