Measurement of insulation resistance is most often carried out during reconstruction, installation of electrical networks, and also in those terms, which the company is required to check. These are necessary actions to prevent wear on the wiring., which can lead to a short circuit and damage to electrical appliances and be harmful to health.
A device for measuring resistance is called a megohmmeter.. Megaohmmeters are usually classified by possible resistance limits: from 500 to 5000 Volt.
Before measuring, it is necessary to carefully inspect the wiring. (junctions of wires in specialized boxes). Worth noticing, that special access is required to perform such work, and that is why resistance is most often measured by a specialized electrical laboratory, equipped with special equipment and highly skilled workers.
Resistance measurements can reveal the condition of the wiring. Uninterrupted operation of electricity depends on timely measurements, excluding current losses.
Wiring wear depends on:
- high power load, wrong mode of operation.
- voltage values of electrical receivers;
- damage;
- environment (high humidity, high temperatures);
Current leakage may occur, if the insulation value drops to “0.5 MΩ”, which can subsequently cause a short circuit and cause a fire. In order to avoid this, it is necessary to periodically carry out insulation resistance measurements.
It is necessary to contact specialists in time to check the insulation resistance. During all inspection work, the entire load on the electrical network must be disconnected..
How often should measurements be taken:
- Indoors, in which explosive materials are stored must be measured once a year. In other premises – once every three years.
- Lift cables must be checked once a year.
- electric stoves, installed in living quarters, must be checked once a year, in that case, if they are constantly heated.
The test result is provided to the inspector, who must annually conduct a fire safety inspection. All organizations should establish the necessary frequency for insulation testing.. Most often, measurements are carried out during operational tests..
