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Topic: Not switching to AC voltage with generator (Read 1817 times) previous topic - next topic
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Re: Not switching to AC voltage with generator
Reply #50 –
Something else to consider: it's possible you may have a "peak       reading voltmeter". 120 volts that we normally associate with our       "normal" ac readings is an RMS value, RMS meaning root meas       square. It just so happens that RMS times the square root of 2       equal peak value. In this case 120 x 1.414 = 169.95 (or something       like that). My suggestion would be to read the voltage with       another meter, just to confirm the RMS value is actually 170       volts. You may actually have nothing to fix.

Ken

On 2/19/2021 5:49 PM, tedeboy via LDO wrote:

Quote

 
Quote

On: Fri Feb 19, 2021 hbn7hj Wrote:

Just to add to your day that ATS switch is no longer made.

It is a Parallax Power Supply Auto Gen Transfer Switch ATS 301 30amp 120VAC.

You may be able to find one. I did. The circuit breakers may have to be removed to get to the attaching screws.

I would transfer the new switch to the old box, I think.

Here is one. It says 37 in stock!

[Parallax ATS301 30 Amp 120 Volt Automatic Line/generator Transfer Switch -...](Froxlor Server Management Panel .com/products/parallax-ats301-30-amp-120-volt-automatic-line-generator-transfer-switch?gclid=Cj0KCQiA4L2BBhCvARIsAO0SBdZRJKluiIylIvF2Z9rG_4WNbIFFmrO2xw3hvwtknCLEuXEqlKCI1_YaAspJEALw_wcB)

It is possible that the switch you get won't match your's but the picture does.

Amazon's picture does not. Might be a bit of a crapshoot. Worst case transfer the new parts to the old box. 
 


I think I need to solve the issue of why the generator outputting 170 VAC first. I tested it at the circuit breaker on the generator itself. 
I want to figure out how to test the voltage regulator now (part 305-0809-01).

1995 23.5 Twin King


						

					
					

							
Former 2009 MB owner

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #51 – 
							

							

						

						
Quote from: Ken and Joyce  -  
Something else to consider: it's possible you may have a "peak       reading voltmeter". 120 volts that we normally associate with our       "normal" ac readings is an RMS value, RMS meaning root meas       square. It just so happens that RMS times the square root of 2       equal peak value. In this case 120 x 1.414 = 169.95 (or something       like that). My suggestion would be to read the voltage with       another meter, just to confirm the RMS value is actually 170       volts. You may actually have nothing to fix.

Ken

On 2/19/2021 5:49 PM, tedeboy via LDO wrote:
 


I think I need to solve the issue of why the generator outputting 170 VAC first. I tested it at the circuit breaker on the generator itself. 
I want to figure out how to test the voltage regulator now (part 305-0809-01).

1995 23.5 Twin King



I did confirm the accuracy of my meter.
I wish it measured frequency.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #52 – 
							

							

						

						
Hi Ted;  I went to Flight Systems for help. https://www.flightsystems.com/pdf/onan-rv-troubleshooting-guide.pdf    On page 6 midway, they have frequent questions/ answers concerning too high a voltage.  They say that the regulator board could be bad, but first check connections, especially pin 2.   Sounds like that is worth a try.     RonB
						

					
					

							
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #53 – 
							

							

						

						
Quote from: RonB  -  
Hi Ted;  I went to Flight Systems for help. https://www.flightsystems.com/pdf/onan-rv-troubleshooting-guide.pdf    On page 6 midway, they have frequent questions/ answers concerning too high a voltage.  They say that the regulator board could be bad, but first check connections, especially pin 2.   Sounds like that is worth a try.     RonB

Thank you.
I also sent them an email with my issue.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #54 – 
							

							

						

						
UPDATE

I followed this video for testing.

MEASURING YOUR GENERATOR WINDINGS

I then called Flight Systems with the results.
They are so helpful.

Pins 9 and 10 test was not good.
I've got new brushes and springs coming plus I need to shine up the rings.

Chances are my regulator is damaged they said by the fluctuations from the brushes not making good contact.

That video is very helpful.
						

					
					

							
2021 Mid Bath

						

					

				

				

				 	
				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #55 – 
							

							

						

						
Normally, monthly generator runs are all it takes to keep the slip rings clean, the spring-loaded brushes rub the slip rings and remove minor surface contamination.
If me, I would be tempted to let the generator run for a long period, an hour or more, and then remeasure the resistance.
This may be enough to eliminate the problem, it doesn't cost much to do, other than the fuel used.
I can't see where this would cause any more damage. 

Cleaning the slip rings and replacing the brushes will require dropping the generator, a big task unless you are equipped to do such work. I suggest using a transmission jack to lower the genset.

Larry
						

					
					

							
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #56 – 
							

							

						

						
Quote from: Larry W  -  

Cleaning the slip rings and replacing the brushes will require dropping the generator, a big task unless you are equipped to do such work. I suggest using a transmission jack to lower the genset.

Larry

Fortunately I got to my brush assembly and removed it without dropping the generator (or one of the mounting screws LOL). This also exposed the rings for which I have a Flight Systems "Slick Stick" in order to shine them up with.

						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #57 – 
							

							

						

						
Quote from: tedeboy  -  
Fortunately I got to my brush assembly and removed it without dropping the generator (or one of the mounting screws LOL). This also exposed the rings for which I have a Flight Systems "Slick Stick" in order to shine them up with.

I guess the Emerald generators have better access than the newer Onans.
Glad it is simpler than I thought.

Larry

						

					
					

							
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #58 – 
							

							

						

						
Quote from: Larry W  -  
I guess the Emerald generators have better access than the newer Onans.
Glad it is simpler than I thought.

Larry


I removed the air filter housing and there it was.

The most nerve racking part was being careful to not drop one of the mounting screws. 😅




						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #59 – 
							

							

						

						
Update:

Replaced brushes and springs.
Shined the rings.
That brought my stationary ohm reading into tolerance on the 9/10 pins at 25 ohms.

Problem is during spinning the ohms flucuate from 0.00 to OL at those same pins.
I think I have a short in the rotor.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #60 – 
							

							

						

						
Hi Ted;  That may be normal; I'm not sure that you are using the ohm meter in it's most sensitive range.  You should at least be reading about 1-2 ohms for the resistance of the meter leads.  A shorted rotor would never generate 170 V AC.  The pin 9 to pin 10 resistance, if that is across the rotor winding, fits the 25 ohm spec. If the slip rings and brushes are connecting well, then the reading shouldn't fluctuate much.
    What happens when you try running it now?  And the voltage regulator is suspect; it controls how much current flows in the rotor, which determines the voltage output of the stator.  The stator provides the 4 KW output to the coach. ( and the 'excitation' voltage to the rotor). 
     The rotor could have damaged insulation or connections inside the rotor that move, or hit the stator iron laminations during rotation.  Always a chance to pick up rocks with the fan during motion of the RV. RonB
						

					
					

							
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #61 – 
							

							

						

						
Quote from: RonB  -  
Hi Ted;  That may be normal; I'm not sure that you are using the ohm meter in it's most sensitive range.  You should at least be reading about 1-2 ohms for the resistance of the meter leads.  A shorted rotor would never generate 170 V AC.  The pin 9 to pin 10 resistance, if that is across the rotor winding, fits the 25 ohm spec. If the slip rings and brushes are connecting well, then the reading shouldn't fluctuate much.
    What happens when you try running it now?  ...

I am in touch with Tyler at Flight Systems. He said that ohm reading shouldn't fluctuate much during rotation. They say if it does drop then bad windings or short in the rotor.

My goal is to make sure everything before the voltage regulator tests good prior to installing a new regulator. I want to make sure I don't ruin a new regulator.

Measuring Generator Windings
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #62 – 
							

							

						

						
Hi Ted; Thanks for that Flight Systems video link.   Before the repair price gets too high, you could upgrade to the newer MicroQuiet that newer LD's have.  RV GENERATOR-ONAN MICROQUIET 4000 WATTS-GAS|55-0050.  I would expect that it would fit in the same space.   The muffler is internal, and re-selling your '95 TK might be easier if or when your new MB arrives.  We live in the same climate, and have about the same age Emeralds +, with similar hours. (mine has about 140 hours).    RonB
						

					
					

							
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #63 – 
							

							

						

						
Quote from: RonB  -  
Hi Ted; Thanks for that Flight Systems video link.   Before the repair price gets too high, you could upgrade to the newer MicroQuiet that newer LD's have.  RV GENERATOR-ONAN MICROQUIET 4000 WATTS-GAS|55-0050.  I would expect that it would fit in the same space.   The muffler is internal, and re-selling your '95 TK might be easier if or when your new MB arrives.  We live in the same climate, and have about the same age Emeralds +, with similar hours. (mine has about 140 hours).    RonB

Very good point Ron.
My repair costs need to be factored in for sure. Anything over a certain amount and new is preferred. 
I'm tempted to replace the entire generator anyway.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #64 – 
							

							

						

						
Quote from: tedeboy  -  
Very good point Ron.
My repair costs need to be factored in for sure. Anything over a certain amount and new is preferred. 
I'm tempted to replace the entire generator anyway.

I hate to open this can of worms, but here goes something to think about.

If I didn't already have a working generator, and was looking at the cost of buying a new one, I would at least consider spending the same money on solar plus lithium batteries plus inverter.  

I'm not sure that the answer would be the same for everyone, but I think technology and prices are approaching the point where not having a generator could be the right answer for some.  

This is based on a price of $4000-$5000 for a new Onan 4000 installed.  There are cheaper options out there for sure.     

Rich

						

					
					

							
2003 MB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #65 – 
							

							

						

						
Quote from: tedeboy  -  
Very good point Ron.
My repair costs need to be factored in for sure. Anything over a certain amount and new is preferred. 
I'm tempted to replace the entire generator anyway.

Don't you have new LD on order?
I think you will hesitate when you see how much installing a newer generator is going to cost. The old Emeralds are not available anymore, requiring a newer model that fits very differently.
Something to research.

Larry


						

					
					

							
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #66 – 
							

							

						

						
Quote from: Larry W  -  
Don't you have new LD on order?
I think you will hesitate when you see how much installing a newer generator is going to cost. The old Emeralds are not available anymore, requiring a newer model that fits very differently.
Something to research.

Larry



We haven't gotten "the call" but we are in the list. I want this TK to be in good working order before she goes to market.

By all indications I have a "flying short" in the rotor. Just talked with Flight Systems and another repair guy.

I'll need to drop and replace the rotor. Unfortunately I don't have the 
jack to do this nor the strength by myself. I'll need to find a way.

Rotor plus the new circuit breaker plus a new voltage regulator and I'm close to $1,000 or more so far.

Such is the life of a motorhome owner.

						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #67 – 
							

							

						

						
Quote from: tedeboy  -  
We haven't gotten "the call" but we are in the list. I want this TK to be in good working order before she goes to market.
By all indications, I have a "flying short" in the rotor. Just talked with Flight Systems and another repair guy.

I'll need to drop and replace the rotor.
Rotor plus the new circuit breaker plus a new voltage regulator and I'm close to $1,000 or more so far.

it will be cheaper to repair than to replace.
A transmission jack is handy for removing generators. An equipped generator shop can drop it in just a few minutes.

Larry
						

					
					

							
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #68 – 
							

							

						

						
Quote from: Larry W  -  
it will be cheaper to repair than to replace.
A transmission jack is handy for removing generators. An equipped generator shop can drop it in just a few minutes.

Larry

I got a quote from Quality RV in El Cajon, CA.

$800 new rotor windings.
$163 per hour @ 4 hours.
$300 new regulator.

It'll be $2,000 at least.
But yes, cheaper.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #69 – 
							

							

						

						
Rich,

I’ve only had my solar system with 800+ watts of solar and 5 Battleborns for a short time but I soon realized that the generator still plays an important role in keeping the batteries charged during low angled sun and cloudy days.

That being said it takes less generator time to go from 40% charge to 100%. 

I kinda cringe when I hear that RVers have dumped the genny because they increased their solar/battery capacity.

I prefer to cover all my bases. That’s just me.

Kent
						

					
					

							
2015 27' RB "MissB.Haven"

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #70 – 
							

							

						

						
Quote from: Kent Heckethorn  -  
Rich,

I’ve only had my solar system with 800+ watts of solar and 5 Battleborns for a short time but I soon realized that the generator still plays an important role in keeping the batteries charged during low angled sun and cloudy days.

That being said it takes less generator time to go from 40% charge to 100%. 

I kinda cringe when I hear that RVers have dumped the genny because they increased their solar/battery capacity.

I prefer to cover all my bases. That’s just me.

Kent

Agree.  It depends on your usage.  

I'm curious to know which one you would choose if you had $5k to spend and only wanted to pick only one due to either space or budget limits.

I've thought about the question in terms of building a trailer and outfitting it from scratch, but having a failed generator puts you in a similar situation.

Rich


						

					
					

							
2003 MB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #71 – 
							

							

						

						
Quote from: rich  -  
Agree.  It depends on your usage.  

I'm curious to know which one you would choose if you had $5k to spend and only wanted to pick only one due to either space or budget limits.

I've thought about the question in terms of building a trailer and outfitting it from scratch, but having a failed generator puts you in a similar situation.

Rich



We were in a hot wind storm at Lake Powell. I'm thankful we had a generator for the A/C. I'm not sure what we would have done. I guess we'd would have been forced to leave.
						

					
					

							
2021 Mid Bath

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #72 – 
							

							

						

						
Quote from: Kent Heckethorn  -  
I’ve only had my solar system with 800+ watts of solar and 5 Battleborns for a short time but I soon realized that the generator still plays an important role in keeping the batteries charged during low angled sun and cloudy days.
That being said it takes less generator time to go from 40% charge to 100%. 
I kinda cringe when I hear that RVers have dumped the genny because they increased their solar/battery capacity.
I prefer to cover all my bases. That’s just me

Short, winter days, cloudy days, or trees all can restrict or eliminate any solar gains, sometimes for days. Last summer, while camped at Mammoth, the combination of some tree and cloudy days eliminated much or any solar gain. After a few days, a generator run is a necessity. 
Our 1983 LD did not have a generator and it was a real problem when dry camping for more than a couple of days. The 1983 LD only had a 120-watt of solar and it was in the pre-LED days. If the coach battery was deeply discharged, running the engine was the only way to recharge it quickly, moving every two to three days became our way of traveling. 
More battery capacity and increased solar extend the days you can camp in no solar gain places.

With the adaption of lithium batteries, a 120-VAC battery charger that can fully utilize the generator's 30-amp output would be a good addition to minimize generator fun time, if and when they are available. 

Larry




						

					
					

							
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #73 – 
							

							

						

						
Hi Ted. That RV place in El Cajon probably shops it out to a generator repair place. An advantage you have, is that you can go to where the repair place is.  There are repaired ones available, but of unknown age and overall condition.  Cummins Onan Emerald GenSet 4000 Watt RV Generator 4 kW | eBay   
   The $2k is sounding better for hassle factor. I'd shop around in the industrial L.A. region.  Arizona, Nevada might be worth the trip there.  RonB
						

					
					

							
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

						

					

				

				

				

					
					
					

						

						
							Re: Not switching to AC voltage with generator
							
								
							
							

								Reply #74 – 
							

							

						

						
Quote from: RonB  -  
   The $2k is sounding better for hassle factor. I'd shop around in the industrial L.A. region.  Arizona, Nevada might be worth the trip there.  RonB

I've been informed that Quality RV and the Onan/Cummins dealer in San Diego County are the two best in town.
Quality RV isn't as expensive and get better reviews for what that is worth.

I'm not dropping this thing.

It's looking like I'm going to bite the bullet and take it in.

						

					
					

							
2021 Mid Bath