Circuit Testers

A crucial part of automotive maintenance, circuit testers allow you to check various electrical connections in your car to ensure optimum performance and functionality of your vehicle. Here at Cromwell, we have a wide range of circuit testers from our quality, trusted own brand Kennedy® and national leading brand Sykes-Pickavant.

What are circuit testers?

Circuit testers are a product that allows you to test for electrical glitches in your automobile, which in turn allows you to replace the correct part to solve the problem. There are various different types of circuit testers, the most common being continuity testers. These consist of a cable, with one end attached to a - normally stainless steel - contact probe which is sharp to allow for testing through wire insulation and the other end possessing an insulated crocodile clip which can be attached to your power source. The continuity tester contains a bulb, which will light up when a circuit has been completed, letting you know whether that element is working as expected. To test your vehicle's battery, you commonly place the crocodile clip to the negative end of your battery, and use the probe to test connections on the positive side of your battery or vice versa to check negative connections. The probe can also be used to test for faulty fuses. Some more modern models of circuit tester will use LED lights as opposed to a bulb, with one LED signifying a ground connection and the other signifying a power connection.

When are circuit testers used?

Circuit testers are commonly used by electricians as well as those wishing to test electrical components in vehicles, whether this be a mechanic, automotive specialist or an enthusiast. As with anything involving electricity, it's crucial that you read all safety instructions carefully and if in doubt, ask a trained professional to help undertake any testing.

Considerations when choosing a circuit tester

• Voltage of system - Most circuit testers have a voltage limit, meaning they can only test circuits up to a specific voltage. This varies depending on the model, so it's always advisable to check the voltage of your system and the limit that your desired circuit tester has before purchasing.

• Power - Not all circuit testers are suited for use with the power on and are only suited for dead tests. Dead testing requires the vehicle's battery to be off and detached - this is always the case with continuity testers, which are a type of circuit tester. It's best to check whether the circuit tester type that you choose is suited for use when the power is on if this is your preference.

Circuit testers jargon buster

We want to make it easy for you to shop our range of circuit testers, so here are some key terms that will help you understand the range and applications a little better.

What do the ground and power connections mean?

Whilst this may seem complicated, the difference between the two is simply the difference between the positive and negative side of the battery.

For example

Negative = This side of the battery is referred to as the ground or chassis
Positive = This side of the battery is commonly referred to as the power or 12V

FAQs

Can I use a continuity tester when the circuit is switched on?

No. Unlike some other circuit testers such as voltage testers, continuity testers may only be used when the circuit or power is switched off, or when testing devices or connections that exist outside of the circuit.