Specifications

Curtis PMC 1223/33, 1225/35, 1227/37 Manual

A-7

APPENDIX A: GLOSSARY

LEDs

The 1223/33, 1225/35, and 1227/37 controllers allow for the use of Light

Emitting Diodes (LEDs) to show the condition of certain switches and to provide

system fault information—see Section 2, page 25.

Load compensation

(see IR compensation)

Missing brake detection

If the electromagnetic brake coil circuit is open, the controller inhibits driving and

shorts the motor. If a mechanical brake release lever is used, it is recommended that

a switch operated by this lever be wired in series with the brake coil to inhibit

driving when the brake is mechanically released, as shown in the wiring diagrams.

This provides a safety feature by ensuring the vehicle cannot be driven when the

brake cannot be engaged. A brake coil disable switch or a self-resetting brake is

required by TÜV regulations.

Momentary switch input

A control input conﬁgured for a momentary switch changes its state each time it

receives a B+ signal. If the B+ signal is removed, the control function remains

latched. For example, if the Mode input is conﬁgured for a momentary switch and

the controller is in Mode 1, activating the switch momentarily (applying B+) puts

the controller into Mode 2. The controller will remain in Mode 2 until another

B+ signal is received. When the switch is again momentarily activated (B+ again

applied to the Mode input) the controller will transition back to Mode 1

operation. Membrane switches built into a control pad are usually used with

momentary control inputs.

MOSFET

A MOSFET (metal oxide semiconductor field effect transistor) is a type of

transistor characterized by its fast switching speeds and very low losses.

Motor voltage fault

The motor voltage fault check circuit veriﬁes that the average voltage being applied

to the motor corresponds to that commanded by the throttle input. If there is a

discrepancy between the throttle request and voltage across the motor, the

controller is shut down. The motor voltage fault check is mandated by TÜV

requirements.