KB Electronics KBVF-48 - Manual (Page 24)

on page 24.
13.3 ACCELERATION (ACC) – Sets the amount of time for the motor to
accelerate from zero speed to full speed. The ACC Trimpot is factory
set to 1.5 seconds. For longer acceleration time, rotate the ACC
Trimpot clockwise. For more rapid acceleration, rotate the ACC
Trimpot counterclockwise. See Figure 32.
Note: Rapid acceleration settings may cause the current limit circuit
to activate, which will extend the acceleration time.
13.4 DECELERATION (DEC/B) – Sets the amount of time for
the motor to decelerate from full speed to zero speed. The
DEC/B Trimpot is factory set to 1.5 seconds. For longer
deceleration time, rotate the DEC/B Trimpot clockwise. For
more rapid deceleration, rotate the DEC/B Trimpot counter-
clockwise. See Figure 33.
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 ACC and DEC/B
Trimpots should be set to greater than 10 seconds.
For rapid stopping, install the optional DBVF – Dynamic
Brake Module (Part No. 9598). See Section 3.5, on page 10.
13.5 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 34.
The slip compensation may be adjusted as follows:
1. Wire an AC RMS ammeter in series with one motor
phase.
2. Run the motor and set the unloaded speed to approxi-
mately 50% (900 RPM on 4-pole 1500/1725 RPM
motors).
3. Using a tachometer, record the unloaded speed.
4. Load the motor to the nameplate rated current (AC
Amps).
5. Adjust the COMP Trimpot until the loaded RPM is equal to
the unloaded RPM.
6. The motor is now compensated to provide constant speed under varying loads.
24
MAX
- +
ADJUST
FIGURE 31 – MAXIMUM
SPEED TRIMPOT
MODELS KBVF-45, 48
(Shown Factory Set to 1.5 Seconds)
1.5
.3
3
ACC
20
10
17
FIGURE 32 – ACCELERATION
TRIMPOT RANGE
ALL MODELS
(Shown Factory Set to 1.5 Seconds)
1.5
.3
3
DEC/B
20
10
17
FIGURE 33 – DECELERATION
TRIMPOT RANGE
ALL MODELS
(Shown Factory Set to 1.5 Volts/Hz)
COMP
0 3
.8
1.5
2.3
FIGURE 34 – SLIP COMPENSATION
TRIMPOT RANGE
ALL MODELS