Question regarding 50Hz power wiring

Simple answer NO. I had a customer that worked on computer drives, big ones for main frames. He used 120/60 cycle in his labs for everything. Final test was a different situation. We had 120/60, 120/50, 220/60/ and 220/50. He wanted 2 cord sets for the different voltages. We used the same receptacle for both 50/60 cycles. Kept things simpler and less parts to keep track of. When the units were finished the correct cord was attached. I marked the

120/50 with blue paint or tape. The 220/50 was marked in orange. Only had one guy that was color blind so we added printed labels as well. I have even installed 400 cycle equipment in a testing lab. It was run in aluminum conduit and was isolated from every other electrical system by 3 feet, per spec. Wiring was still #12 awg and the panels and breakers were just identified differently.

Yes, the insulation color is different and therefore you must buy special 50 Hz wire in Europe.

No. The peak voltage would be the same irespective of the frequency, for identical RMS voltages. So whatever is suitable for 60Hz at that voltage would also be suitable for 50Hz.

I agree with Gilbert. And it's "irrespective".

I have worked with electrical estimationg design and building maintenance for about a year now. What determines the cabel size it the current flowing through the cable/wiring. Each section of cable must be matched to what its input current. Also you are working with telcoms right?? This probably means that you might need to lay the cables in a certain way so as you dont get EMC interference, also all your components would most definately have to be EMC tested and compliant.

Rob

On Tue, 10 Feb 2004 17:09:11 +0100 Gilbert Mouget wrote: | In article , | dated Tue, 10 Feb 2004 08:56:17 -0500, | estimator, says... | | |> Does the frequency have any effect |> on the insulation or wire size? | | Yes, the insulation color is different and therefore | you must buy special 50 Hz wire in Europe.

I believe you should buy the wire colors as specified by the electric code or standards for the country the installation will be in. A testing lab for products destined for nations with voltages and frequencies different than in the US, but being tested in the US, would certainly involve having special wiring to accomodate powering the devices as they would be powered in the target country. But there is no reason the wiring color has to be that of the target countries. I'm sure no one here believes the wire color will affect the tests. If it ever is an issue, it would be an issue with electrical inspectors. Wire to local standard as much as possible given the application constraints (voltage and frequency in these ranges won't be an issue with US NEC code that I can see). But definitely make sure those wires are marked VERY well. For one thing, 240 volts in the US is a dual pole configuration with neutral center tapped, whereas in Europe, it is a single pole configuration (unless you run 3 phase). It might be necessary to supply the power exactly the way it is done in Europe to make sure the devices under test fail in modes they might fail in Europe, if they are prone to failure for such reasons.

The Lord alerted my mind to the presence of this EVIL article by Harry Bloomfield, and I thusly replied:

Is this true?

Must be, Harry said it was.

You're correct - Harry is right.

Mike

Each outlet on it's own circuit breaker? Wow - that'll be a big panel.

225/390V sounds like it is the transformer output for a 220/380V nominal system? The same cables are used for 50 and 60Hz. You will find many circuit breakers, switches and other accessories are designed for both frequencies. If you go for 400 Hz (airplanes) or 16.7 Hz (trains) it gets a little trickier. :)

/Clas-Henrik