User Manual
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(system)——RUNMODE—- ——select “NORMAL” mode—- .
8.5.18 Overvoltage Protection (OVP)
The instrument’s maximum OVP limit is 110% of the maximum rated voltage.
If the OVP circuit has triggered, input will turn o, buzzer alarm will go o, and the status register’s OV and VF bit will
be set. The mainframe will display OVP and the condition will remain until they are reset. Once over-voltage protection
occurs, the “VF” pin on the rear panel will output TTL Low voltage level. Under normal conditions, it outputs a 5 V
TTL high signal.
Operations to Clear the OVP State
Check whether the input voltage is within the electronic load’s rated voltage or the programmed protection voltage ranges.
If it is outside the range, please disconnect the device under test. Then press any key on the front panel or remotely send
SCPI command
PROTection:CLEar. The OVP displayed on the front panel will turn o and the electronic load exits OVP protection
state.
8.5.19 Over-temperature Protection (OTP)
There is an overtemperature protection circuit, which will turn o the input if the internal temperature exceeds safe
limits. When the electronic load’s internal circuit temperature is over
85C, the load will enable OTP. Input will automatically be turned o and the VFD will display OTP. At the same time
the OT and PS bits in the status register will be set and remain until they are reset.
Operations to Clear the OTP State
When the electronic load temperature has dropped below the protection point, press any key on the front panel or
remotely send command PROTection:CLEar. The OTP displayed on the front panel will turn o and the electronic load
exits OTP protection state.
8.5.20 Reverse Voltage Protection (LRV/RRV)
This function protects the electronic load in case the input DC voltage lines are connected with the wrong polarity. When
a reverse voltage (LRV – local reverse voltage, RRV – remote reverse voltage) connection condition is detected, the input
will immediately turn o, the buzzer will alarm the user, and the status register’s reverse voltage (LRV/RRV) and VF
bits will be set. The load will display LRV/RRV until they are reset.
In this condition, the “VF” pin will output a low level.
Operations to Clear the Reverse Voltage State
Check whether the connection is reversed. If so, disconnect the device to be measured and the reverse voltage state will
be cleared.
8.5.21 Congure Timed Input
The load has a built-in timer function that is congured to allow enabling (ON) the main input for a specied amount
of time. To congure this time, follow the steps below:
1. Go to “CONFIG” menu and select “Protect”. Then press .
2. Select “Time” and press .
3. To enable timed input, select “On” and press . The default is “O”.