natfuelbill
Senior Member
Is 4160 less prone to escalting problems that can reduce maintenance. Flashover etc.
Is 4160 less prone to escalting problems that can reduce maintenance. Flashover etc.
Can you re word that? Less prone compared to what? How do escalating problems reduce maintnence? I don;t understand the question(s).
What challange? First you agreed with me, then you posted some part of a study that had little to do with the subject of tracking in enclosed equipment. Sure porcelin might be better in a wet environment, and hard to argue that dirt may not stick to it as easily either, but they also are fragile and when you throw a HVL switch there is a pretty serious shockwave that could shatter a porcelin insulator. Which is why, just maybe, that Square D used the material they did for that application (They do know what they are doing sometimes).
But my point is, and has been throughout this entire thread, that maintaining the heaters working and cleaning the switches every couple of years is a lot more important than the materials used.
I've played around with older bottle style ignition coil. Hooked it up something like this:
http://wiki.4hv.org/index.php/Ignition_coil
Well, I got the voltage to get high enough to arc over from center, over the edge to one of the terminals. The material is phenolic resin, however the arcing burned the surface and created a carbon track and insulation was done.
If you have an arc over over anything that can char, it will leave a carbon track and draw a conductive path. Since porcelain is inorganic, it is immune from carbon tracking.
Indeed there was no evidence of arc-over.
You usually won't see tracking in LV equipment, tracking and corona occur somewhere between 2kV and 4kV, depending on the environment.
I hate it when that happens. :grin:...which corroborates what weressl have observed
It can supposedly happen even at 120v in very humid climate. Accumulated dust at the outlet can get wet from dew or condensate on the wall dripping on it and resistance becomes low enough to make it a heating element.
http://www.jniosh.go.jp/icpro/jicosh-old/english/topics/Tracking.html
This is something that was done in a lab to duplicate the condition in connection with a fire investigation which corroborates what weressl have observed
I have never witnessed PD activity in LV applications.