JVC 330 Service Manual page 112

Chapter 3---Service Adjustments
2. Measure the number of millivolts between pins 3 and 4 on SPS J505.
NOTE: This circuit is designed so that the number of millivolts between
these pins (for Models 340 and 370, it is millivolts divided by 10)
represents the lamp current in amps.
3. Multiply the two (2) figures from Item 1 and from Item 2 together.
4. Divide the product from Step 3 by 1 for Model 330 wattage. Divide the
product from Step 3 by 10 to get wattage for Model 340SC or 370SC.
5. Adjust the Lamp Current Adjust pot (see CAUTION below Table 3-1) on
the top of the SPS (refer to Figure 4-3) until this result is within the
appropriate HJT model spec indicated in Table 3-1).
Example (for Model 370SC): Voltage measured between J503 and
J504 = 28V and voltage measured between pins 3 and 4 of J505 =
1070mv.
The product of this is 29960÷10 = 2996W. This result is within the Model
370SC spec of 3000W ± 25W and would not require adjustment.
Table 3-2 Arc Lamp Current and Amp Specs
Model 330
1500 Watts ± 25W
68 Amps Normal
70 Amps Maximum
CAUTION!
integrity (lamp overheating may occur if current is abruptly increased). Do not
increase the current beyond the maximum levels listed in Table 3-2.
3-22
Model 340SC
2000 Watts ± 25W
80 Amps Normal
85 Amps Maximum
Make adjustments in small increments to ensure lamp
Model 330, 340SC, 370SC Service Manual
Model 370SC
3000 Watts ± 25W
100 Amps Normal
110 Amps Maximum