On Thursday 06 December 2007 08:19, keith smith wrote: > A basic surge protector uses a capacitor. Once the capacitor is at > capacity it becomes a basic extension cord. WRONG!
lets explain a little here.. firstly, the "surge protection devices" are not capacitors. they are MOV's (Metal Oxide Varistors) with a very fast clamp time and high current rating. However, they have a "shelf life" after which (usually about 10,000 transients) they cease being functional (hence being nothing more than a regular multiplug extension). Now, according to the IEEE, a scenario of "defense in depth" is often best. we start right out at the mains breaker panel with a household MOV (10,000 AMP capable) and some large line filters (400 V AC each leg, low pass cutoff @ 100 hz outer casing connected to a ground strap run to a ground spike right below the breaker box). on each outless in the house, a smaller version of that mains filter along with some smaller MOV's (4 should do). additionally, any electronic equipment that you consider worth it (computer etc) should use a UPS/power conditioner (of course, at this point, the lines are pretty filtered, but, it never hurts). lastly (and I do this with all my computer gear), install a block of MOV's, fuses and zener diodes at the output power blocks of your computers PSU (5.5 V zeners for the 5 volt lines, 3.5 for the 3.3 V lines, etc) this way. if your PSU should have a catastrophic failure, at least your motherboard (and all components therein) sre reasonably safe. granted, this may cost some $$$, but after a while, it does pay for itself in reduced cost of repairs, losses, etc. btw, on those circuits that run motors (such as your AC, refrigerator, washer/dryer, etc, place extra heavy duty MOV's and extra line filtering. this will reduce the transients caused by such devices from entering the rest of the house wiring. --------------------------------------------------- PLUG-discuss mailing list - [email protected] To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss
