Load bank testing - Electrician Talk - Professional Electrical Contractors Forum

heel600 · 08-22-2010, 11:29 PM

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

Bob Badger · 08-22-2010, 11:40 PM

Quote:

Originally Posted by heel600

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

Usually we put that on the vendor we buy the genset from.

Big John · 08-22-2010, 11:45 PM

Quote:

Originally Posted by heel600

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

Rent a load bank. Or contract a company that does load-bank testing and add it to the bid.

The benefit over using the bank instead of a whole bunch of waffle-irons, is that the load bank will give you feedback on how the generator is doing. You can look for peaks, dips, transients, PF problems. All kindsa stuff. Gives you something to show the customer to demonstrate that the generator functions properly.

-John

**MDShunk** · 08-22-2010, 11:50 PM

Quote:

Originally Posted by heel600

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

Load banks that size are typically rented, or you contact a testing company to do that test for you.

micromind · 08-23-2010, 12:39 AM

I think you're better off using a test company, or having the outfit that sold the gen do the test.

One advantage is that once the gen has been commissioned by someone other than you, you're pretty much off the hook if it fails at a later date. Especially if the owner witnesses the test.

**MDShunk** · 08-23-2010, 12:42 AM

If you're talking about the job where the generator was customer supplied, you might try to find out where the generator was coming from (the vendor). Commissioning might be part of their service (sometimes required to be factory commissioned), and you simply have to be on site to pretend like you're doing something and witness the test.

**frenchelectrican** · 08-23-2010, 03:45 AM

Quote:

Originally Posted by heel600

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

Almost all the generators I ran into I useally rent or deal with generator supply centre and many time you can ask for load bank to test the generators.

I have small one { 10 KW unit } not only test on generator but some circuit { both branch and feeder } as well.

The last time I have to rent a load bank due one generator is pretty huge so end up talk to two generator supply centre to send moi the largest one they have and test it but normally they will run thru the test and doucement it.

Merci.
Marc

jwjrw · 08-23-2010, 05:26 AM

The company that we bought the generator from included all set up and testing in their quote. All of them here do it that way.

brian john · 08-23-2010, 07:43 AM

We have load banks 100kw-400kw (2 of each size) above that we rent additional units as needed. The advantage is you can step load from 1kw-30 kw monitoring voltage, current and kw as you load watching response times and performance. We use a line disturbance analyzer for monitoring.

Though a 30 kw load test is unusual, government job?

Bob Badger · 08-23-2010, 08:37 AM

Quote:

Originally Posted by brian john

Though a 30 kw load test is unusual, government job?

I assume you mean that is a low KW test as we often have to load bank much larger generators for commissioning.

We set the roof on fire at one brand new building while doing the load bank test.

We provided the mechanical contractor with the correct thimble to penetrate the roof with the exhaust pipe but they decided it was not needed. The roofing contractor came along later and glued the rubber membrane directly to the exhaust pipe.

Good times indeed.

HAND · 08-23-2010, 08:45 AM

Quote:

Originally Posted by heel600

I'm bidding a job where I need to load test a 30KW genny.

Do I just make up a panel and plug in 15 2000w heaters?

Any suggestions?

You coulld do your own bank if you have patience enough and are going to re-use the thing.
It is just a bank of resistors.
But then you would not know about the gensets ability to start large motors if you did not hook one up.

HAND · 08-23-2010, 08:51 AM

you switch resistors on to the thing until it screams, and you measure the output amps and output volts.
You can also add a kw meter to each leg.

brian john · 08-23-2010, 09:51 AM

What I meant is 30kw is small for a load test and in the past when we have tested units this size 10-100's for commissioning, it was always a government spec. The largest we tested was a 5 meg parallel system.

We retesdted a system after the previous contractor set the shrubs on fire also had an EC set off the sprinklers in a garage.

Like any job some thought has to go into the project more that just letting the unit scream.

John Valdes · 08-23-2010, 11:31 AM

Most motor shops have load testers. The can do a load test at the current you require.
Just an idea?

brian john · 08-23-2010, 01:03 PM

Comrent

http://www.comrent.net/

**MDShunk** · 08-23-2010, 05:19 PM

Related to load banks... are they required to have a calibration sticker?

brian john · 08-23-2010, 06:31 PM

Quote:

Originally Posted by MDShunk

Related to load banks... are they required to have a calibration sticker?

We have been asked that on some jobs, or response has been no, but all our monitoring equipment is calibrated.