KEPCO BHK 1000-0.2MG, Operator'S Manual

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BHK-MG (OPR) 032816
3-43
3.6.3.2 CURRENT MODE
With the power supply in current mode (see Figure 3-13 or 3-14) and the digitally programmed
output voltage at zero, varying the low impedance voltage source from 0 to +10V causes the
output current of the power supply to vary linearly from 0 to Iomax with a slope of (0.1 x Iomax)
mA per volt. The following equations give the output current as determined by the low imped-
ance voltage source V
EXT
.
ANALOG PROGRAMMING, DIGITAL PROGRAMMING = 0:
Io = [ (–1) (V
EXT
) x (10K/10K) x (–1) (1K/10K) x (–1) (1K/1K) ]/Rs
= (–1) (0.1/ Rs) x V
EXT
(mA d-c)
= –(0.1/Rs) x V
EXT
(mA d-c)
where
Rs =Internal shunt resistance (K-ohms), determined by Model (see Table 3-10).
(See above for definition of V
EXT
.)
ANALOG PROGRAMMING COMBINED WITH DIGITAL PROGRAMMING:
Io = –(0.1/Rs) x V
EXT
– Iout
DP
(mA d-c)
where
Iout
DP
= Output current programmed digitally (from either local keypad or remote GPIB bus)
(See above for definitions of Rs and V
EXT
.)
3.6.4 PROGRAMMING WITH EXTERNAL VOLTAGE USING A HIGH IMPEDANCE, LOW LEVEL
(1V) VOLTAGE SOURCE
Figures 3-15 and 3-16 are simplified diagrams of the BHK-MG showing the jumper configuration
and external connections required for analog programming using a high impedance, low level
(1V), voltage source. Figure 3-15 shows the configuration for programming of either output volt-
age when the unit is in voltage mode, or voltage limit when the unit is in current mode. Figure 3-
16 is a similar diagrams for programming either output current when the unit is in current mode,
or current limit when the unit is in voltage mode
CAUTION
Observe the following to avoid damage to the power supply. The external voltage source
output must be isolated from ground (floating output), or be powered from an a-c source that is
isolated from ground to avoid short-circuiting the internal sensing resistor.