5.5.Inverter power supply (U)
DO NOT try to REPAIR H.V. Inverter power supply (U). Replace complete H.V. Inverter(U) Unit.
WARNING: HIGH VOLTAGE
Test if failure codes H95, H97 or H98 appear when performing the following procedure. It is recommended to use an AC line input current ammeter for testing.
Test 1
1.With the oven unit’s AC power supply cord is unplugged from the wall outlet, unplug the 2 pin H.V. connector CN703 from the magnetron tube.
2.Place 1 liter of water load into oven cavity.
3.Plug in the oven’s AC power supply cord into outlet.
4.Program DPC.
a.Press Timer/Clock pad twice.
b.Press Start pad once.
c.Press Power Level pad once.
5.Program oven at High power for 1 minute and press [Start] pad.
a.After approximately 37 seconds, oven stops operating.
b.During oven operation, the input current is approximately 0.5 to 1A. If both a and b are OK, proceed to test 2.
| INPUT CURRENT | FAILURE CODE |
Unplug CN703 | 0.5 to 1A | Oven stops in 37 |
|
| seconds after started. |
Test 2
Continued from Test 1
1.Unplug the oven’s AC power supply cord from outlet.
2.Unplug 3 pin connector CN701. CN703 remains unplugged.
3.Plug in the oven’s AC power supply cord into outlet.
4.Program DPC.
a.Press Timer/Clock pad twice.
b.Press Start pad once.
c.Press Power Level pad once.
5.Program oven at High power for 1 minute and press [Start] pad.
a.After approximately 3 seconds, oven stops operating.
b.During oven operation, the input current is approximately 0.4A.
| INPUT CURRENT | FAILURE CODE |
Unplug CN701 | 0.4A | Oven stops in 3 |
seconds after started.
If both a and b check OK, the Inverter Power Supply (U) can be determined to be OK.
5.6.Temperature thermistor
These sensor monitors the heat produced by the heater circuit and maintains the magnetron temperature which user had selected. Normal room temperature 10°C to 30°C, the reading across the temperature thermistor should be as follows.
TEMP | MAGNETRON THERMISTOR |
100°C | |
25°C |
If the resistance reading is out of the range stated here, the thermistor is detective and must be replaced.
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