KEPCO BHK 1000-0.2MG, Руководство оператора

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BHK-MG (OPR) 032816
3-53
ply against a short circuit at the load, with one exception. The current rating of the
reverse-biased diode used on model BHK 2000-0.1MG is 0.2A. When this unit is con-
nected in series with a model BHK 500-0.4MG, which has a maximum current rating of
0.4A, it is necessary to connect an external (reverse-biased) diode across the output of
the 2000V unit which is rated for 3kV reversed voltage and 0.4A direct current.
NOTE: The simplified schematic diagrams (Figures 3-20 through 3-22) illustrating the associ-
ated interconnections show the power supplies configured in either slow mode for units
operating in voltage mode or fast mode for units operating in current mode, however
other combinations are also possible. Due to the low current involved, the units are
shown using local sensing since the drop across the power leads is usually negligible
compared to the output voltage. However, when very precise control of output voltage
applied to the load is desired, remote sensing should be used. Contact Kepco Applica-
tions Engineering when special configurations are indicated.
3.7.2.1 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: