Over Power Protection (Opp); Over Temperature Protection (Otp); Reverse Voltage Protection (Lrv); Key Lock Function - ITech IT8500plus Series User Manual

3.17.3 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] >
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 off, VFD will display OPP.
Operations to Clear the OPP State
Disconnect the instrument under test. Press any key on the front panel, the
OPP
state.

3.17.4 Over Temperature Protection (OTP)

If internal temperature exceeds safety limits(85℃ ;185 °F), the Over
temperature circuitry will be activated. The DC Load will turn off 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
load exits OTP protection state.

3.17.5 Reverse Voltage Protection (LRV)

This feature protects the DC load in case the DC input terminals are connected
to a power source with reversed polarity. If a reverse voltage condition is
detected, the buzzer will sound and will be displayed on the VFD.
Operations to Clear the Reverse Voltage State
Check whether the connection is reversed; if so disconnect the power source.

3.18 Key Lock Function

Press [Shift] +[On/Off] (Lock)key to lock the front panel keys,VFD will display
a Lock
not be changed.Press [Shift] +[On/Off] (Lock)again will disable this function.

3.19 The Terminals on the Rear Panel

3.19.1 Remote Sensing

Remote sensing is used to counteract the effect of lead resistance.
example, if you connect a power supply to the DC Load, the voltage at the
power supply's terminals will not be the same as the voltage at the DC Load's
terminals if there is a current flowing because of the finite resistance from the
wires. Using remote sensing, you can sense the voltage at the power supply's
terminals, effectively removing the effect of the voltage drop in the connection
wire.
When using remote sensing, the power displayed by the instrument includes
both the power dissipated inside the instrument and the power dissipated in the
Protect > P-LIMIT > P-LIM POIN
displayed on the VFD will disappear, the DC load exits OPP protection
OTP) displayed on the front panel will disappear, the DC
label.In this state,setting values can not be modified,woriking mode can
Copyright © Itech Electronics Co., Ltd.
Functions and Characteristics
set OPP power value, P-LIM DELAY
For
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