Selection Of Restart Operation (Pr.162); Restart Coasting Time (Pr.57); Adjustment Of Restart Operation (Pr.611) - Mitsubishi Electric FR-F800 Instruction Manual

Selection of restart operation (Pr.162)
Instantaneous (power failure) time
Power supply
(R/L1,S/L2,T/L3)
Motor
speed N (r/min)
Inverter output
∗
frequency f (Hz)
Inverter output
voltage E (V)
Speed
Coasting
detection
+
time (Pr.57)
time
∗ The output shut off timing sdiffers
according to the load condition
NOTE
• Because a DC injection brake is applied instantaneously at speed detection during a restart, the speed might drop if the
moment of inertia (J) of the load is small.
• Restart operation with reduced voltage is not available for PM motor control.
Restart coasting time (Pr.57)
• The coasting time is the time up till detection of the motor speed and start of restart control.
• To enable restart operation, set "0" (no coasting time) in Pr.57 Restart coasting time. Generally, this setting does not
interfere with inverter operation.
• Inverter operation is sometimes hindered by the size of the moment of inertia (J) of the load or running frequency. Adjust
this coasting time within the range 0.1 s to 30 s to match the load specification.
Adjustment of restart operation (Pr.611)
• Using Pr.611, the acceleration time to reach Pr.20 Acceleration/deceleration reference frequency after a restart
operation can be set. This can be set individually from the normal acceleration time.
NOTE
• Changing the Pr.21 Acceleration/deceleration time increments setting does not affect the Pr.611 setting increment.
• A PM motor is a motor with interior permanent magnets. Regression voltage is generated when the motor coasts at an
instantaneous power failure or at a flying start. The inverter's DC bus voltage rises if the motor coasts fast or makes a flying
start in this condition.
When using the automatic restart after instantaneous power failure function (Pr.57  "9999"), it is recommended to also use
the regenerative avoidance function (Pr.882 Regeneration avoidance operation selection = "1") to make startups stable. If
the overvoltage protective function (E.OV[]) still occurs with the regeneration avoidance function, also use the retry function
(Pr.67).
• During PM motor control, the automatic restart after instantaneous power failure function operates only when an MM-EFS/
MM-THE4 IPM motor is connected
When a regeneration unit is used, the frequency search may not be available if the rotation speed is about 10% higher than
the rating.
Caution
 An IPM motor is a motor with interior permanent magnets. High voltage is generated at motor
terminals while the motor is running.
Do not touch motor terminals and other parts until the motor stops to prevent an electric shock.
 When the automatic restart after instantaneous power failure function is selected, the motor
suddenly starts (after reset time passes) when an instantaneous power failure occurs.
Stay away from the motor and machinery.
Apply the supplied CAUTION stickers to easily visible places when automatic restart after
instantaneous power failure has been selected.
Parameters referred to
Pr.13 Starting frequency page
Pr.65, Pr.67 to Pr.69 retry function
Pr.78 Reverse rotation prevention selection
Pr.178 to Pr.189 (input terminal function selection)
Pr.882 Regeneration avoidance operation selection
• At a power restoration, the encoder detects the motor speed by a
frequency search so that the inverter can re-start smoothly.
• The encoder also detects the rotation direction so that the inverter
can re-start smoothly even during the reverse rotation.
• When "10 (11, 12, 13)" is set in Pr.162, a restart operation is
performed at each start and automatic restart after instantaneous
power failure. When "0 (1, 2)" is set to Pr.162, a restart operation is
performed at the first start after a power-ON, and from the second
power-ON onwards, a start from the starting frequency is performed.
Acceleration time
at a restart
(Pr.611 setting)
197, page 198
page 236
page 217
page 329
page 514
(A) Application parameters
PARAMETERS
5
GROUP
A
421