2500 Amp Temporary Service

[Umami]

Hello!

I'm new to these forums, so my apologies if I am breaking any rules by posting here.

As you can see in my account I work as a mechanical engineer, but I've been tasked with running down a feasibility study for a project that shouldn't require extremely in-depth knowledge, and is more an issue of codes/feasibility that I hope you all could advise me on. We have a facility and EE on staff who would oversee this work, but they're too busy to take this task on at the moment so here I am! (they'll be involved later on)

Background: We are building a production facility in another state. While the final facility is under construction, we would like to test our RF power systems (including 4x 110V high voltage power supplies, a modulator, a klystron, and a host of other components) in our test facility in Southern California. To run a single RF system, we need approximately 2500A, 480V service, which is substantially higher than what our test facility can provide. We have harmonic filters on our power supplies to keep the power company happy, though our power use will be fairly intermittent while we commission. We're having difficulty getting a transformer/generator/panel set up to connect it to.

We ran into issues with fire/seismic permitting while working with one company to set up a diesel generator. Additionally, our burn rate for fuel would be rather high, creating a logistics problem, so I've been tasked with investigating a temporary pole solution. The power near us is underground, but that doesn't seem to be a problem - it appears there's access to the underground power lines on our property.

I know forums like this can be a wealth of information and experience, so if you don't mind, lay it on me. Tell me why this is a bad idea. Should I spend more time tracking down a different generator rental vendor?

If you are local and interested in a brief consulting gig send me a PM and maybe we can work together.

Thanks!

 

[don_resqcapt19]

The first step would be to talk with your utility to see if their distribution system in that area could handle that much additional load.

 

[Umami]

Yes, thanks. We're in a very large industrial park so I will check with them first, but I don't anticipate difficulty there.

Has anyone encountered issues due to intermittent operation? Are there considerations we need to make there? Ramping, dead loads, etc.

 

[don_resqcapt19]

Yes, thanks. We're in a very large industrial park so I will check with them first, but I don't anticipate difficulty there.

Has anyone encountered issues due to intermittent operation? Are there considerations we need to make there? Ramping, dead loads, etc.

That will be something else to ask the utility. They may not want that much load to come on all at once and may ask for some type of ramping, The power will also probably be very expensive if you are only using that much power infrequently. There will likely be a demand charge that will be substantial.
The actual installation will be pretty straight foreword. Just 2500 amps of wire from the utility transformer to your 2500 amp service switch.

 

[hillbilly1]

I know Sunbelt has trailer mounted temporary switchgear rentals, which would be easier and cheaper than stick building one, but if your previous vendor had issues with seismic requirements, and that generator would have been trailer mounted, they probably wouldn’t allow a trailer mounted switchgear either. Come to think of it, they make portable substations to rent also. The utility would not want to invest in a temporary pad mount.

 

[zbang]

Actually, this might be a question to fire at Sunbelt/Cat-power/Aggreko; they may have most of what you need in a yard somewhere. A portable substation could be ideal, depending on what distribution voltage the power company has around.

Regards fuel, really depends on how long you need that high power. At least with on-site generators, you only have to run them when you need to test. It's also possible that a good rental place would parallel multiple gensets so you can run only one until high power is needed.

Whatever you go for, it'll cost a bit.

 

[Umami]

Come to think of it, they make portable substations to rent also. The utility would not want to invest in a temporary pad mount.

Actually, this might be a question to fire at Sunbelt/Cat-power/Aggreko; they may have most of what you need in a yard somewhere. A portable substation could be ideal, depending on what distribution voltage the power company has around.

That's a good lead, thanks to the both of you.

As for cost, the cost of components under test will dwarf our testing costs, so it's kind of in the wash to be frank. Tapping into grid power will obviously be cheaper and less painful, but you're right that Edison hasn't been the easiest to work with.