KEPCO BHK-MG Series, Руководство оператора

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3-52
BHK-1/2-MG 030916
3.9.2.1 AUTOMATIC SERIES OPERATION
This operating configuration (see Figure 3-20) is characterized by the fact that each power sup-
ply is independent and must be controlled (programmed) individually, either remotely—via either
the GPIB bus or by analog means—or locally via the keypad. Practical considerations suggest
that the units operate in voltage mode - current limit, controlled from the local keypad. The out-
put voltage and current of the series combination are given by the following equations:
Eo = Eo
A
+Eo
B
Io = Eo / R
LOAD
where
Eo, Io are output values of the series combination (in Volts and milliamperes, respectively)
Eo
A
, Eo
B
are the individual output voltages for two series-connected power supplies (in
Volts)
R
LOAD
is the load value (in K-ohms).
The maximum current delivered by the series combination is dictated by the power supply with
the lowest nominal current and correspondingly, the highest nominal output voltage. For the cur-
rent limit to operate properly, set the desired value of current limit (for the series combination) at
the power supply with the highest nominal output voltage; set the current limit of the other power
supply to a larger value (1% larger or more).
RECOMMENDED PROCEDURE. The following steps are recommended to ensure the combi-
nation of power supplies configured for automatic series operation (power assembly) is properly
connected and set up properly.
1. With the units turned off, perform all external wiring (see Figure 3-20). If possible, use a
properly rated switch between the power supply and the load.
2. Apply power to the units:
a. If a load switch is used, open the switch. Set POWER switch of both units to up position
to turn power on.
b. If load switch is not used, set POWER switch of both units to up position to turn power
on, then press OUTPUT ON/OFF key once on each unit to disable the output.
3. Program Unit A as follows:
NOTE: If using two different BHK models, e.g., 500-80MG and 1000-40MG, unit A must be the
one with the lower current capacity: 1000-40MG
a. Program IsetA to the current limit for the power assembly.
b. Program VsetA to: (to nearest volt) where:
• Eo is the output voltage of the power assembly,
• E
O
maxA is the rated maximum output voltage for unit A (e.g. 500 for the BHK 500-
80MG),
• E
O
maxB is the rated maximum output voltage for unit B.
V s e t E o
E o m a x A
E o m a x A E o m a x B
+
 
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