Precharge resistor


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Precharge resistor

Most controllers have banks of capacitors inside that help to smooth current flow. The capacitors gradually discharge when the controller is shut off, and recharge when it's switched back on.

To protect them from potentially life-shortening high amperage current in-rush when the controller is switched on, a precharge resistor is used to slow the flow of juice to a more capacitor-friendly rate.

In the ForkenSwift, the resistor we're using is one of the forklift's spotlight bulbs.

View all ForkenSwift galleries > DC motor controller ...

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Finned aluminum heat sink
(Inset: controller mounted on the heatsink)

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Precharge resistor
Most controllers have banks of capacitors inside that help to smooth current flow. The capacitors gradually discharge w...
Curtis 1204-412: adjustable features
Note the adjustable current limiting (CL) and acceleration rate (ACC). Plug braking (PLUG) mode isn't used.

For maxi...