Instruction manual

Refer figure 4.1b for external resistance programming 0 to 4.85kohms for full
scale voltage and current . It also shows the load connections required in this mode.
As shown in the figure for Voltage Control connect the resistance of 4.85 K ohms at
pin 4 & common control pin 6 of 25 pin D Type connector & for Current control
connect resistance between pin 9 & pin 6 (common control pin) of 25 pin D Type
connector.
4.6.3
Remote ON/OFF:
A 25 pin D type connector & DIP switch is provided for remote analog interface to
the unit. There is 8 pin DIP switch associated with the function of analog interface.
SW no. 8 on the rear 8 pin DIP switch is Remote ON/OFF control & must be always on
for terminal voltage ON when operated from the local controls.
For the remote control keep SW no. 8 OFF and connect switch across pin no. 16 &
17 of 25 pin D type connector.
4.7 OPERATING INSTRUCTIONS IN DIGITAL INTERFACE
To enable remote interface, the command for system to enter remote mode
must be entered through remote P.C. This will cause the remote LED on front panel
to glow; now no key on front panel will be detected. However the display will be
updated to indicate the entered value.
In GPIB interface proper address must be given.
To change the output voltage while working in constant voltage mode operation
or to set the output current while working in constant current mode operation, user
has just to enter command (as specified in chapter 5) through remote PC. There are
simple commands to take the unit either in remote or local mode. The status of the
power supply can be easily read using specific commands. The output can be
turned ON or OFF as per requirements. Output ON is indicated by ON LED on the
front panel. Also the over voltage limit can be set. Whenever the output voltage
exceeds this maximum limit the trip condition occurs thereby resetting the output.
The command summary is given in detail in chapter 5.
4.8
TRIP INDICATIONS
The VSP series power supplies has provision of Over Voltage & Over Tem-
perature protection. If at any time one of these conditions occurs, the unit will be
tripped. This means that the output voltage is made to be zero. This condition is
indicated by the Trip LED blinking.
4.8.1 RESETTING THE TRIP CONDITION
Assess as to why the trip has occurred. Then isolate the fault e.g., over voltage
trip condition can be reset by lowering the output voltage than OV trip level & then
toggling the input power will reset trip condition.
For resetting the over temp condition allow some time for cooling the heat
sinks to change the status of thermal switch.
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