Electronic Thermal Overload Alarm Setting - Hitachi WJ200 Series Instruction Manual

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Electronic Thermal Overload Alarm Setting

The thermal overload detection protects the inverter and motor from overheating due to
an excessive load. It uses a current/inverse time curve to determine the trip point.
First, use B013 to select the torque characteristic that matches your load. This allows
the inverter to utilize the best thermal overload characteristic for your application.
The torque developed in a motor is directly proportional to the current in the windings,
which is also related to the heat generated (and temperature, over time).
Therefore, you must set the thermal overload threshold in terms of current (amperes)
for parameter B012. The range is 20% to 100% of the rated current for each inverter
model. If the current exceeds the level you specify, the inverter will trip and log an event
(error E 05) in the history table. The inverter turns the motor output OFF when tripped.
Separate settings are available for the second motor (if applicable) as shown in the
following table.
Func.
Code
Level of electronic thermal
B012
Level of electronic thermal,
B212
2 motor
nd
Electronic thermal
B013
characteristic
Electronic thermal
B213
characteristic, 2
Free setting electronic
b015
thermal ~freq.1
Free setting electronic
b016
thermal ~current1
Free setting electronic
b017
thermal ~freq.2
Free setting electronic
b018
thermal ~current2
Free setting electronic
b019
thermal ~freq.3
Free setting electronic
b020
thermal ~current3
WARNING: When parameter B012, level of electronic thermal setting, is set to motor
FLA rating (Full Load Ampere nameplate rating), the inverter provides solid state
motor overload protection at 115% of motor FLA or equivalent. If parameter B012
exceeds the motor FLA rating, the motor may overheat and be damaged. Parameter
B012, level of electronic thermal setting, is a variable parameter.
"b" Function
Name
Set a level between 20% and 100%
for the rated inverter current.
Select from three curves, option
codes:
00...Reduced torque
01...Constant torque
02...Free setting
motor
nd
Range is 0 to 400Hz
Range is 0 to inverter rated current
Amps
Range is 0 to 400Hz
Range is 0 to inverter rated current
Amps
Range is 0 to 400Hz
Range is 0 to inverter rated current
Amps
Description
Run Defaults
Mode
Lnitial data Units
Edit
Rated A
current for
each
inverter
model *1
A
01 −
01 −
0.0 Hz
0.00 Amps
0.0 Hz
0.00 Amps
0.0 Hz
0.00 Amps