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Transformer supply question

Transformer supply question

Transformer supply question

(OP)

I just had a new transformer installed at 15KVA transformer to add to the existing 25KVA transformer as building was becoming overloaded.

I left the local power company a bunch of cables to play with, but insisted they upgraded the existing line from the 25KVA transformer to cable that can handle 160AMPS at 220V.

I also made them increase the electric meter capacity from 100AMPS to 200AMPS as it was burning under the existing load.

However the terminal box the new electric meter slides into was rated at 100AMPS, so the terminal connections couldn't accept the wire size I had given them which was rated to 160AMPS at 220V.

So they used the 160AMP at 220V cable only on the live wire connection from 25KVA transformer to the electric meter. They then used some much smaller cable with max rating 80 AMPS at 200 Volts to connect the neutral wire from the transformer to the electric meter.

Is this going to cause me problems? They say its ok because its the neutral wire. But I can't believe this.

The 25KVA often is utilized to maximum load which is 100 AMPS so above the cable sizing.

If it won't melt will it increase my electric bill?


RE: Transformer supply question

It's hard to say as I'm not clear on Philippines electrical distribution. Obviously the best bet is at least the same size neutral as the supplies but a smaller neutral could work if most the loads are actually 220V in which case no power or current is added to the neutral. This train of logic only works if you have 110V service Hot-to-Neutral and 220V service Hot-to-Hot.

All of this is a moot point if there is an Authority Having Jurisdiction, inspectors, and local rules to follow.

Or are you talking some sort of power anarchy:




Keith Cress
kcress - http://www.flaminsystems.com

RE: Transformer supply question

I'm glad they knew the safe location for the ladder!

Z

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