A fundamental rule of electrical theory is that electricity needs a continuous path in order to properly function, and if there is any obstacle in its path then a circuit cannot be formed and electricity will not flow. This is the basis for all electrical circuits and therefore all types of electrical installation, equipment and appliances. A continuity tester helps to determine whether electricity will flow in a circuit and is therefore an essential tool to any electrical tester or engineer.
What does a continuity tester do?
We have established that a circuit needs to be continuous in order for electrical current to flow, so a continuity tester enables us to determine if an electrical circuit can be made between two points, ie. the electrical component is working as it is designed to.
The continuity tester can also measure any resistance in the circuit. Low resistance means that the circuit is closed and has electrical continuity, while a high resistance means the circuit is open and has little or no continuity. The aim is always to have zero resistance for electrical continuity. The continuity tester can be used to determine if a circuit breaker is working properly and it can also be used for fault detection testing, ie. to establish whether two points are connected in a circuit which shouldn’t be.
How does a continuity tester work?
A continuity tester is a small hand-held unit with two connecting leads. In the body of the unit is an internal battery. This sends an electrical current of small voltage through one of the connecting leads/probes and if the other lead/probe receives electricity, this means the path between the two points is unbroken and a circuit has been established, so the tool responds by either lighting up or emitting a bleep. If there is no such indication that means the path in the circuit must be broken.
When we are using the continuity tester on an electrical item we need to ensure the appliance or device is switched off and unplugged, ie. there is no current running through it, otherwise the electrical tester could be injured carrying out the test. So safe isolation is an essential element of the continuity testing programme.
What do we use a continuity tester for?
The continuity tester can be used to test switches, fuses, electrical connections and conductors. It is a quick and simple instrument that is very reliable and requires minimal set-up, hence it is a very common and popular tool amongst electrical testers. It is very popular in basic inspection and testing of electrical installations before they are put into service. This is because the continuity tester has a variety of uses and can:
- Show whether a circuit contains damaged components or broken conductors
- Show whether the quality of soldering has been good enough during installation
- Provide an accurate resistance test to indicate whether current can flow through the circuit
- Show whether electrical wiring has been compromised, damaged or broken between any two points in a circuit.
At Test Instrument Solutions we carry an extensive range of high quality continuity testers. Some of these are basic continuity testers, while others combine more functions and can also be used as voltage testers.
Video Demonstration
Check out a product demonstration video below on the TIS 1835 Insulation & Continuity Tester:
Please note that this section is for information purposes only. Anyone using equipment referred to in this section must be suitably qualified and/or experienced within the respective field. If in doubt before use, please consult a qualified electrician or engineer & thoroughly read all instruction booklets.