Rockwell Automation FlexPak Plus NRG DC Drive - Manual (Page 18)

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4.3.3. Minimum Speed (Voltage) - The Minimum
SpeedPotentiometer on the regulator has been factory
preset for drive minimum speed, 5%. By means of adĆ
justment, this speedmay be raisedor lowered. The reĆ
sult is the lowest moving speedthe operator can set on
the SPEED dial. The control range is 5% to 30% of rated
speed.
Again, the motor speedcan be determinedwith a
tachometer.
With the SPEED dial at zero position and using a small,
insulatedslot screwdriver, carefully turn the Minimum
SpeedPotentiometer until the desiredminimum is
reached. Note that CW represents an increase; CCW
represents a decrease.
NOTE: Carefully recheck the maximum speed adĆ
justment for desired setting Since the maximum and
minimum speed adjustments are interactive, a
change in one affects the other. At times, it may be
necessary to work back and forth for precise adjustĆ
ments.
4.3.4 Accelerationand DecelerationRates - The AcĆ
celeration andDeceleration Rate Potentiometers on the
Regulator Module have been factory preset for a typical
linear acceleration rate of six seconds to maximum and
minimum speed. This time can be adjusted over a range
of 0.5 to 30 seconds from a fully stopped condition.
4.3.5 Current Limit - Although it will probably not be
necessary to make any adjustment in the factoryĆset
current limit value of 150% of ratedload, it is possible to
change this governing value. (Individual application
speedchanges or loadchanges on sustainedoverĆ
loads may require readjustment. Also, applications reĆ
quiring torque limiting or accelerating of high inertia
loads may require a change from this value.)
To reduce the torque output of the drive, turn the Current
Limit Potentiometer CCW. Note, however, that turning
CCW too far may prevent the drive accelerating to the
desired speed.
4.3.6 IR Compensation - IR (voltage) Compensation
is a feature which makes up for the armature resistance
of a motor that causes a drop in speedas the loadis inĆ
creased. The IR Compensation Potentiometer is factoĆ
ryĆset at zero. The IR compensation feature can be adĆ
justedbetween O and12% of ratedloadandis used
only for a voltage regulation mode. When using a
tachometer feedback, the IR Compensation PotentiomĆ
eter must be turnedcompletely CCW.
CAUTION: If the IR Compensation Potentiometer
is set too high, motor speedrising characteristics
may result. Instability andoscillation in motor
speedwill result.