KB Electronics KBRC-240D - Manual (Page 19)

VIII. TRIMPOT ADJUSTMENTS
The KBRC-240D contains trimpots which are factory set for most
applications. Figure 2, on page 7, illustrates the location of the trim-
pots and their approximate calibrated positions. Some applications
may require readjustment of the trimpots in order to tailor the control
for a specific requirement. Readjust trimpots as described below.
Warning! If possible, do not adjust trimpots with the
main power applied. If adjustments are made with the
main power applied, an insulated adjustment tool must be used
and safety glasses must be worn. High voltage exists in this
control. Fire and/or electrocution
can result if caution is not exer-
cised. Safety Warning, on page
5, must be read and understood
before proceeding.
A. Offset (OFFSET) – Sets the
amount of bias in the forward or
reverse direction. The OFFSET
trimpot is factory set for approx-
imately zero offset, which
means that neither the forward
nor reverse direction is favored.
To offset the control in the for-
ward direction, rotate the OFF-
SET trimpot clockwise. To off-
set the control in the reverse
direction, rotate the OFFSET
trimpot counterclockwise. See
Figure 31 and Figure 32.
B. Forward Acceleration (FACC)
and Reverse Acceleration
(RACC) – Sets the amount of
time it takes the control voltage
to reach full output. The FACC
and RACC trimpots are factory
set to 1 second. See Figure 33,
Figure 34 and Figure 35.
The FACC trimpot sets the
amount of time it takes the con-
trol voltage to reach full output in the
forward direction. It also sets the
amount of time it takes the control
voltage, in the reverse direction, to
reach zero output (FACC also sets
the reverse deceleration time). To
increase the forward acceleration
time, rotate the FACC trimpot clock-
wise. To decrease the forward
acceleration time, rotate the FACC
trimpot counterclockwise.
The RACC trimpot sets the amount
of time it takes the control voltage to
reach full output in the reverse
direction. It also sets the amount of
time it takes the control voltage, in
the forward direction, to reach zero
19
!
+10
+5
-10
-5
0
PERCENT OF BASE SPEED
(SHOWN FACTORY SET TO 0%)
FIGURE 31 – OFFSET
TRIMPOT RANGE
C - REVERSE OFFSET
B - ZERO OFFSET
A - FORWARD OFFSET
C B A
C B A
-10
10
ROTATION
SPEED POTENTIOMETER
PERCENT OF MAIN
-100
100
PERCENT OF BASE SPEED
100
-100
FIGURE 32 – OFFSET TRIMPOT ADJUSTMENT
15
10
7.5
0.2
5
1
SECONDS
(SHOWN FACTORY SET TO 1 SECOND)
FIGURE 33 – FACC
TRIMPOT RANGE
1
7.5
10
15
SECONDS
0.2
5
(SHOWN FACTORY SET TO 1 SECOND)
FIGURE 34 – RACC
TRIMPOT RANGE
-100
F
W
D
A
C
C
E
L R
E
V
A
C
C
E
L
F
W
D
A
C
C
E
L R
E
V
A
C
C
E
L
P
E
R
C
E
N
T
O
F
B
A
S
E
S
P
E
E
D
100
TIME
FIGURE 35 – FACC AND RACC
TRIMPOT ADJUSTMENT