National NN-V680W, Руководство по обслуживанию

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7.5. Inverter Power Supply (U)
(NEW H.V.)
7.6. Inverter Power Supply (U)
(NEW H,V,)
DANGER HIGH VOLTAGE
Test 1
1. Place 1 liter of water load into oven cavity.
2. Unplug 2 pin H. V. lead wire connector CN703 from
magnetron tube.
3. Program oven at High power for 1 minute and press start.
a. After approx. 23 seconds, oven stops.
b. During oven operation, input current is approx. at 0.5 to
1.0A . If input current is OK, please proceed to test 2.
Test 2
Continued from Test 1
1. Unplug 3 pin connector, CN701 CN703 remaisn unplug.
2. Set oven at High power for 1 minute and start.
a. After approx. 3 seconds, oven.
b. During oven operation, input current should be less than
0.4A.
If both 1 and 2 are OK, the Inverter Power Supply (U) can be
determined OK.
7.7. Steam Sensor and Digital
Programmer Circuit
In order to determine if the steam sensor function of the digital
programmer circuit is in working order or not, do the following
test.
1. Place a water load (150 cc) in the oven.
2. Tap Sensor Reheat pad.
3. Tap Start Pad.
4. Steam Sensor detects steam about 1.5 to 4 minutes after
the Start Pad is tapped.
5. T1 time cooking automatically switches to remaining time
cooking (T2).
6. The remaining cooking time (T2) appears in display
window. If the following cooking time appears, Steam
Sensor function is normal.
7.8. Oven temp sensor thermistor
This sensor monitors the heat produced by the heater circuit
and maintains the oven temperature the user had selected.
Normal room 10°C to 30°C. The reading across the oven
sensor thermistor should be within 100K ohm to 300K ohm
when reading in an area with the 50°F to 90°F room
temperature range.
If the resistance reading is out of the range stated here, the
sensor is detective and must be replaced.
NOTE 1: When measuring resistance disconnect the 3-pin
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NN-V690P / NN-V690PS / NN-V680W / NN-V680W