For inductive and regenerative DC loads, such as a motor, contacts are
often wired in series to provide greater arcing distance. In order to stop
a DC motor quickly and safely, it may be useful to apply a heavy load, or
even a short circuit, to the motor, which will also eliminate possible
high voltage arcing. A snubber or capacitor can be used to reduce the
voltage kick during the time between the opening of the supply contactor
and the closing of the braking contactor.
OR:
The KBBC-24M is a microprocessor controlled, DC-DC battery powered variable
speed motor control designed for 12 and 24vdc Permanent Magnet and Series
Wound DC motors. It has a continuous rating of 40 amps and is capable of
peak currents of 80 amps for 7 seconds. The KBBC-24M low voltage DC Drive
contains many standard features such as current limit, short circuit
protection, speed potentiometer fault detector, over-temperature sensing,
and under-voltage/over-voltage protection. Eight trimpots are provided to
tailor the low voltage DC-DC Drive to exact specifications. Reversing
contactors provide arcless forward, stop and reverse operation. A DC power
contactor allows a low power switch to turn the control on and off. See data
sheet D-905 for complete details.
The KBBC-44M is a microprocessor controlled DC-DC battery powered variable
speed motor control designed for 12, 24, 36 and 48vdc Permanent Magnet and
Series Wound DC motors. It has a continuous rating of 40 amps and is capable
of peak currents of 80 amps for 7 seconds. The KBBC-24M low voltage DC-DC
Drive contains many standard features such as current limit, short circuit
protection, speed potentiometer fault detector, over-temperature sensing,
and under-voltage/over-voltage protection. Eight trimpots are provided to
tailor the low voltage DC Drive to exact specifications. Reversing
contactors provide arcless forward, stop and reverse operation. A DC power
contactor allows a low power switch to turn the control on and off. See data
sheet D-905 for complete details.
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