56
83503001 Rev G
To preview the OVP setting, press the OVP/UVL pushbutton so that the CURRENT
display will show “OUP”. At this time, the VOLTAGE display will show the OVP setting.
After 5 seconds, the display will return to its previous state.
5.3.2. Activated OVP Protection Indications
When the OVP is activated the power supply output shuts down. The VOLTAGE
display shows “OUP” and the ALARM LED blinks.
5.3.3. Resetting the OVP Circuit
To reset the OVP circuit after it activates:
a) Reduce the power supply Output Voltage setting below the OVP set level.
b) Ensure that the load and the sense wiring are connected properly.
c) There are four methods to reset the OVP circuit.
Press the OUT button.
Turn the power supply Off using the AC On/Off switch, wait until the front panel
display turns Off, then turn the power supply On using the AC On/Off switch.
Turn the power supply output Off and then On using the SO control (refer to
Section 5.7). In this method the power supply should be set to Auto-Restart
mode.
Send an OUT 1 command via the RS232/RS485 communication port.
5.4.
Under Voltage Limit (UVL)
The UVL prevents adjustment of the Output Voltage below a certain limit. The combination
of UVL and OVP functions, allow the user to create a protection window for sensitive load
circuitry.
5.4.1. Setting the UVL Level
Setting the UVL can be made when the power supply output is Enabled (On) or
Disabled (Off). To set the UVL level, press the OVP/UVL button TWICE, so that the
CURRENT meter shows “UUL”. The VOLTAGE meter shows the UVL setting level.
Rotate the VOLTAGE encoder knob to adjust the UVL level. The display will show
‘UUL” and the setting value for 5 seconds after the adjustment has been completed and
then will return to its previous state.
UVL setting values are limited at the maximum level to approximately 95% of the
Output Voltage setting. Attempting to adjust the UVL above this limit will result in no
response to the adjustment attempt. The minimum UVL setting is zero.
5.5.
Foldback Protection
Foldback protection will shut down the power supply output if the load current exceeds the
current limit setting level. This protection is useful when the load circuitry is sensitive to an
overcurrent condition.
5.5.1. Setting the Foldback Protection
To arm the Foldback protection, the FOLD button should be pressed so that the FOLD
LED illuminates. In this condition, transition from Constant Voltage to Constant Current
mode will activate the Foldback protection. Activation of the Foldback protection
disables the power supply output, causes the ALARM LED to blink and displays “Fb” on
the VOLTAGE meter.
