Safe Operation of Hipot Tester
The principle of hipot tester is to apply a voltage higher than normal working voltage to the insulator of the device under test for a specified period of time. If the insulation is good enough, the voltage applied to it will only produce a small leakage current. If a device maintains its leakage current within the specified range for a specified period of time, it can be determined that the device under test can operate safely under normal operating conditions. This article will introduce safe operation of hipot tester.
- Grounding. Improper grounding or ungrounding may lead to electric shock accidents. To ensure safety, the instrument must be reliably grounded. There are two methods to ensure the reliable grounding of the instrument: connect the power cord to a three-phase grounded power socket; if the three-phase power socket is not grounded, there is a protective grounding terminal on the rear panel of the instrument, and connect the protective grounding terminal to the ground.
- Continuous and fast switching power supply is strictly prohibited. After turning off the power switch on the front panel, if you want to turn the power switch on again, be sure to wait a few seconds or more after turning off the power switch. Do not turn the power switch on repeatedly and frequently. If doing so, the protection device of the instrument may not be able to perform the protection function properly; when the tester is testing the output high voltage, please do not turn off the power switch, unless it is an emergency.
- It is strictly forbidden to short-circuit the high-voltage output to ground. Do not short-circuit the high-voltage test lead of the tester with a nearby AC power line connected to ground or other nearby electrical equipment. If there is a short circuit, the case of the tester may be filled with high voltage, which will be very dangerous. Make sure that the protective earth terminal of the instrument is connected to the safety ground. If the ground terminal of the instrument and the safety ground are connected together, even if the high voltage output terminal and the current return terminal are short-circuited, the instrument will not be dangerous and the shell will not have high voltage.
- Do not use external voltage. Do not apply high voltage generated by external devices to the high voltage output port of the tester. Because the voltmeter inside the instrument cannot be used as an independent voltmeter, the external voltage may damage the voltmeter.
Personnel Standardized Operation Requirements
- Personnel Qualification: The operation must be performed by skilled personnel, who understand the basic concepts of voltage, current and resistance; the operator must know that during high-voltage testing, voltage flows from the high-voltage output port of the tester, passes through the tested body, and returns from the current terminal into the tester; during this process, touching anything with high voltage will cause an electric shock.
- Safety Rules: Operators must be given special training, understand the test procedures and safety regulations and read the instructions carefully.
- Dress Code: Operators are not allowed to wear clothes with metal decorations or accessories such as watches. The hipot tester must not be operated by persons with heart disease or with a pacemaker.