Curtis PMC 1209B/1221B/1221C/1231C Manual
15
WIRING
Figure 10 is a schematic diagram of the 1231C installation shown in Figure 8.
This wiring scheme isolates the control wiring in the driver
’
s compartment from
the high voltage connections of the power drive system, thus providing maximum
protection for the driver.
Fig. 10
Basic wiring configuration, Curtis PMC 1231C controller.
B-
B+
A2
M-
+
–
M
A
IN
S2
A2
S1
A1
POTBOX
MAIN
KEYSWITCH
THROTTLE
MICROSWITCH
CONTROL
WIRING
FUSE
PRECHARGE
RESISTOR
CIRCUIT
BREAKER
T
R
A
CT
IO
N
B
A
T
T
E
R
Y
KSI RELAY
12V
A
UX
ILI
A
R
Y
B
A
T
T
E
R
Y
K
S
I
RE
L
A
Y
+
–
KSI Wiring
The keyswitch input (KSI) circuit includes inputs from the keyswitch and from
the various interlocks. The controller KSI is used to turn the controller on and off.
KSI is turned on by connecting it to battery B+. Any positive voltage greater than
about 8 volts will turn on the controller, but usually the full vehicle battery voltage
is used.
In its simplest form, KSI is operated by a keyswitch that turns the vehicle off
and prevents unauthorized use. The keyswitch should also turn off the main
contactor and
—
in 1209B, 1221B, and 1221C applications
—
the forward/re-
verse contactors. This will act as a safety feature by removing power from the
motor control system when the keyswitch is off.
Interlocks (seat switches, battery charger interlocks, etc.) should be wired in
series so that they turn off the controller KSI and the contactor(s).
A keyswitch relay is recommended for high voltage systems. It should be
wired as shown in Figure 10. This relay prevents the full battery pack voltage