Hitachi L2002 MOTOR, Thermistor Thermal Protection

4–25

L2002 Inverter

Thermistor Thermal Protection

Motors that are equipped with a PTC 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] at [5] and [L] is more than

3 k Ω ±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

Function Name

Input

Description

Code

Symbol

State

19

PTC

Thermistor Thermal

Sensor

When a thermistor is connected to terminals [5]

Protection

and [L], the inverter checks for over-temperature

and will cause trip (E35) and turn OFF the

output to the motor

Open

An open circuit in the thermistor causes a trip,

and the inverter turns OFF the output

Valid for inputs:

C005 only

Example (requires input configuration—

see page 3–47):

Required settings:

C085

PTC

Notes:

• Be sure the thermistor is connected to terminals [5]

L

5

4

3

2

1

PCS

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.

thermistor

MOTOR

Operations Monitoring and