Turbo Chef Technologies i5 service manual Testing a High-Voltage Diode, Oven Systems

High Voltage Transformers	Primary Voltage, Frequency, Taps,		Secondary Taps and Resistance
	and Resistance
NGC-3062-1	208	VAC, 60 Hz, 1 & 2,	4, Ground, 53.60–65.52 W
	0.819–1.001 W
	240	VAC, 60 Hz, 1 & 3,
	0.972–1.188 W
NGC-3062-2	230	VAC, 50 Hz, 1 & 2,	3, Ground, 57.52–70.30 W
	0.972–1.188 W
NGC-3062-3	200	VAC, 50/60 Hz, 1 & 2,	3, Ground, 55.75–68.13 W
	0.784–0.958 W
Filament Transformers	Primary Voltage, Frequency, Taps,		Secondary Taps and Resistance
	and Resistance
NGC-3061-1	208	VAC, 60 Hz, 1 & 2,	4, 5, very low resistance - if read-
	17.49–21.37 W		ing is open, transformer has failed.
	240	VAC, 60 Hz, 1 & 3,
	20.61–25.19 W
NGC-3061-2	230	VAC, 50 Hz, 1 & 2,	3, 4, very low resistance - if read-
	18.99–23.21 W		ing is open, transformer has failed.
NGC-3061-3	200	VAC, 50/60 Hz, 1 & 2,	3, 4, very low resistance - if read-
	15.70–19.18 W		ing is open, transformer has failed.

High Voltage and Filament Transformer Resistance Table

31

When the high-voltage winding starts to go toward negative, the high-voltage diode becomes non- conducting with the charged high-voltage capacitor in series with the high-voltage winding. When the transformer gets to its negative peak of -2400 VPK, the voltage applied to the filament is negative 4500 volts. The high-voltage diodes are rated at 16 kVDC.

Testing a High-Voltage Diode

DANGER: Never attempt to measure high voltage directly. Death or serious injury could result.

1. Disconnect the oven from the power source.

2.Fully discharge the capacitors.

3.Connect the voltage meter in series with diode.

4.Using a multimeter set to DC voltage, connect one meter lead to one side of a 9-volt battery and the other lead to one side of the diode.

5.Connect the other side of the 9-volt battery to the other side of the diode. DC voltage should only be present on the meter in one direction.

6.Switch the meter leads on the diode, which will cause the opposite reading to be visible. Depending on the voltage of the battery, voltage between 5-7 VDC should be present in only one direction and 0-0.1 VDC in the other direction.

OVEN SYSTEMS