OnLine Power Phase Stabilizer - Manual (Page 50)

OnLine Power
6002-032 REV H 3-11
3-1-9 Calibrate Control Logic Board (continued)
DANGER!!
FATAL SHOCK HAZARD!! LETHAL VOLTAGES EXIST WITHIN THE UNIT
DURING THE FOLLOWING CHECK. FOLLOW THE STEPS BELOW
EXACTLY. FAILURE TO DO SO COULD RESULT IN SEVERE INJURY OR
DEATH.
8. Make the following adjustments on the Control logic board for phase A: See Illustration 3-1.
a. Measure AC voltage across R1 or R2. Voltage should be between 10 and 100mv.
b. Measure DC voltage across C42.
c. Adjust R62 until voltage reads 8.5 VDC with a load of 1 kw for 50 kVA or less and 2 kw load for 75 kVA or
larger.
Note
Potentiometer R62 is a 30-turn pot. It may require several turns before output level changes.
d. Adjust R39 counter clockwise until LED 6 is lit. See Illustration 3-1 and Illustration 3-2.
e. Measure DC voltage across C42.
f. Adjust R62 until voltage reads 8.5 V.
g. Measure neutral-to-phase A output voltage between transformer terminals X1 and X0.
Refer to Appendix B for transformer terminal configuration.
h. Adjust R39 until output voltage reads 120V or 277V, phase to neutral, depending on rated output voltage.
• Output voltage should be ± 3% of nominal for Power-Reg and Ultra-Reg
Output voltage should be ± 2% of nominal for Phase Stabilizer
Note
Output voltage does not change linearly as potentiometer R39 is rotated. Output voltage does a
step change. Pot R39 is a 30-turn pot. It may require several turns before output level changes.
i. Repeat the procedure on the phase-B and phase-C Control logic boards. Take voltage measurements
between transformer terminals X2 and X0 and between X3 and X0 respectively for phase B and C.