BENSHAW RediStart MX3 Series, User Manual

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91
6 - PARAMETER DESCRIPTION
Slow Speed Time Limit CFN 25
LCD Display
Range Off, 1 – 900 Seconds (Default 10)
Description The Slow Speed Time Limit parameter sets the amount of time that continuous operation of slow speed may
take place. When this parameter is set to "Off", the timer is disabled. This parameter can be used to limit the
amount of slow speed operation to protect the motor and/or load.
z
NOTE:
The Slow Speed Time Limit includes the time used for the Slow Speed Kick if kick is enabled.
z
NOTE:
The Slow Speed Time Limit resets when the motor is stopped. Therefore, this timer does not
prevent the operator from stopping slow speed operation and re-starting the motor, which can result in the
operation time of the motor being exceeded.
z
NOTE: When the motor is operating at slow speeds, its cooling capacity can be greatly reduced.
Therefore, the running time of the motor at a given current level is dependant on the motor’s thermal capacity.
Although the Motor OL is active (if not set to "Off") during slow speed operation it is recommended that the
motor temperature be monitored if slow speed is used for long periods of time.
See Also Motor Running Overload Class parameter (QST03) on page 73.
Slow Speed Current Level parameter (CFN24) on page 90.
Motor PTC Trip Time (PFN27) on page 104.
Theory of Operation section 7.6, Slow Speed Operation on page 164.
Slow Speed Kick Level CFN 26
LCD Display
Range Off, 100 – 800 % FLA (Default Off)
Description The Slow Speed Kick Level sets the short-term current level that is applied to the motor to accelerate the
motor for slow speed operation. If set to "Off" the Slow Speed Kick feature is disabled. Slow speed kick can
be used to “break loose” difficult to start loads while keeping the normal slow speed current level at a lower
level.
This parameter should be set to a midrange value and then the Slow Speed Kick Time (PFN27) should be
increased in 0.1 second intervals until the kick is applied long enough to start the motor rotating. If the motor
does not start rotating then increase the Slow Speed Kick Level and begin adjusting the kick time from 1.0
seconds again.
If the motor initially accelerates too fast then reduce the Slow Speed Kick Level and/or reduce the Slow Speed
Kick Time.
See Also
Kick Level 1 parameter (CFN11) on page 83.
Slow Speed Kick Time parameter (CFN27) on page 91.
Motor PTC Trip Time (PFN27) on page 104.
Theory of Operations section 7.6, Slow Speed Operation on page 164.
CFN: SSpd Timer
25
10 sec
CFN: SSpd Kick Cu
26
Off