KEPCO BHK-MG 200W (Full Rack) Series - Manual (Page 96)

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BHK-MG (OPR) 022014
ble or larger than the internal C
OUT
, it is advisable to connect the internal C
OUT
across
the output by installing the link between terminals TB1-6 and TB1-7, in order to
increase the main feedback capacitance.
CAUTION
Isolate all external circuitry connected to the ungrounded (“live”) output terminal of the power
supply; isolation should be rated to more than maximum output voltage.
3.7.2 SERIES OPERATION
Kepco BHK-MG power supplies can be series-connected to increase output voltage if the pre-
cautions outlined below are followed. Two basic series-connection methods are generally used:
automatic (PAR. 3.7.2.1) and master-slave (PAR. 3.7.2.2).
HANDLING HIGH VOLTAGE, LOW IMPEDANCE EQUIPMENT IS DANGEROUS, AND
POTENTIALLY LETHAL. OBSERVE ALL PRECAUTIONS LISTED IN PAR. 3.6.1., AS WELL
AS THE PRECAUTIONS LISTED BELOW.
a. Do not exceed the specified isolation voltage limit (see Table 1-2). If the isolation volt-
age might be exceeded, limit the excursion of one power supply output: e.g., if two
BHK 2000-0.1MG models are to be series-connected, the output of one must be
restricted to 0.5 kV (limiting the series combination to a maximum of 2.5kV), because
the isolation voltage for this model is 2kV + 0.5kV (see Table 1-2).
b. Connect the chassis ground terminal, TB1-4, of all series-connected power supplies to
a good a-c ground (earth ground).
c. If necessary, the grounding network can be used for each one of the series-connected
power supplies within the limits of the maximum isolation voltage (see Table 1-2) of the
Model BHK-MG Series (refer to PAR. 2.7.5.3 for additional information regarding use of
the grounding network).
d. The series combination of BHK-MG power supplies can operate either isolated from
ground (floating) or with either of the two output terminals of the series combination
grounded. When analog programming is used, however, it is recommended that the
positive output terminal of the series combination be grounded to avoid potentially haz-
ardous conditions requiring the use of fully insulated external equipment (see precau-
tions of PAR. 3.6.1).
If the negative output terminal is grounded, special precautions are required when using
external programming sources: THE PROGRAMMING SOURCE MUST BE ISOLATED AND
INSULATED for the sum of the voltages of the series combination. The programming source
must be either battery powered or powered through an isolation transformer and have “fully
insulated controls and chassis” features (see also PAR. 3.6.1).
e. Each BHK-MG power supply contains an internal, reverse-biased diode across the out-
put which protects the power supply by limiting the opposite polarity voltage at the out-
put. This diode is rated for the nominal output voltage of each model (see Table 1-1).
When BHK-MG power supplies are series-connected, this diode will protect each sup-
WARNING