User Manual

“Step Delay” This is the delay time to hold each power step in the test. This determines how fast or

slow to run through the test.

“End Power” This is the ending power value before OPP test ends. The test will only run through in steps from

“Start Power” to the “End Power” if input voltage is greater than the “OPP Voltage”.

“OPP Voltage” This value is a limit that is used to test for OPP conditions. In the event of an over power

condition, when the input voltage is greater than this value, the test will run through from “Start

Power” to “End Power” in steps. The input power (the over power) value will be checked during

this process. If power is within the “Max Trip Power” and “Min Trip Power” boundaries, the load

will indicate “Pass” at the end of the test. If outside of these boundaries, the load will indicate

“Fault”.

“Max Trip Power” The maximum acceptable power limit of the over power value.

“Min Trip Power” The minimum acceptable power limit of the over power value.

Operations to clear the OVP state

Disconnect the instrument under test. Press any key on the front panel, the OVP on the VFD will disappear, then the

DC load exits OVP protection state.

5 Over Current Protection (OCP)

The DC load includes both hardware and software over current protection features.

Hardware OCP: maximum input current of the DC load will be limited at about 110% of the current range, once the

hardware OCP is activated, the status register’s OC bit will be set; when the hardware OCP is removed, the status

Software OCP: users can set the DC load’s software OCP value, steps:

[Shift] + [9] > Protect > Alimit set ON, Apoint set OCP current value, Adelay set delay time before alarm. When the

software OCP function is active, the DC load will automatically turn o, VFD displays OCP.

Operations to clear the OCP state

Disconnect the instrument under test. Press any key on the front panel, the OCP displayed on the VFD will disappear,

the DC load exits OCP protection state.

6 Over Power Protection (OPP)

The DC load includes both hardware and software OPP features.

Hardware OPP: the DC load allows user to set a power protection limit in hardware which will limit the power in the

range you set when the OPP occur. The hardware OPP protection will not change the ON/OFF state of the the DC

load.

Software OPP: users can set the DC load’s software OPP value, steps: [Shift] +[9] > Protect > P-LIMIT > P-LIM

POINT set OPP power value, P-LIM DELAY set alarm delay. If the the DC load’s power value reach OPP limit and

after the delay time, the DC load will automatically turned o, VFD will display OPP.

Operations to Clear the OPP State

Disconnect the instrument under test. Press any key on the front panel, the OPP displayed on the VFD will disappear,

the DC load exits OPP protection state.

7 Over Temperature Protection (OTP)

If internal temperature exceeds safety limits(85C ;185F), the Over temperature circuitry will be activated. The DC Load

will turn o the input, the buzzer will sound, and the display will show OTP.

Operations to Clear the OTP State

When the DC load temperature drops to the protecting point, press any key on the front panel, the OTP) displayed on

the front panel will disappear, the DC load exits OTP protection state.