Antique Engines and Old Iron
[Home] - [HELP] - [Forums] - [Library] - [Photo Gallery] - [Groups] - [Classified Ads] - [Subscribe] - [Links] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Vintage Electrical Equipment > Generators & Electric Motors General Discussion > Generac Generators (SEARS, etc.)
Forgot Password? Join Us!

Notices

Generac Generators (SEARS, etc.) Restoring, maintaining and operating Generac generators.

Generac Generators (SEARS, etc.)

SD200 generator need to change output voltage


this thread has 7 replies and has been viewed 379 times

Reply
 
Thread Tools Display Modes
  #1  
Old 03-13-2019, 07:26:19 AM
msquared msquared is offline
Registered
 
Join Date: Jun 2017
Location: Novato, California
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default SD200 generator need to change output voltage

This unit got installed but at the wrong voltage. Model: SD0200GG178.7D18HPSY3 Serial # 3000755715 Alternator # 0000121513
The unit installed came set @ 208VAC but it needs to be 480VAC. Seems nobody tested the unit when installed to see if it would actually run the building loads. So when the client had the first outage the generator started but none of the ATS would transfer to generator power. Seems 2 of the ATS are 480VAC and the one that is 208VAC is going through a stepdown 480-208 xformer before it hits the ATS. I'm hoping that the alternator is a 12 lead type and can be re-strapped to 480. Anyone have a manual on this unit showing the correct connection order.

Thanks Marc
Reply With Quote
Sponsored Links
  #2  
Old 03-13-2019, 03:57:04 PM
Gentek Gentek is offline
Registered
 
Join Date: Jan 2019
Location: Clawson, Michigan
Posts: 9
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: SD200 generator need to change output voltage

I'm not on the Industrial side so take this for what it's worth, but in a lot of cases, re-configuring the output voltage of a unit can void the warranty. This might be something that you want to get a Generac Industrial Dealer involved in so that it can properly be re-configured. It will require re-programming the controller as well which is limited access to Industrial dealers only also.
Reply With Quote
  #3  
Old 03-13-2019, 08:06:38 PM
pegasuspinto pegasuspinto is offline
Registered-III
 
Join Date: Oct 2006
Location: Floyd, AR, USA
Posts: 2,915
Thanks: 337
Thanked 1,394 Times in 907 Posts
Default Re: SD200 generator need to change output voltage

First, slap the mess out of whoever designed, implemented, and approved that hot mess. Remind them they are lucky they didn't kill anyone too.

I'm going to take your description for granted, since I can't verify. If I was there I would personally take the place to bits and trace out and document all the deficiencies, as it just seems likely this can't be the whole story......

Your generator was first put online about 2.5 years ago and has been out of warranty for the last several months.

My assumption is this generator was bought used?

IMHO you should contact your local INDUSTRIAL Generac Dealer, you can find them on www.generac.com, and also contact a qualified electrical contractor, both of them early on. There will need to be major changes done, and this is a place where qualified people and good planning will save you money and grief.

First, you will have to bring the industrial dealer in the loop so the generator can be reconfigured. The generator will need to be rewired for 480v, the breaker(s) will need to be replaced with the correct amperage, and the computer will need either a new XML (personality key) or the existing one modified. Changing or modifying the XML is not for amateurs!

Each ATS should have it's own breaker rated at no more then the amperage rating of that ATS. The combination of those breakers should not be able to overload the generator (about 300 amps). OR you can replace the generator breaker with a 300 amp breaker and add a distribution panel to protect the ATS.

I'm assuming you really have 2 of the 480 ATS, fed 480 utility and needing 480 from the generator. Not much may need changing there. But your 208 ATS fed from a transformer will need major revisions. I'm assuming you have a 480 to 208 feeding the utility side of this ATS and the generator side is fed directly. IF you are lucky, you have one of the ATS that can be easily reconfigured for 480. MOVE the step down transformer to the load side of the ATS, reconfigure or replace the ATS as 480 and feed the ATS 480 on both the utility and gen sides. DO NOT feed a step down transformer directly from the generator output, it's not good for them.

Don't forget to verify voltage and phase rotation on both utility and gen all 3 ATS BEFORE the transfer test, and don't call it complete until you do a load drop test and make sure the whole shooting match works.
Reply With Quote
  #4  
Old 03-14-2019, 06:47:23 AM
msquared msquared is offline
Registered
 
Join Date: Jun 2017
Location: Novato, California
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: SD200 generator need to change output voltage

Quote:
Originally Posted by pegasuspinto View Post
First, slap the mess out of whoever designed, implemented, and approved that hot mess. Remind them they are lucky they didn't kill anyone too.

I'm going to take your description for granted, since I can't verify. If I was there I would personally take the place to bits and trace out and document all the deficiencies, as it just seems likely this can't be the whole story......

Your generator was first put online about 2.5 years ago and has been out of warranty for the last several months.

My assumption is this generator was bought used?

IMHO you should contact your local INDUSTRIAL Generac Dealer, you can find them on www.generac.com, and also contact a qualified electrical contractor, both of them early on. There will need to be major changes done, and this is a place where qualified people and good planning will save you money and grief.

First, you will have to bring the industrial dealer in the loop so the generator can be reconfigured. The generator will need to be rewired for 480v, the breaker(s) will need to be replaced with the correct amperage, and the computer will need either a new XML (personality key) or the existing one modified. Changing or modifying the XML is not for amateurs!

Each ATS should have it's own breaker rated at no more then the amperage rating of that ATS. The combination of those breakers should not be able to overload the generator (about 300 amps). OR you can replace the generator breaker with a 300 amp breaker and add a distribution panel to protect the ATS.

I'm assuming you really have 2 of the 480 ATS, fed 480 utility and needing 480 from the generator. Not much may need changing there. But your 208 ATS fed from a transformer will need major revisions. I'm assuming you have a 480 to 208 feeding the utility side of this ATS and the generator side is fed directly. IF you are lucky, you have one of the ATS that can be easily reconfigured for 480. MOVE the step down transformer to the load side of the ATS, reconfigure or replace the ATS as 480 and feed the ATS 480 on both the utility and gen sides. DO NOT feed a step down transformer directly from the generator output, it's not good for them.

Don't forget to verify voltage and phase rotation on both utility and gen all 3 ATS BEFORE the transfer test, and don't call it complete until you do a load drop test and make sure the whole shooting match works.
First: The generator was installed new for a school district...low bidder wins all( all that documentation is now being gone over with a fine tooth comb). Not impressed with the install work, idiots couldn't afford phase tape, single wrap of white tape with sharpie lettering "leg 1" "Leg 2"... Not impressed with Generac either. The unit came with 2 breakers a 650Amp MB and a 200Amp MB all feed from the alternator. So the 650A MB goes to a 480VAC distribution panel from there one breaker feeds a stepdown transformer which feed the E-load side of the 208VAC ATS. From the same 480VAC distro panel another breaker feeds directly to the e-load side of a 480VAC rated ATS. The 200A MB goes to another 480VAC ATS.
I know that the main breakers will need to changed out and the controller reprogrammed to accept the new voltage. I am a licensed electrical contract.
I just want to know that Generac hasn't done something odd so I can't re-strap this unit. Just trying to give the school district some options to solve the problem in the easiest manner, Couple of breakers and some dealer time to re-program controller going to be cheaper than a bunch of stepup Xformers.
Reply With Quote
  #5  
Old 03-14-2019, 07:39:40 AM
pegasuspinto pegasuspinto is offline
Registered-III
 
Join Date: Oct 2006
Location: Floyd, AR, USA
Posts: 2,915
Thanks: 337
Thanked 1,394 Times in 907 Posts
Default Re: SD200 generator need to change output voltage

Well, in all honesty, Generac didn't do anything wrong. Hate to get into too many details as it may be next a hot legal mess, but the error should of been caught at installation, commissioning, and final testing, which comes down to the locals.

It's very, very bad practice to feed a transformer straight off of the generator. On startup and shutdown, as the frequency winds up and down, they will fight each other electrically. Don't be shocked if the generator and/or the transformer are eventually damaged. Also makes me wonder, are all the ATS fed off of a common utility feed? Were 4 pole (neutral switched) ATS installed, or should they be 4 pole units?

Like I said, the gen can almost certainly be restrapped and reprogrammed, but you will need the industrial dealer to reprogram the unit. The access for that ability is restricted by a crypto key given to industrial techs. (I don't make the rules, just live by them). I would suggest you call Generac directly, you might find them to be very helpful.
Reply With Quote
  #6  
Old 03-14-2019, 11:50:52 AM
Vanman Vanman is offline
Subscriber
 
Join Date: Aug 2011
Location: Mission Viejo, California
Posts: 5,711
Thanks: 8,916
Thanked 2,618 Times in 1,769 Posts
Default Re: SD200 generator need to change output voltage

Have to agree with everything said here except a transformer connected to a generator being bad for either.

Bad practice to have one on the generator and one on the utility to then supply an ATS, yes, since you're buying two where only one is needed.

As the generator slows down, the under frequency roll off feature of the AVR will proportionally lower the voltage. Transformers can successfully operate at radically different frequencies if the voltage is also changed in proportion. And even if it did saturate a bit for a second or two it's going to be far less current and than when thrown on the line.

When the generator starts, the voltage and frequency will ramp up. Like a soft start for a transformer.

Keith
Reply With Quote
  #7  
Old 03-14-2019, 02:56:07 PM
pegasuspinto pegasuspinto is offline
Registered-III
 
Join Date: Oct 2006
Location: Floyd, AR, USA
Posts: 2,915
Thanks: 337
Thanked 1,394 Times in 907 Posts
Default Re: SD200 generator need to change output voltage

You obviously haven't heard all the foul noises and commotion that a large generator and large transformer make when bolted together. At low frequencies, a transformer starts looking more and more like a dead short. The current flow is very high even at low voltages. By no means does low frequency 'soft start' a transformer, it's NOT a motor.
Reply With Quote
  #8  
Old 03-14-2019, 04:12:21 PM
Vanman Vanman is offline
Subscriber
 
Join Date: Aug 2011
Location: Mission Viejo, California
Posts: 5,711
Thanks: 8,916
Thanked 2,618 Times in 1,769 Posts
Default Re: SD200 generator need to change output voltage

No, that's true, I have not experienced that. But I also just can't wrap my mind around it. The reason I can't see it being a problem is because a generator generally cannot produce a higher voltage to frequency ratio than it's rating. So a 480 volt, 60 cycle generator idling at 15 cycles would produce 120 volts (less if it's not separately excited). A 480 volt, 60 cycle transformer would work perfectly well connected to a 120 volt, 15 cycle source.

But, I searched Google to see what I may have missed. There's a discussion about it here: http://forums.mikeholt.com/showthread.php?t=139130
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
Onan Generator 5.0 KQ-3E/1A runs but no voltage output Morgan the Priate Onan Generators 3 04-26-2018 01:47:49 AM
Winco 75 kw generator help no voltage output Weldor77 Generators & Electric Motors General Discussion 4 06-18-2014 08:30:15 AM
Autolite generator voltage change question Kenny Short Antique Farm Tractors 1 05-19-2009 10:22:03 AM
Dayton 5000w generator, no AC output voltage dfb Generac Generators (SEARS, etc.) 3 05-13-2009 08:04:12 AM
DC Generators -change voltage output? John Marrais Generators & Electric Motors General Discussion 12 07-04-2008 02:41:50 PM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 03:03:35 AM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2019 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277