Protection
The output has intrinsic short-circuit protection and is protected from reverse voltages by a diode;
the continuous reverse current must not exceed 3 Amps, although transients can be much higher.
In common with all series regulated single-ended power supplies, the unit is not capable of
sinking current provided from an external source.
If a voltage greater than the set output voltage of the unit is applied from an external source, the
internal regulator will turn off, no current will flow, and the voltage meter will read the applied
voltage. No damage will result providing the applied voltage does not exceed the maximum
output voltage of the power supply by more than 20 Volts. Application of a voltage greater than
this is prohibited.
Remote Sensing
The unit has a very low output impedance, but this is inevitably increased by the resistance of the
connecting leads. At high currents this can result in significant differences between the indicated
source voltage and the actual load voltage (two 20mΩ connecting leads will drop 0.2V at 5 Amps,
for instance). This problem can be minimised by using short, thick, connecting leads, but where
necessary it can be completely overcome by using the remote sense facility.
This requires the sense terminals to be connected to the output at the load instead of at the
source; insert wires into the spring-loaded SENSE terminals and connect directly to the load.
Switch the LOCAL/REMOTE switch to REMOTE. To avoid instability and transient response
problems, care must be taken to ensure good coupling between each output and sense lead. This
can be done either by twisting the leads together or by using coaxially screened cable (sense
through the inner). An electrolytic capacitor directly across the load connection point may also be
beneficial.
The voltage drop in each output lead must not exceed 0.5 Volts.
Switch the LOCAL/REMOTE switch back to LOCAL when remote sensing is not in use.
Output Voltage
The output voltage can be set between 1.5V and 5.0V using the front panel rotary adjustment
beside the centre terminals. With the right-hand main output OFF, pressing the SHOW AUX
PRESET button will display the AUX output voltage and current limit on the right-hand meters.
Current Limit
The output will go into current limit above 2A; the UNREG lamp lights in this condition.
Protection
The output has intrinsic short-circuit protection and is protected from reverse voltages by a diode;
the continuous reverse current must not exceed 3 Amps, although transients can be much higher.
The output is protected against external forward voltages up to 16 Volts.
Operation – Auxiliary Output
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