I am an a/c guy by trade and some knowlegde with controls and electricity.I am state certified in HVAC.In my area generators are very popular lately due to hurricanes.My wifes aunt has been after me to install one for her so I did today.I talked with my electrican freinds before the installation to make sure of the best and easiest way to wire in the auto switch panel.To make a long story short I fried a tv, 3 power strips and a microwave on startup.I checked for proper voltage and hertz before loading the generator.I had 247v and 62 hertz.I wired the main sub panel 60 amp breaker and the 40 amp a/c breaker in.I had not paperwork with the generator somebody had taken it from the box.Im not sure what to do next are what to check.Any of you guys with experience with generators thoughts would be great.

 

My next door neighbor is a electrician for Al. River Pulp. Will try to ask him tomorrow evening about your problem.

Kip
Bay Minette

 

I am a SR. RF Engineer with a regional wireless carrier. We have Diesel Generac's on some of our sites and mobile Generac's. Yes you have to be carefull when you wire them up. Had someone wire the hoc on the outside of the building wrong and it blew the breaker panel off the wall. Not sure which one you have. Is it diesel or propane?

 

Its natural gas 12kw.I know the wiring is correct just not sure what is going on with the voltage in the house scared to switch the load to the generator now.I gonna get the install manual tomorrow that somebody removed from the box.

 

I've installed a few for our customers. I am an electrician as well as an electrical instructor.

My first question is did this happen while under generator power? If yes, there were no issues while under service power I presume?

My first question is the integrity of your neutral- is it wired correctly? You wrote you have 247V at 62Hz, which is correct with no load, phase to phase. But, do you have around 123 or so on each phase to ground/neutral? The neutral from the generator should be continuously connected with the service neutral at the transfer, correct?

If this is correct, is the panel the one with the Homeline breakers?

If this is incorrect, I need some more information.

Are you able to email me pictures?

 

There are two models; natural gas and propane. The KW output is slightly differant for each due to the BTU differance between the two gases. Anyway, I see this post now. So, this happened while under house power, but only the circuts moved to the generator panel?

 

I would suggest the same thing. Check your wireing. I have seem them get installed incorrectly also and what normally happens is they have a 120volt line on the ground. It will show you 240 volts from one leg to ground. You should see 120 volts from one leg to ground.( Check both 120volt lines one at a time). If you check from hot to hot then you will read 240 volts. How did you test it? They blew the ballast out of the lights when it happened to me about 6 years ago when I was a Tech. That was the only thing I turned on thank goodness. I when straight to the transfer switch and tested their wireing. Wrong,Wrong,Wrong. Had it fixed in about 5 minutes just had no lights.

 

I will check the neutral closely.My tech hooked up the grounds while I hooked up the gas lines.We used the generac outdoor auto switch.We used a square D panel between the main and the switch panel.I remember that the ground was hooked from the generator to the switch panel and the squareD panel.I will check to make sure it is terminated to the main.I will check each leg to neautral also.I dont have pics but can get them tomorrow if need be.Thanks

 

Sounds good. The way we have our permanent ones wired is off the meter head to the transfer switch, then to the outside of the buildings disconnect, then to the main breaker box in the building. That way if we lose power it automaticaly starts ups and then transfers. Of coarse we have contacts wired for alarming purposes to the BTS equipment so we will have an alarm in our switching equipment.

 

One thing that might have happened is if your neutral line is open and you have a big load on one phase which will throw all the voltage to the other phase. Been there, done that.

Edwin

 

Sounds like you might of had a Hi-POT condition from an open neutral.

 

Bama dude,

While I am not a true electrician (I am an electronics tech) I am very familiar with these generators. You say you have a 12kW natural gas or propane (You can use either with this generator, you have to set the gas regulator accordingly) made by Generac. I just want to let you know of potential problems you may have with it.

I have 2 of those 12kW gensets that provide backup power to 2 seperate remote communiction sites. They generators that we have are made by Generac sold as thier Guardian series generators. These units have a 2 cylinder V-twin style engine that drives the genset. From our expierience with them I firmly believe that these things are garbage.

1. These gensets are fairly noisy, even with the lid shut. Not a problem for a remote comms site, but could be a nuiscance in a residential setting. They run at 3600 RPM so they are fairly noisy.

2. These things are terrible in fuel economy. Both our remote sites have a 500 gallon LPG tank setup to feed the generators. They are setup for vapor withdrawal so the tank feed the generator propane gas instead of LPG. This means the tank can only be filled to 85% for a sufficient gas layer to form at the top of the tank. This gives us 425 gallons of usable fuel for the generators. That 425 gallons will only last for maybe 12.5 days of continuous use before it runs out. Crappy economy for such a small engine. Since your generator is probably running of a gas main instead of a tank, 1 gallon of LPG=36.39 cubic ft. of propane gas @ 60°F.

3. Another downside to this generator is its engine. Its air cooled. A lot of air cooled engine don't like running for extended periods, espescially in tight enclosures. What happens is since they run hotter than liquid cooled engines, they tend to slowly burn off its oil supply. This won't happen with periodic use but if it run continuous for days it will burn off enough oil to trip the low oil shutdown. Takes about 3-4 days of continuous running for this to happen. When it happens with ours I have to drive up to the site and refill and reset the system.

4. My biggest proble with them is the quality of the system in general. One of our units had its stator fail before it even logged 50 hours on its time meter (we installed hour meters on ours). Not even one year old and it had failed. When I put the megger on the windings the entire stator failed the test, with one set of windings being completely shorted.

Our other set has its own problems. When it runs its sputters like the plugs are bad, but the magneto is not firing one cylinder properly. Another pitfall is the battery charger. It is set too high (14.2 volts) and overcharges the battery. We had a battery explode because of this.

Overall, my opinion of these things is very low. Ours gave us more problems than they solved. Hope yours fare better.

 

Just a silly question, is engine speed correct?

 

Get the #'s off the nameplate and download the right dwgs and try again.
http://www.guardiangenerators.com/pr...an_manuals.asp
I agree with Edwin and Jim.. sounds like an open neutral. That'll sure fry stuff..
K.

 

Found the problem today The neutral from the generator was hooked the the ground lug in the generator instead of the neutral lug.Generator creates its own neutral on power interuption.I should have looked closer,of course the installers manual would have been nice.Thanks for all you guys help.