Thermistor Thermal Protection - Hitachi WJ200 Series Instruction Manual

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Thermistor Thermal Protection

Motors that are equipped with a thermistor can be protected from overheating. Input
terminal [5] has the unique ability to sense a thermistor resistance. When the
resistance value of the thermistor connected to terminal [PTC] (5) and [L] is more than
3 kΩ ±10%, the inverter enters the Trip Mode, turns OFF the output to the motor, and
indicates the trip status E35. Use this function to protect the motor from overheating.
Option Terminal
Code Symbol
PTC
19
Valid for inputs:
Required settings
Notes:
• Be sure the thermistor is connected to terminals
[5] and [L]. If the resistance is above the threshold
the inverter will trip. When the motor cools down
enough, the thermistor resistance will change
enough to permit you to clear the error. Press the
STOP/Reset key to clear the error.
Function Name State
Thermistor Thermal
Protection
C005 only
(none)
ON When a thermistor is connected to terminals [5] and
[L], the inverter checks for over-temperature and will
cause trip (E35) and turn OFF the output to the
motor
OFF An open circuit in the thermistor causes a trip, and
the inverter turns OFF the output
Example (requires input configuration—
see page 3–84):
PTC
7 6 5
Description
4 3 2 1 L P24
PLC PCS
Thermistor