KB Electronics KBVF-23P - Manual (Page 40)

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 13.
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 com-
pensation, rotate the COMP Trimpot clockwise. To decrease
the slip compensation, rotate the COMP Trimpot counterclock-
wise. See Figure 26.
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 approximately
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 (Amps AC).
40
17 3
(Shown Factory Set to 1.5 Seconds)
Seconds
.3
1.5
20
10
FIGURE 25 – DECELERATION
TRIMPOT (DEC/B) RANGE
2.3 .8
(Shown Factory Set to 1.5 Volts/Hz)
Volts/Hz
0 3
1.5
FIGURE 26 – SLIP COMPENSATION
TRIMPOT (COMP) RANGE
(Shown Factory Set to 5 Volts/Hz)
5
Volts/Hz
0 30
8
15
23
FIGURE 27 – BOOST TRIMPOT
(DEC/B) RANGE