Service manual

Electrical Service Manual V4.0
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CENTRAL COMMAND I
HOW CENTRAL COMMAND I SYSTEMS WORK
The Curtis system is a solid state speed controller that replaces the old style resistor-based
speed control systems. The solid state system eliminates runaway machines and burnt
electrical components while conserving energy and making the machine operate more
smoothly.
The Curtis system has the ability to check wires before sending the full amount of power
through them assuring safe and proper operation of the machine.
The Curtis system can electrically test relays to make sure they are sound before energiz-
ing them and powering the traction system.
SELF TEST EXAMPLE: MODEL 40/3700 – When you turn on the key, the key switch sends
power to pin #15 of the central command, turning on the Curtis controller. The controller at
this point electrically checks it self internally as well as all the wiring and devices attached
to it. It can not power a drive motor until these checks are performed.
When you step on the foot pedal, the Curtis turns on Relay #1 (the MAIN relay), providing
the Curtis with the power it needs to run the traction motor. At the same time this is occur-
ring the Curtis turns on the “#2” relay which turns on the vac motor, the scrub motor, the
Deltrol solution valve, the brake release, the headlight, etcetera. This second relay must
operate properly for the traction motor to energize.
When you release the foot pedal or the throttle button the Curtis controller diverts the power
generated from the drive motor, which on deceleration acts like a generator, back into the
batteries to recharge them a small amount.
1228
Used on models:
Factory Cat: 2000 series
Tomcat: 2000 Series, 200 Burnishers
Definitive characteristics:
Blue in color
Small package
DIAGNOSTICS
See Chapter 5