QM range App Note, document number 260283, rev 15
Page 11 of 48
DM Modules
Channel 1 and 2 output voltages can be adjusted across the range shown in the
datasheet by using the potentiometer situated to the right of the signal connector.
Channel 1 potentiometer is the upper one, closest to the Channel 1 output
terminals. Turning the potentiometer clockwise increases the output voltage.
Remote sense for Channel 1 and 2 provides compensation for a maximum total
load cable drop of 0.5V for each output. The voltage at the output terminals must
be within the specified adjustment range. See the Remote Sense section in the
POWER SUPPLY OPERATION chapter for connection advice.
To improve the transient load performance, it is recommended that a 120µF, low
ESR, electrolytic capacitor is fitted across the output terminals.
To reduce susceptibility to Electrical Fast Transients, it is recommended that a
120µF, low ESR, electrolytic capacitor is fitted across the output terminals of
channel 2 of the 12/12DM module.
Signals
The CH1 and CH2 Good signals are isolated (200V from each output) opto-coupler transistor outputs. The
maximum current allowed through the transistor is 1mA. These signals provide an indication that each output is
above 90% of the output set voltage. The transistor is on when the output is “good”.
CH2 Good connection shown, use J1-7 & J1-8 for CH2 Good
Module inhibit is an isolated opto-coupler diode input. Passing a minimum of 1mA through the diode will inhibit
(turn off) both outputs of the module.