FAQ:Power Cab Overcurrent Protection

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The Power Cab has an overcurrent sensing circuit for basic self-protection which will continuously attempt to reset itself until destroyed. Neither the Power Cab or the P114 power supply have circuit breakers or fuses. Using a DCC circuit breaker such as NCE's EB1v1.1 is strongly recommended to protect your Power Cab from damage.

NCE did include a software fix (1.28b) which would disconnect power to the track if an overcurrent event was detected in the booster output. It would disconnect and reconnect the track power until the short was cleared or the Power Cab itself was damaged. If the short was not corrected and promptly cleared, the Power Cab would overheat, resulting in damage to itself. Do not leave a Power Cab unattended while operating a train.

  • The current limitation of the Power Cab is imposed by amount of heat the case can withstand. As the current increases the amount of heat dissipated by the booster increases; being enclosed within the handheld throttle's plastic enclosure limits the ability to effectively dissipate excess heat. The designer enforced this limit, specifying a low current power supply.

NCE recommends a circuit breaker on the output of the Power Cab. Their EB1V1.1 was designed with the Power Cab in mind.

Other manufacturer's devices can be used, but ensure they can operate at the lower current levels of the Power Cab.

  • Power Input Requirements: 10-15V regulated DC 3A maximum
  • The preferred method for adding more capacity to the Power Cab is with the SB5 Smartbooster

From NCE's Zendesk:

  1. The NCE Power Cab does not regulate the track voltage. The power supply does.
    1. The DCC track voltage is similar to the power supply's DC output voltage rating. Get a power supply between 12 and 14VDC.
    2. 13.8VDC is a common voltage which emulates a car battery's voltage.
  2. The NCE Power Cab does not limit the current. The power supply does.
    1. The Power Cab's current rating is determined by the power supply's maximum current.
    2. If the current exceeds three amps, the Power Cab shuts down to protect itself.
    3. Use care regarding the selection of a power supply used with the Power Cab.
  3. One cannot run three amps of current continuously with the Power Cab. It will overheat causing deformation of the Power Cab shell due to excessive heat build up.
    1. It is strongly recommended to use multiple DCC circuit breakers with a 2 amp trip current. The Power Cab feeds all of these circuit breakers, which feed various parts of the layout. The DCC circuit breakers isolate any short circuits, protecting the PowerCab from overheating during a short circuit event.
  4. The Power Cab's long flat cable loses a lot of voltage and may get warm when running a lot of trains. The cable and associated telco RJ jacks and plugs are not designed to handle 3 Amps efficiently.
    1. Replacement Power Cab cables must be sourced from NCE. Other cables may not be adequate for the purpose.