Some basics about testers before we get into the detail. Generally speaking, there are 2 types, multi-functional testers and single dedicated testers. Multi-functional testers are instruments that combine the functions of several testers, such as voltage tester, continuity tester, and current tester. Dedicated testers have a single function, such as insulation tester, ground detector or circuit breaker tester.
Furthermore, electricians will test 2 types of circuits, AC or DC. AC stands for alternating current, which is the type of electricity that standard outlets use in homes and offices to power computers, televisions, clocks, etc. The other type is DC, or direct current, which is the type of electricity that’s used by cars in many countries.