Insulation monitoring device
Encyclopedia
An insulation monitoring device monitors the ungrounded system between an active phase conductor and earth
. It is intended to give an alert(light and sound) or disconnect the power supply when the impedance
between the two conductors drops below a set value, usually 50 kΩ
.The main advantage of the device that it allows uninterrupted power supply to important consumers such as medical, military and etc. Even if there is a failure(i.e phase touches ground) there are still no danger to the personnel.
It works by injecting low level ac or dc on the line and detecting.
Ground (electricity)
In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....
. It is intended to give an alert(light and sound) or disconnect the power supply when the impedance
Electrical impedance
Electrical impedance, or simply impedance, is the measure of the opposition that an electrical circuit presents to the passage of a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current circuit...
between the two conductors drops below a set value, usually 50 kΩ
Ohm
The ohm is the SI unit of electrical resistance, named after German physicist Georg Simon Ohm.- Definition :The ohm is defined as a resistance between two points of a conductor when a constant potential difference of 1 volt, applied to these points, produces in the conductor a current of 1 ampere,...
.The main advantage of the device that it allows uninterrupted power supply to important consumers such as medical, military and etc. Even if there is a failure(i.e phase touches ground) there are still no danger to the personnel.
It works by injecting low level ac or dc on the line and detecting.