Performance Checks - Lambda LJS-10-V Series Instruction Manual

| PERFORMANCE CHECKS
Check the ripple and regulation of the power supply using the test connection diagram shown in figure
| 9. Use suggested test equipment or equivalent to obtain accurate results. Refer to SPECIFICATIONS AND
| FEATURES for minimum performance standards.
|
|
| Set the differential meter, DC DVM (John Fluke Model 891A or eguivalent) to the selected power sup-
| ply operating voltage. Check the power supply load regulation accuracy while switching from the no load to
¡load condition. Long load leads should be a twisted pair to minimize AC pick-up.
Use a Variac to vary the line voltage from 187-265 or 265-187 volts AC and check the power supply
line regulation accuracy on the DVM differential meter.
Use a VTVM John Fluke Model 931B or eguivalent, to measure rms ripple voltage of the power sup-
ply DC output. Use oscilloscope to measure peak-to-peak ripple voltage of the power supply DC output.
| ADJUSTMENT OF CALIBRATION CONTROLS VR2, VR3
|
| Whenever voltage and current indications do not reflect maximum ratings, adjust VR2 and VR3 as
| follows. The adjustment procedure reguires that the power supply is removed from associated eguipment,
„is at an ambient temperature of 25-30°C, and is stabilized and not operating.
1. Remove AC input power to the supply.
2. Break seal on wiper of VR3 from resistor housing and turn to full CCW position.
3. Operate power supply for constant voltage with local sensing connected as shown in figure 3, with
no external load, and with AC input of 200 VAC, 50 Hz.
4. Turn voltage adjust control until minimum rated output voltage is obtained.
5. Apply load so that output current is 110-115% of 50°C rating for the unit.
6. Using a differential meter, DC DVM (John Fluke Model 891A or eguivalent), observe output volt-
age while adjusting VR3 in CW direction. Adjust УЕЗ until output voltage drops.
7. Remove AC power input to the supply.
8. Break seal on wiper of VR2 from resistor housing.
9. Operate power supply for constant voltage with remote sensing connected as shown in figure 4,
with AC input 200 VAC, 50 Hz.
10. Adjust VR1 to the same operating point as described above.
11. Repeat steps 3 through 10 until no further adjustment is reguired.
12. After adjustment is completed, remove AC input power to the supply and reseal wipers of VR 2
and VR3.
IM-LJS-10-V 11