Short Circuit Protection (Multifunction Decoder)
Summary: Short Circuit Protection refers to mechanical or electronic means of protecting a device from damage should a Short Circuit occur.
Short Circuit Protection
In a multifunction decoder a mechanical method is not practical. No one wants to disassemble a locomotive to reset a circuit breaker or change a fuse. That leaves electronic methods. The decoder can use two techniques: thermal and current limiting.
Thermal protection means that if a short occurs, the current flow would cause an increase in heat, and when a component gets too hot it can fail. Some ICs are designed with a thermal shutdown system that attempts to protect them from overheating from overloading or a short.
Current limiting is done by monitoring the current flow and preventing it from exceeding a preset limit.
This does not mean that pico fuses are also on the PCB. Blowing those would require a trip to the manufacturer for repair.
The primary defence against short circuit damage would lay with the booster, or a power management device. The second line is good wiring, as a voltage drop drop will increase the current flowing through the circuit. Remember, wiring is important as many boosters rely not on the amount of current, but the rate of change.
- Short Circuit Protection in the booster is there to protect the booster!
The secondary defence is check your wiring, and do the initial testing on a programming track which limits the current. Addition of a device such as the PTB-100 by Soundtraxx can also help by identifying a problem.