Voltage Sensitive Relays

Smart Power Management for Dual Battery Setups

Need a way to run extra gear without draining your starter battery? A voltage sensing relay helps you power your gear while keeping your engine battery protected.

It links your second battery when you’re driving and splits it when you stop. This means you can run camping fridge, lights, and more without worry. The system does all the work for you. No switches needed.

What is a Voltage Sensitive Relay and what does it do?

A voltage sensitive relay (VSR) is an automatic switch that opens or closes based on system voltage. It turns on when voltage rises above a set level and turns off when it drops below that level. This switching function helps manage power flow without needing manual input.

VSRs are often used to link or isolate batteries, like in dual battery systems, but they’re also used in car audio and other setups where voltage-based control is needed. They protect circuits and help distribute power safely across your 12V or 24V system.

When do I need a VSR?

A VSR is used when you want to control power based on voltage. It automatically switches a circuit on or off depending on how much voltage is present. You’ll find VSRs in setups where you need to connect or isolate batteries, control accessories, or manage power between different parts of a 12V or 24V system.

They’re often used in dual battery setups to protect the starter battery. They’re also found in car audio, marine, and off-grid power systems where voltage needs to trigger a relay without manual input.

Does it work with 12V and 24V?

Yes, many VSRs work with both 12V and 24V systems.

They’re built to handle a wide range of setups. That includes standard cars, heavy-duty trucks, and off-road rigs. The VSR checks the system voltage and switches accordingly, without needing extra parts.

Why Buy Voltage Sensitive Relays from Outback Equipment?

• Australian Owned & Operated – Based in Brisbane, we’re ready when you are. Shop online with confidence or drop by at 1 Murdoch Circuit, Acacia Ridge QLD 4110. Need help choosing a tester? Call our local team on 1300 854 185 for advice on battery setups for 4WD, caravan, or marine use.
• VSRs for Every Setup – We stock VSRs suited to 12V and 24V systems. Perfect for dual battery setups in 4WDs, caravans, and boats. Choose from simple plug-and-play units or heavy-duty models for bigger builds.
• Plenty of Payment Options – Pay your way with Afterpay, Zip, PayPal, Visa, MasterCard, or direct deposit. Get the tools you need now and sort the rest later.
• Australia-Wide Delivery – No need to chase it down in-store. We deliver battery testers right to your door, ready for your next install, upgrade, or weekend trip prep.