Recent content by mnnc

Hi I just recently found out that we can use utp cables for our cable tv system, we'll just have to buy the proper termination kit, balun to filter. - Is utp cables less prone to interference than shielded coaxial cables? - how does the Balun works?

unclebob, what software do you recommend in obtaining the value of the VCB rating. the VCB rating will be located at the primary size of the transformer.

waross LionelHutz dbaird, Thanks guys for the info. i'l look it up.

Hello warossare you referring chapter 9 in the NEC? We don't use nec here. we use pec, but almost all of its contents are gathered fro nec. we might have a mix up on the chapters. what article should i look for. Thanks

Guys I have a question regarding in choosing the correct breaker rating of a motor. Given a 20hp pump motor with 230V, 3Phase, 60Hz. what should the the ampere rating of the correct breakers to be used? Is this correct 20Hp, 3ph, 230v in table is equivalent to 54amps. therefore we multiply full...

Hi guys, I would like to refresh myself on how to compute for the vcb rating, if you have am 2MVA transformer rated 34.5kv(pri)/ 380V/220V(sec). Is this formula correct? I= kva(1000)/ 1.732(34500). I came up with the 33.47amps. I have been given a munufacturer's spec with a vcb rating of 630A...

dpc, thanks for the insight. we'll do check on the ballast manufacturer.

Hi advidana, there are no square d company here. Those the are, are distributers of square d. Where can i get copy of motor controls fundamentals? Thanks.

Thanks waross for the fascinating post. Everyone here learned something.

hi waross Can you explain the various scenarios with calculations for the various failure modes of a Star Delta connection.Star Thanks.

dpc, A friend of mine also an Electrical Engineer told me that he has encountered a problem, the fluorescent tubes in an electronic ballast are prone to busted than ordinary ballast.

The transformer might be equipment grounded. You can ground the transformer by placing ground rods connected to a bare copper wire with ground clamp, and connect it to the body of the transformer. I hope this helps.

I'm wondering why our 1200Amps, 460v, 3ph impact type circuit breakers always trips from the main switchgear when there is a ground fault on its load side. The thing here is that the main breaker from where the sorce ground fault originated did not trip instantly eventhough its the nearest...

Hi, I would appreciate it if anyone who can explain what are the advantages and disadvantages of transformer connected delta on the secondary side? connected Wye on the secondary side?

What are the effects of having a capacitor bank on electronic ballast fluorescenbt fixtures?