100Hz derating??

[jsharvey]

Is there any additional derating required when you're using 100Hz as opposed to the standard 60Hz. Yes, we're on the rail road stuff again.

Jim

 

[dereckbc]

Re: 100Hz derating??

Not that I am aware of. Do not believe NEC applies to railroad. The only real design difference would be slightly higher voltage drop.

 

[jsharvey]

Re: 100Hz derating??

I understand that this, the 100Hz, is definitely not covered by NEC, but since we use the same wire, devices and panels that would normally be used in residential/commercial work, I didn't want any surprises.

Thanks
Jim

 

[gazzoo]

Re: 100Hz derating??

You are increasing the Inductive Reactance or Ohms 67%. Circuit impedance would be considerable, larger conductors or reduced output in load could keep it within safe standards. never introduce a nonlinear load. Formula 2xPIxFxL=Ohms Known as Lenz Law.

 

[dereckbc]

Re: 100Hz derating??

Jim, I do not think you are in for any big surprises. You might encounter slightly higher voltage drop on long or heavily loaded circuits.

If this was for aircraft or some older computer systems employing 400 Hz systems you would need to base conductor sizes on voltage drop rather than OCPD. But at 100 Hz the difference is small, and shouldn't be of too much concern.

If you wanted too you could up-size the conductors to the next size on say runs over 50 feet, but that is really adesign issue rather than code.

What kind of cable insulation are you going to use? If the application is going to be exposed to diesel fuel or other chemicals, I would be more concerned with insulation types.

[ January 31, 2004, 11:36 AM: Message edited by: dereckbc ]