Indoor Disconnect Switch

Indoor Disconnect Switch

An indoor disconnect switch is the most commonly used high voltage switching apparatus. It is used to break the circuit with no load current to separate the equipment that needs to repair and the power so as to ensure the safety of the maintenance personnel. The indoor disconnect switch doesn't have special arc-extinguishing equipment, so it can't break load current or short-circuit current. Therefore, indoor disconnect switches can be operated only after the circuit breaker breaks the circuit.

Common Problems and Solutions of Indoor Disconnect Switch
1. When the indoor disconnect switch is in operation, what is the reason that causes the overheating of the contact part?
It is caused by overload, increased contact resistance, and that the switch is not completely closed in operation.
2. What are the reasons that make the contact resistance of the indoor disconnect switch increase?
The first reason is that the repulsion force at the contact point between the switch blade and the base, so the knife isn't closed tightly and causes surface oxidation to increase the contact resistance. The second reason is that when the disconnect switch is pulled or closed, arc is produced and the contact terminal is burned, and the contact resistance is increased.
3. How to judge the contact terminal of the disconnect switch is overheated or not?
You can judge by the paint's color of the disconnect switch's contact part or the changes in the color of the temperature testing plate, or the color of the blade. At present, it is decided by the result of infrared thermometry.
4. How to deal with the overheating of the contact terminal and contact point of the disconnect switch?
First of all, report to the dispatcher, try to reduce or transfer load, and strengthen monitoring. Then begin to deal with the problem according to different connection lines.
a. Double bus connection. If the switch blade of one busbar is overheated, stop operating the overheated disconnect switch by changeover busbar and stop repairing.
b. Single bus connection. The load should be reduced. Strengthen supervision and try to decrease the temperature. If conditions permit, stop using the disconnect switch.
c. If there is by-pass circuit breaker, replace the disconnect switch with the by-pass circuit breaker.
d. If the line side disconnect switch is overheated, the solution is similar to single bus connection. Stop repairing as soon as possible. At the time of maintaining operation, reduce the load and strengthen supervision
e. One-and-a-half breaker arrangement. It can operate in open loop.
f. The contact terminal and contact point of the busbar side disconnect switch are overheated. After pulling the disconnect switch, through on-site inspection, if the conditions permit live line work, live line untie the terminal of the busbar side down conductor. Then deal with the problem.
5. When the electric operation of the indoor disconnect switch doesn't work, how to find out the reason?
First, check whether there is something wrong in the operation. Then check whether the operating power source circuit and the driving power circuit are normal or not, the fuse blows out or becomes loose or not, and the electric closed circuit is normal or not.

As a professional indoor disconnect switch manufacturer in China, we have accumulated many years of production experience of power transmission equipment and power distribution equipment. In addition to disconnect switches, we also provide wind turbine generators, circuit breakers and load break switches at a competitive price. Our products have been awarded the certificates of KEMA, GOST, CCC, TUV, WTGS and CB. They are successfully exported to more than 30 countries and regions, such as America, Germany, Russia, Iran, South Africa and Argentina. We welcome global customers to contact us!