KEPCO BHK-MG 200W (Full Rack) Series - Manual (Page 85)

BHK-MG (OPR) 022014
3-41
FIGURE 3-14. ANALOG PROGRAMMING OF OUTPUT CURRENT (CURRENT MODE) OR CURRENT
LIMIT (VOLTAGE MODE) USING GROUNDED LOW IMPEDANCE VOLTAGE SOURCE (VS)
The external voltage source is applied to the input of the uncommitted amplifier which is config-
ured either as an inverting repeater (Figures 3-11 and 3-13) for isolated voltage sources or a dif-
ferential amplifier having a gain of –1 (Figures 3-12 and 3-14) for grounded voltage sources.
The positive voltage is applied to the inverting input of the uncommitted amplifier referenced to
internal signal ground. The voltage source impedance should be low compared to the 10K input
impedance into the programming terminals of the power supply.
CAUTION
Observe the following to avoid damage to the power supply. For isolated voltage sources
(Figures 3-11 and 3-13), the external voltage source output must be isolated from ground (float-
ing output), or be powered from an a-c source that is isolated from ground to avoid short-circuit-
ing the internal sensing resistor,. If neither of these options are practical, use the grounded
voltage source configurations shown in Figures 3-12 and 3-14.