The HPA-Limiter-1 is designed to limit the excessive inrush current to a safe level, found at turn on in toroidal transformers of 300VA+ rating. This excessive current surge is mainly caused by the toroidal core magnetising currents been unstable for the first 250ms or so after power is applied to the primary winding/core. This can in most cases trip the household circuit breakers, which is most irritating and inconvenient. The Limiter has the added bonus of limiting the charging currents passing through the bridge rectifiers as well as the large main filter capacitors found in most conventional linear power supplies. Which in turn help to remove the stress from these vital components.

The HPA-Limiter-1 has been tested to work on toroidal power transformers as large as 4KVA and load tested to 2400 watts, making it more than tough enough to handle most installations with ease. The HPA-Limiter-1 could also be used to protect most switchmode power supplies.

The HPA-Limiter-1 is designed to work in 100 volts AC to 270 volts AC at 50-60 hz allowing it to be used in most world wide AC mains installations.

OEM or DIY Enquiries are welcome!

• Constructed on a heavy duty 3 Ounce copper FR4 PCB.
• 30 Amp - 380 volt contact rated relay.
• Heavy duty surge limiting NTC thermistors.
• Quick and easy installation with FASTON connections.
• Fast reset and enable with rapid mains power cycling.
• On board 24 volt voltage regulator.
• 1 sec approximate surge limit delay