Hitachi P1

Page 18
ELECTRONIC MOTOR THERMAL PROTECTION
The VFD has a built-in utput
current exceeds the value in bC110 
protection function also has the ability to save the current data and calculate it based on output current and time.
Function
Parameters
Value
Electronic thermal level
bC110 Motor FLA * 1.25
Electronic thermal subtraction function
bC112
0 = disabled
1 = enabled
Electronic thermal subtraction time
bC113 600 sec
Electronic thermal counter memory function
bC-14
0 = disabled
1 = enabled
MOTOR THERMAL PROTECTION USING THERMISTOR
The temperature protection of an external device can be made by connecting a thermistor installed in the motor or other external
device to the inverter and setting the function of the thermistor. The external thermistor should be wired between the control
terminals TH+ and TH-. Set the thermistor selection [Cb-40] and the resistance level to cause an error [bb-70] in accordance with the
thermistor’s specifications. When [Cb-40] is set to 02, [dA-38] motor temperature monitor indicates the detected temperature of the
motor.
[E035] thermistor error occurs when the thermistor resistance reaches the thermistor error level [bb-70] depending on the motor
temperature.
To use this function, the wiring distance between the motor and the inverter should be 20 m or shorter. Since the current flowing in
the thermistor is very weak, a measure such as wiring separation should be taken to prevent noise from the motor current.
When [Cb-40] is set to a value other than 02 NTC negative temperature coefficient resistor, [dA-38] motor temperature monitor
indicates 0 °C.
Function
Parameters
Value
Thermistor error level
bb-70 0  10000 ohms
Thermistor selection
Cb-40
0 = disabled
1 = PTC
2 = NTC
Thermistor gain adjustment
Cb-40 
Motor temperature monitor
dA-38 -