Mitsubishi Electric FR-A800, Instruction Manual

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(H) Protective function parameter Parameters
5 - 322
5.10.12 Motor overspeeding detection
The Overspeed occurrence (E.OS) is activated when the motor speed exceeds the overspeed detec-
tion level. This function prevents the motor from accidentally speeding over the specified value, due
to an error in parameter setting, etc.
The motor maximum frequency is set in Pr. 702 "Maximum motor frequency." When Pr. 702 = "9999
(initial value)", the Pr. 84 "Rated motor frequency" setting is applied as the motor maximum
frequency.
Parameters referred to
Pr. 22 Torque limit level => page 5-84
Pr. 73 Analog input selection => page 5-389
Pr. 178 to Pr. 189 (Input terminal function selection) => page 5-422
Pr. 190 to Pr. 196 (Output terminal function selection) => page 5-361
Pr. 858 Terminal 4 function assignment => page 5-394
Pr. 868 Terminal 1 function assignment => page 5-394
Pr. Name
Initial
value
Setting
range
Description
374
H800
Overspeed detection level 9999
0 to 590 Hz
If the motor rotation speed exceeds the speed set in
Pr. 374 during encoder feedback control, Real
sensorless vector control, vector control or PM
sensorless vector control, Overspeed occurrence (E.OS)
occurs, the inverter output is shut off.
9999
If the speed exceeds "the maximum speed (Pr. 1, Pr. 18)
+ 20 Hz" during encoder feedback control, Real
sensorless vector control, or vector control, E.OS
occurs.
During PM sensorless vector control, E.OS occurs when
the speed exceeds "the motor maximum fre
10 Hz"
Fig. 5-145:
Overspeed detection level and alarm occurrence
I002601E
NOTE During encoder feedback control and vector control, the motor speed is compared against Pr. 374.
During Real sensorless vector control and PM sensorless vector control, the output frequency is
compared against Pr. 374.
ALM
E.OS
Motor speed
Pr. 374
Coast to stop
ON
Time