Method of changing current by toggle switch
Release time：2018-09-25 Clicks： Click
How to change the current of the toggle switch is described in detail.
The advantages of this measuring method are quite intuitive and convenient. The disadvantage is that the current passing through the switch is very small and the oxide film on the contact surface can not be destroyed, which results in a large error (on the high side). Therefore, this method is not recommended in the circuit resistance measurement of high voltage switches. Indirect measurement by voltage drop method (volt-ampere method): the voltage drop method is the value of the DC current on the switch socket, with the millivolt meter to measure the voltage drop (mV) between the inlet and outlet lines of the switch socket, and then calculate the main circuit resistance of the switch socket by Ohm's law. A measuring circuit with a transformer and a silicon rectifier. At the same time, the voltage drop method is recommended to measure the main circuit resistance of the switch socket because the current passing through the test sample is large enough to destroy the metal oxide film on the contact surface, reduce the measurement error and the measured value is more accurate. The complicated calculation of the switching switch shows that if the attenuation time constant on the switching socket circuit is set at 45 ms, and the DC component in phase A and B is connected at the same time, when the DC component in phase A and B is up to o.866, the maximum DC component in phase B (assuming it happens to be a side phase) can reach 112%. If the attenuation time constant in the switching socket system is increased to 60 ms, the maximum DC component in the six-phase (three-phase) system will reach l15%. In the split test, the DC component at the moment of contact separation is related to the duration of short circuit, that is, the time of breaker opening and relay protection action.