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Figure 7-4 Deceleration Trimpot Range
(Shown Factory Set to 1.5 Seconds)
Application Note:
On applications with high inertial loads, the
deceleration may automatically increase in time. This will slow down the
rate of speed of decrease to prevent the bus voltage from rising to the
Overvoltage Trip point. This function is called Regeneration Protection. It
is recommended that for very high inertial loads that both the ACCEL and
DECEL Trimpots be set to greater than 10 seconds.
7.5 SLIP COMPENSATION (COMP)
Sets the amount of Volts/Hz to maintain set motor speed under
varying loads. The COMP Trimpot is factory set to 1.5 Volts/
Hz, which provides excellent speed regulation for most motors.
To increase the slip compensation, rotate the COMP Trimpot
clockwise. To decrease the slip compensation, rotate the COMP
Trimpot counterclockwise. See Figure 7-4.
Figure 7-5 Slip Compensation Trimpot Range
(Shown Factory Set to 1.5 Volts/Hz)
The slip compensation may be adjusted as follows:
A. Connect an AC RMS ammeter in series with one motor phase.
B. Run the motor and set the unloaded speed to approximately 50% (900
RPM on 4-pole 1500/1725 RPM motors).
C. Using a tachometer, record the unloaded speed.
D. Increase motor loading until motor current is equal to the nameplate
rated current (AC Amps).
E. Adjust the COMP Trimpot until the loaded RPM is equal to the
unloaded RPM.
The motor is now compensated to provide constant speed under
varying loads.
Summary of Contents for NEMA 1 / IP40
Page 18: ...18 Figure 2 3 Drive Layout...
