Service manual

Electrical Service Manual V4.0
3
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CURTIS 1213 CONTROLLER
CONNECTIONS
BATTERY
The connections from the controller to the battery are made using ring terminals that are
fastened to the lug style terminals on the controller. It is important to tighten theses termi-
nals with two wrenches using one to hold the nut and one to turn the bolt so undo stress is
not put on the terminals. The
POWER SWITCH
The power switch is a very simple circuit. +24 volts is taken from the main circuit breaker
and it is switched on and off to the controller thru a SPST lighted switch. The signal is sent
into the controller thru a 16 gauge red wire into pin #6 of the P1 connector.
THROTTLE
The throttle uses a 5K hermetically sealed potentiometer to sum the high and low reference
from the controller. The output from the potentiometer is a varied voltage from +0.2 volts
+/- 0.1 volt to 4.8 volts +/- 0.1 volt. This signal is then sent to the controller on pin #16 of
the 16 pin Molex connector.
REVERSE SWITCH
The reverse switch sends +24 Volts DC from the positive buss bar to Pin #11 on the 16 pin
Molex connector on the Curtis controller. This tells the controller that when it receives a
throttle signal from the throttle potentiometer to move in a reverse direction.
BRAKE OUTPUT
The parking brake output from the controller is used to activate the “#2 Relay” in the Central
Command I. The coil on the “#2 relay is driven by pins 1 and 3 on the 16 pin Molex con-
nector. This contactor is wired with a suppression diode across it to prevent the controller
from damage when the coil is turned off. The silver stripe on this diode goes on the posi-
tive side of the coil connection.