BEHLMAN BL20000 Series, Руководство пользователя и техническое руководство

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15
BL20K SERIES REV E 2013
3.5 EXTERNAL SYNC ( continued )
!
CAUTION
The external sync signal applied to the unit must not be lower than 45 Hz to avoid possible damage to
the unit. It is also recommended that load be de-energized and the output voltage of the power supply
be set to zero before connecting a sync signal. This will prevent potentially damaging transients from
reaching the load.
3.6 ADJUSTMENT OF LINE DROP COMPENSATION
The line drop compensation trim pots on the power source front panel allows the user to compensate
for resistive loses in the load wiring. One trimmer is provided for each of the three output phases. And
external voltmeter with 0.1V resolution is required to properly set this trimmer.
Always use a non-
metallic screwdriver for this adjustment.
1.) With the Unit on and stabilized, note the voltage indication on the front panel meter for phase A . Apply
the desired load and use an external voltmeter (as close to the load as practical) to measure the voltage
supplied to the load terminals A and Neutral.
2.) Using an insulated screwdriver, adjust the front panel “LINE DROP COMP” to bring the load terminal
voltage to the same value as that indicated by the front panel voltmeter. This will compensate for I/R
drops due to the load wiring. Note, Line drop comp will not work without a load applied.
3.) Repeat steps 1 and 2 for the remaining phases.
3.7 PHASE ADJUSTMENT
! CAUTION
MIS-ADJUSTING PHASE ANGLES CAN CAUSE A LARGE IMBALANCE IN DELTA CONNECTED
LOADS AS THE LINE TO LINE VOLTAGE ARE AFFECTED. DO NOT ATTEMPT TO ADJUST
PHASE UNLESS THE IMPACT ON THE LOAD IS UNDERSTOOD.
Two front panel trim controls are provided for phase angle adjustment. To adjust the phase shift
between two phases, proceed as follows:
USE NON METALLIC SCREWDRIVER .
1) Connect an external DVM between N
A and
N
B on the output terminal strip.
2) Turn on circuit breaker and output switch and adjust output to 100 VRMS.
3) To produce a phase shift between phase A and phase B, adjust phase difference between N A - N B until
external DVM indicates the Vrms value required to produce the desired phase angle. Use the table below
as a guide. It shows five predetermined values. For in-between phase angles, use the formulas shown.
DVM Phase V = [(1-cos N ) 20,000] ½
(Vrms) Angle(°) N = cos
-1
[1-V
2
/20,000]
81.3 48 where V = Vrms setting on DVM
100.0 60 and
N
= phase angle desired
141.4 90
173.2 120
190.2 144
4) Connect DVM across N B and N C and repeat and adjust N B - N C trimmer for the desired phase shift
between phases B & C .