Because of the risks it poses, many standards stipulate leak current test methods, the performance of test equipment, limits for leak current, and other factors related to leak current. The bench-type 3156 Leak Current HiTester by itself, without any additional equipment, is capable of performing tests that comply with standards for a wide range of equipment, from general purpose electrical equipment to medical electrical equipment. The 3156 also is equipped with functions and an interface that support embedded test lines.

In order to avoid dangers such as electric shock, electrical equipment is designed so that those portions that are likely to be touched by people are insulated from the power source. However, the insulation resistance is not infinite, so there is always some leak current present. Furthermore, the extent of the leak current changes over time as the insulation deteriorates. To determine their safety level, the 3156 Leak Current HiTester can prove to be highly valuable, both as a tester on the production line as well as a maintenance and inspection tool.

The power supply voltage for the 3156 does not need to be changed, even if the supply voltage for the equipment being tested is different. The difference can be managed by controlling the line supply voltage for the equipment being tested. This helps prevent malfunctions due to the wrong voltage being input for the 3156 power supply.