Motor Overheat Protection (Electronic Thermal O/L Relay) - Mitsubishi Electric FR-A820-00046 Instruction Manual

Parameters
5.10.1

Motor overheat protection (electronic thermal O/L relay)

Set the current of the electronic thermal O/L relay function to protect the motor from overheating.
Such settings will provide the optimum protective characteristic considering the low cooling capa-
bility of the motor during low-speed operation.
Pr.
9
H000
600
H001
601
H002
602
H003
603
H004
604
H005
607
H006
51
H010
692
H011
693
H012
694
H013
695
H014
696
H015
608
H016
561
H020
1016
H021
876
H022
For FR-A820-00077(0.75K) or lower and FR-A840-00038(0.75K) or lower, the current is set to 85%
of the rated current.
The setting range for FR-A820-03160(55K) or lower and FR-A840-01800(55K) or lower. The mini-
mum setting increment is "0.01 A".
The setting range for FR-A820-03800(75K) or higher, and FR-A840-02160(75K) or higher. The
minimum setting increment is "0.1 A".
FR-A800
Name
Electronic thermal O/L relay
First free thermal reduction
frequency 1
First free thermal reduction
ratio 1
First free thermal reduction
frequency 2
First free thermal reduction
ratio 2
First free thermal reduction
frequency 3
Motor permissible load level
Second electronic thermal O/
L relay
Second free thermal
reduction frequency 1
Second free thermal
reduction ratio 1
Second free thermal
reduction frequency 2
Second free thermal
reduction ratio 2
Second free thermal
reduction frequency 3
Second motor permissible
load level
PTC thermistor protection
level
PTC thermistor protection
detection time
Thermal protector input
Setting
Initial value Description
range
Inverter
0 to 500 A
rated current
Set the rated motor current.
0 to 3600 A
0 to 590 Hz
9999
9999
1 to 100%
100%
The electronic thermal O/L relay operation level
9999
can be changed to match the motor temperature
0 to 590 Hz
characteristics with the combination of these
9999
three points (Pr. 600, Pr. 601), (Pr. 602, Pr. 603),
9999
(Pr. 604, Pr. 9).
1 to 100%
9999: Free thermal O/L relay invalid
100%
9999
0 to 590 Hz
9999
9999
Set the permissible load according to the motor
150% 110 to 150%
characteristics.
0 to 500 A
Enabled when the RT signal is ON.
Set the rated motor current.
9999
0 to 3600 A
9999 Second electronic thermal O/L relay invalid
0 to 590 Hz
9999
9999
1 to 100%
100%
The electronic thermal O/L relay operation level
9999
can be changed to match the second motor
0 to 590 Hz
temperature characteristics with the
9999
combination of these three points (Pr. 692,
9999
Pr. 693), (Pr. 694, Pr. 695), (Pr. 696, Pr. 51).
1 to 100%
9999: Second free thermal O/L relay invalid
100%
9999
0 to 590 Hz
9999
9999
Set the permissible load when the RT signal is
110 to 150%
ON.
9999
The Pr.607 setting is applied even when the RT
9999
signal is ON.
Set the PTC thermistor protection level
0.5 to 30 kΩ
(resistance).
9999
9999 PTC thermistor protection disabled
Set the time from when the resistance of the PTC
0 s 0 to 60 s thermistor reaches the protection level until the
protective function is activated.
Terminal OH of the control terminal option (FR-
0
A8TP) is invalid.
1
Terminal OH of the control terminal option (FR-
1
A8TP) is valid.
(H) Protective function parameter
5 - 303