Self-Switching Combination Relays

Self-switching split charge combination/ combi (sic) relays (also known as Caravan Relays) are used to automatically control the power supply to the caravan; ensuring the caravan's refrigerator is powered, and the auxiliary caravan battery charged-up, only when the car's engine is running. Consquently there is no possibility of draining the car battery, just peace of mind for the car's driver.

Having pioneered the self-switching combination relay, we have been improving their performance and reliability through continuous development.

When professionally fitted with the appropriate cable, our smart combination relay products can support the high currents often demanded by a caravan's auxiliary circuits whilst keeping the corresponding voltage drop to an absolute minimum. This ensures the caravan's battery will be left fully charged after towing, with the fridge and other electrical facilities having remained well maintained. This obviously assumes the car itself can deliver the required power and that the alternator is not otherwise overloaded.

TSCx0 Series

TSC30: Self-Switching Combination Relay

TSC30 Self-Switching Combination Relay

The TSC30 self-switching combination caravan relay monitors the supply voltage and automatically switches the supply through two relays. The unit is pre-adjusted to compensate for cable voltage drop under heavy currents.

The TSC30 is designed to cope with loads up to 30A. It is advisable to install the unit in a well ventilated area for best performance, but it has a built in thermostat which switches the unit off in the event of excess system temperature.

The features of the TSC30 are:

  • Factory pre-calibrated, but can be field adjusted if required.
  • Large terminal block that can easily accept 6mm² cables.
  • Internal thermostat to protect the product in the event of excessive temperature build-up.
  • Protected, designed to withstand accidental current and voltage reversals, and is fully snubbed against voltage spikes and other electrical hazards.
  • Simple inline design, aiding ease of installation and fitment.
  • Low cost.

Other models withing the TSCx0 series will soon be introduced with differing current ratings.


Smart Baby Combination Relay

The TF1171 is a single relay solution rated at 15A and is suitable for smaller caravans where only a single switched power input is required. It has both switch-on (normally open) and switch-off (normally closed) terminals.

The TF1171 has also been successfully utilised for isolating the power supply for in-car accessories.



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