If you have low or medium voltage switchgear that you are responsible for taking care of, you need to know what to look for when you inspect your switchgear. You should inspect your switchgear on a monthly basis to ensure that the system maintains its reliability. You may need to inspect your equipment more frequently if your experience any scheduled or emergency shutdowns, if your switchboard experiences an overload or if there are extreme weather conditions in your area.
The first thing you need to keep an eye out for are cracked insulating supports or broken insulated supports. If your insulating supports become damaged, the supporting components of your switchgear system will be subjected to additional mechanical stress, which can cause your entire system to fail.
Physical damage can happen because of a variety of different circumstances. It can happen because of the switchgear being mishandled during the shipping or installation process, or even because of heavy-handed maintenance. It can also be caused by strain from other insulating members that are not properly mounted or by thermal cycling.
Second, keep an eye out for heat damage. Heat that is just a little over the designed levels can damage the insulation on your switchgear.
When heat damages your switchgear, it will look discolored. Your switchgear will look darkened on the outside and varnished coatings may look cracked or be flaky. The tape and cable may feel brittle. The taped conductors or laminated insulation may have lost their laminated cover. You may see melting and oozing of different substances from within the assembly.
If you see heat damage, you need to figure out where the excess heat is coming from and fix all the damaged components on the switchgear.
You don't want moisture to get into your switchgear equipment. Moisture generally gets into your switchgear due to high amounts of humidity in the air. You are probably not going to see moisture on the switchgear when you inspect it, which is why you need to know what signs to look for that moisture was present.
You may see a dust pattern on the equipment like you see on your vehicle when it is dusty and it rains lightly. You may see rust around the metal housing. You may see craters on a bus. You may see what look like dirty water puddles. Finally, you may actually see condensation on the metallic surfaces of the equipment.
If moisture is an issue, replace the damaged parts and install a humidifier in the area to better control the humidity levels in the area.
Make sure you know how to look for when you inspect your low to medium switchgear equipment for damage. If you need assistance inspecting your switchgear, call in the professionals.