Curtis 1244 User Manual page 89

APPENDIX A: GLOSSARY
MultiMode™
The MultiMode™ feature of the 1244 controller allows the vehicle to be operated
with four distinct sets of characteristics. The four modes can be programmed
to be suitable for operation under different conditions, such as slow precise
indoor maneuvering in one mode; faster, long distance, outdoor travel in an-
other mode; and application-specific special conditions in the remaining two
modes. For more information about MultiMode™ operation, refer to Section 3.
OEM
(= Original Equipment Manufacturer)
Overtemperature
Because of their efficiency and thermal design, Curtis controllers should barely
get warm in normal operation. Overheating can occur, however, if the controller
is undersized for its application or otherwise overloaded. The 1244 controller
constantly monitors its internal heatsink temperature. Starting at 85°C, the
drive and braking current limits are linearly decreased from full set current
down to zero at 95°C.
Full current limit and performance return automatically after the con-
troller cools down. Although occasional overtemperature operation is usually
not damaging to the controller, it does suggest a mismatch. If thermal cutback
occurs often in normal vehicle operation, the controller is probably undersized
for the application and a higher current model should be used. Continuous
operation in overtemperature will overstress the power components and reduce
the lifetime and reliability of the controller.
Overvoltage cutoff
The overvoltage protection feature inhibits the PWM and shuts down the
controller, if the voltage exceeds the factory-set limit. Overvoltage can result
during battery charging or from an improperly wired controller. Controller
operation resumes when the voltage is brought within the acceptable range. The
cutoff voltage and re-enable voltage are percentages of the battery voltage, and
are defined by the Battery Voltage parameter setting—see Section 3, page 46.
Plug braking
The 1244 controller uses plug braking as well as regen braking to apply braking
torque to the vehicle's motor. Plug braking takes place when braking is requested
and the vehicle speed is less than the programmed regen speed. During plug
braking, the current is limited to the drive current limit.
A-7
Curtis 1244 Manual,
Rev. E