Merrychef eikon
®
e2s service and repair manual
62
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5 Service information
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•
208 – 240V Transformer
High voltage diode test
Ensure the following requirements have been met before starting the test:
§
The appliance has been disconnected from the power supply and protective measures have been taken to ensure
the power cannot be switched on again.
§
The appliance is cool.
§
The high voltage capacitors are discharged before commencing work.
See section 2.15 ‘How to discharge the e2s HV’
§
The casing of the appliance has been removed.
DANGER
High voltages and significant currents are present at the high voltage capacitor and HV Circuit.
It is very dangerous to work near this part when the oven is on.
NEVER make any electrical measurements on the high voltage circuits, including the magnetron filament, whilst the oven is
connected to the mains power supply.
High voltage capacitor test
Ensure the following requirements have been met before starting the test:
§
The appliance has been disconnected from the power supply and protective measures have been taken to ensure
the power cannot be switched on again.
§
The appliance is cool.
§
The high voltage capacitors are discharged before commencing work.
See section 2.15 ‘How to discharge the e2s HV’
§
The casing of the appliance has been removed.
6.
Using a megger/insulation tester, test the insulation resistance between:
Primary winding and chassis. Pass if reading is over 10 M
Ω
Filament winding and chassis. Pass if reading is over 10 M
Ω
NOTE: One end of the high voltage (secondary) winding is connected to the chassis, so this is not
tested.
1.
Remove both connections from the high voltage diode.
2.
Using a megger/insulation tester, test for continuity in both
directions.
Results should be as follows:
Open circuit both ways - FAIL
Conducts one-way only - PASS
Short circuit both ways - FAIL
Conducts one way, leaks the other – FAIL
Note: The diode flows to chassis ground
3.
Mains winding between tags,
approx.;
0 to 200/208; 0.5
Ω
0 to 220; 0.6
Ω
0 to 240; 0.6
Ω
208/208 to 220; 0.1
Ω
208/208 to 240; 0.1
Ω
220 to 240; 0.1
Ω
4.
High Voltage winding, approx.
47
Ω
.
5.
Filament winding between
terminals, less than 1
Ω
.