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Onan 3 wire to 4 wire Transfer Switch Recepticle


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  #21  
Old 02-23-2017, 12:18:13 AM
Steve Dawkins Steve Dawkins is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

I believe your transfer switch has six switches that are three position, SPDT switches. It may also have six miniature circuit breakers that have pop out buttons for resets. If your switches are marked 1-6 (some manufacturers use letter designations instead of numbers) then you should have six red wires and six black wires that are marked 1-6. Switch #1 should have a red and black wire that are also marked "1". If this transfer switch is like all other manual transfer switches that I have installed, this is the way it should be wired:

1. Select a single pole circuit breaker in your house panel that you want that circuit to operate on generator. it can be a 15 or 20 amp breaker, but no larger than 20 amps.
2. Disconnect the wire from the load side of the breaker. Connect the load wire that you removed from the breaker to the black #1 wire from the transfer switch. After making the connection, hold the wirenut in one hand, and tug on the black stranded wire with your other hand to make sure you have a good joint. Solid and stranded wire connections can be tricky.
3. Connect the red #1 wire to the circuit breaker. After connecting it, tug on the red wire to make sure it is securely connected to the lug on the breaker. The transfer switch wires are stranded, and house wiring is solid. Stranded wire works better with some manufacturers circuit breakers than it does with others. Square D and Cutler Hammer type CH breakers hold stranded wire very well, because they have a clamping type washer on the set screw. That washer holds the stranded wire securely. Other manufacturers such as Siemens, GE and others have a set screw that bites directly on the wire. They work well with solid wire, but don't clamp very well on stranded.
Repeat steps 1-3 for the remaining five switches.
4. Connect the white neutral and green ground wires to your panel.

FYI, the red and black wires that connect to the twist-lock inlet plug don't correlate to the red and black wires that are numbered 1-6. The red & black from the inlet plug are for incoming power from the generator. They connect to the mini breakers in the transfer switch, which in turn connect to the GENERATOR side of each switch. The red numbered wires that connect to the circuit breakers in your panel will be isolated from the other wiring inside the transfer switch. Those red wires bring utility power from the house circuit breakers to the UTILITY side of each transfer switch. Only the black numbered wires will connect to generator power. Hope this makes sense.

I don't know if you can post photos on this site yet, but pics of your transfer switch would be helpful. You may have something totally different from what I am envisioning.
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  #22  
Old 02-23-2017, 03:04:07 AM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Quote:
Originally Posted by Steve Dawkins View Post
I believe your transfer switch has six switches that are three position, SPDT switches. It may also have six miniature circuit breakers that have pop out buttons for resets. If your switches are marked 1-6 (some manufacturers use letter designations instead of numbers) then you should have six red wires and six black wires that are marked 1-6. Switch #1 should have a red and black wire that are also marked "1". If this transfer switch is like all other manual transfer switches that I have installed, this is the way it should be wired:

1. Select a single pole circuit breaker in your house panel that you want that circuit to operate on generator. it can be a 15 or 20 amp breaker, but no larger than 20 amps.
2. Disconnect the wire from the load side of the breaker. Connect the load wire that you removed from the breaker to the black #1 wire from the transfer switch. After making the connection, hold the wirenut in one hand, and tug on the black stranded wire with your other hand to make sure you have a good joint. Solid and stranded wire connections can be tricky.
3. Connect the red #1 wire to the circuit breaker. After connecting it, tug on the red wire to make sure it is securely connected to the lug on the breaker. The transfer switch wires are stranded, and house wiring is solid. Stranded wire works better with some manufacturers circuit breakers than it does with others. Square D and Cutler Hammer type CH breakers hold stranded wire very well, because they have a clamping type washer on the set screw. That washer holds the stranded wire securely. Other manufacturers such as Siemens, GE and others have a set screw that bites directly on the wire. They work well with solid wire, but don't clamp very well on stranded.
Repeat steps 1-3 for the remaining five switches.
4. Connect the white neutral and green ground wires to your panel.

FYI, the red and black wires that connect to the twist-lock inlet plug don't correlate to the red and black wires that are numbered 1-6. The red & black from the inlet plug are for incoming power from the generator. They connect to the mini breakers in the transfer switch, which in turn connect to the GENERATOR side of each switch. The red numbered wires that connect to the circuit breakers in your panel will be isolated from the other wiring inside the transfer switch. Those red wires bring utility power from the house circuit breakers to the UTILITY side of each transfer switch. Only the black numbered wires will connect to generator power. Hope this makes sense.

I don't know if you can post photos on this site yet, but pics of your transfer switch would be helpful. You may have something totally different from what I am envisioning.
You are very right, You described mine accurately and your install instructions are right on the money. Now I have to get two 120v hots off of my Onan genset 5.0 120/240. generator. 5.0 BGA-3CR/16004C Serial # H800519383 A.C. VOLTS 120/240 I Think M1 and M4 are the two 120v and M2 and m3 are neutral not sure yet.
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  #23  
Old 02-23-2017, 02:30:51 PM
len k len k is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

One hint for finding shared neutral is a cable coming into circuit breaker panel , that is feed from 2 single wide breakers or 1 double wide breaker. It basically has the appearance of a 120/240 branch circuit.

Although there may be other configurations of shared neutral. IE if house is very old or a non-electrician did the work.
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  #24  
Old 02-23-2017, 09:57:58 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Quote:
Originally Posted by Steve Dawkins View Post
I believe your transfer switch has six switches that are three position, SPDT switches. It may also have six miniature circuit breakers that have pop out buttons for resets. If your switches are marked 1-6 (some manufacturers use letter designations instead of numbers) then you should have six red wires and six black wires that are marked 1-6. Switch #1 should have a red and black wire that are also marked "1". If this transfer switch is like all other manual transfer switches that I have installed, this is the way it should be wired:

1. Select a single pole circuit breaker in your house panel that you want that circuit to operate on generator. it can be a 15 or 20 amp breaker, but no larger than 20 amps.
2. Disconnect the wire from the load side of the breaker. Connect the load wire that you removed from the breaker to the black #1 wire from the transfer switch. After making the connection, hold the wirenut in one hand, and tug on the black stranded wire with your other hand to make sure you have a good joint. Solid and stranded wire connections can be tricky.
3. Connect the red #1 wire to the circuit breaker. After connecting it, tug on the red wire to make sure it is securely connected to the lug on the breaker. The transfer switch wires are stranded, and house wiring is solid. Stranded wire works better with some manufacturers circuit breakers than it does with others. Square D and Cutler Hammer type CH breakers hold stranded wire very well, because they have a clamping type washer on the set screw. That washer holds the stranded wire securely. Other manufacturers such as Siemens, GE and others have a set screw that bites directly on the wire. They work well with solid wire, but don't clamp very well on stranded.
Repeat steps 1-3 for the remaining five switches.
4. Connect the white neutral and green ground wires to your panel.

FYI, the red and black wires that connect to the twist-lock inlet plug don't correlate to the red and black wires that are numbered 1-6. The red & black from the inlet plug are for incoming power from the generator. They connect to the mini breakers in the transfer switch, which in turn connect to the GENERATOR side of each switch. The red numbered wires that connect to the circuit breakers in your panel will be isolated from the other wiring inside the transfer switch. Those red wires bring utility power from the house circuit breakers to the UTILITY side of each transfer switch. Only the black numbered wires will connect to generator power. Hope this makes sense.

I don't know if you can post photos on this site yet, but pics of your transfer switch would be helpful. You may have something totally different from what I am envisioning.
Great info. ! I did some more stuff on the generator to house / main panel. The way it is setup is Onan green and white neutral to the neutral buss bar and the Black hot paired to two 20amp breakers and I put them in a breaker slot in my panel. I also have a "Onan" breaker inline to the onan neutral. And for extra caution I have a manual shut off to all power to the panel shutting the power flow to the panel. I'm using (6) six gauge wire for all of this setup. My panel is bonded neutral. The house is about 18 years old. If you get this message could you please input to this. It all works fine.

Great info. ! I did some more stuff on the generator to house / main panel. The way it is setup is Onan green and white neutral to the neutral buss bar and the Black hot paired to two 20amp breakers and I put them in a breaker slot in my panel. I also have a "Onan" breaker inline to the onan neutral. And for extra caution I have a manual shut off to all power to the panel shutting the power flow to the panel. I'm using (6) six gauge wire for all of this setup. My panel is bonded neutral. The house is about 18 years old. If you get this message could you please input to this. It all works fine.
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  #25  
Old 02-23-2017, 10:39:52 PM
Steve Dawkins Steve Dawkins is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

I guess you opted out of installing your transfer switch? It would have ensured isolation between utility and generator power, and is probably UL approved. What you have done will work electrically, but is unsafe on many levels and violates electrical codes. Anyone with knowledge of safe installation practices and building codes will not condone your installation.
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Old 02-24-2017, 12:44:03 AM
Carteret Carteret is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

True story. I was at the supply house one day when a customer walked in.
He wanted to buy a wiring device of some type. Started to ask questions about the connections for it. Counterman looked at him then reached under the counter and pulled a sleeve of matches out. Told the guy to take one. The guy asked why.
Was told better to burn it down now than when everyone is sleeping.
The guy turned red and walked out.
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Old 02-24-2017, 01:28:12 AM
Ray Lynch Ray Lynch is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

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Originally Posted by Steve Dawkins View Post
I guess you opted out of installing your transfer switch? It would have ensured isolation between utility and generator power, and is probably UL approved. What you have done will work electrically, but is unsafe on many levels and violates electrical codes. Anyone with knowledge of safe installation practices and building codes will not condone your installation.
Amen.
Hopefully the op will re-consider the advice given in this thread and opt for the transfer switch.
Ray
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Old 02-24-2017, 02:09:47 AM
Steve Dawkins Steve Dawkins is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Years ago, we had a hurricane come through this area and knocked out power in some neighborhoods up to 11 days. I had a guy come in my office and beg me to make him a backfeed cord that he could hook his generator up to the dryer outlet. I told him that I understood his desperation and was sorry that I could not help him for safety and liability reasons. I felt for the guy, but was not willing to put my electrical license and our company in jeopardy. If something went wrong, I could imagine myself standing in court and his lawyer saying "Well, you're the expert. You should have known better. My client is just a homeowner and didn't know how dangerous this could be."

Over the years, people have told me they wouldn't spend the money to do it correctly because ONLY they would operate their backfeed system, and THEY knew how to do it safely. I've been to houses where that was done, and that person had moved on, gotten divorced, died, etc. and the house was sold. The ex-wife or new owners didn't know what to do with the installation. I would make a recommendation on how to make it safe. Sometimes they would have us correct it, and sometimes I never saw them again.

Last edited by Steve Dawkins; 02-24-2017 at 02:21:58 AM.
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Old 02-24-2017, 12:58:48 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

I would much rather use the transfer switch to do this correctly. My set up is totally disconected now. My transfer switch is a four (4) wire setup twistlock. I have looked all over to get the proper Diagram on my Onan Genset BGA 120/240V generator. I can not seem to find anything Diagram wise that makes me comfortable in changing my Onan wires for the two 120v leads to get the transfer switch connected properly. The transfer switch wiring itself is easy, black to appliance red to breaker etc. The transfer switch I have is a TK65000 20amp max in and 15amps. out 6 breakers with resets. My onan is set up as we speak for 120v. I heard since I don't have the onan power diagram that M1 and M4 are my two 120v leads. I have to have the four wires to do the connection. Your and other post have been noted for a re-connect the safer legal way can you assist on this matter? What ever you can do.\

I understand, exsisting wires removed and back to the Transfer switch setup.
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  #30  
Old 02-24-2017, 01:32:05 PM
len k len k is offline
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Default Re: onan 3 wire to 4 wire transfer switch receptical

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Originally Posted by echolake1 View Post
.... Onan Mod. # 5.0BGA 3CR/16004C...
...I can not seem to find anything Diagram wise that makes me comfortable in changing my Onan wires....
Your spec # is C ( it's a version #)


Manual numbers and link to them

900-0337 Onan BF BFA BGA NH RV Gen Service manual (01-1983).pdf <--------read this one
965-0227 Onan BGAL (spec C) Genset Parts manual (01-1983).pdf
965-0121 Onan BGA RV Genset Operator's manual (10-1977).pdf

http://www.twinslan.net/~n0nas/manuals/onan/

In service manual Look on page paper page 48 for reconnection diagram of the M1, M2, M3, M4 leads. It shows how you reconnect the M leads for 120 only or 120/240

Also note that the some of these leads are grounded to frame by the brushes. That is a Ground/neutral (G/N) bond. Code says system can only have one active G/N bond at a time. I'm guessing your transfer switch has a G/N bond too.

Last edited by len k; 02-24-2017 at 01:52:24 PM.
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Old 02-24-2017, 01:43:29 PM
Ray Lynch Ray Lynch is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Quote:
Originally Posted by echolake1 View Post
You are very right, You described mine accurately and your install instructions are right on the money. Now I have to get two 120v hots off of my Onan genset 5.0 120/240. generator. 5.0 BGA-3CR/16004C Serial # H800519383 A.C. VOLTS 120/240 I Think M1 and M4 are the two 120v and M2 and m3 are neutral not sure yet.
Take a meter and check M1 thru M4 to verify leads and voltage. Suggest you re - read Steve 's post #19. If M1 thru M4 check out you should be good to go for your transfer switch.
Download the manuals from the site Len posted.
Ray
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Old 02-24-2017, 01:56:43 PM
len k len k is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Before you reconnect the M leads would be a good idea to remove the band covering the brushes and make sure the grounded M leads are as per the reconnection diagram.
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Old 02-24-2017, 02:31:36 PM
Steve Dawkins Steve Dawkins is offline
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Default Re: onan 3 wire to 4 wire transfer switch receptical

Quote:
Originally Posted by len k View Post
Your spec # is C ( it's a version #)

That is a Ground/neutral (G/N) bond. Code says system can only have one active G/N bond at a time. I'm guessing your transfer switch has a G/N bond too.
Len, I doubt that his xfer switch has the N/G bond. The neutral wire probably runs straight from the neutral of the twist lock inlet plug through the xfer switch and greenfield for connection to the panel. If his switch has a built in receptacle to monitor utility power, the neutral would obviously connect to it also.

Multiple N/G bonds don't meet code, but I have a lot less heartburn with that than i do a backfeed system, unless there is a proper interlock. I have seen many older standby generators (particularly 12 lead units) that had a threaded stud welded to the stator for the neutral connection. No N/G isolation there.
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Old 02-25-2017, 02:37:13 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

I did for the time opt out on the transfer switch but after reading response answers I am back to the transfer switch but for right now, I'm on hold until I get the info. I need...

M1 and M4 Are each at 120v per my voltage meter Yes...
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Old 02-25-2017, 06:44:31 PM
Steve Dawkins Steve Dawkins is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Where was the other meter probe when you were measuring M1 and M4? Was it on the frame of the generator or M2 and M3?

Did you measure between M1 and M4? If so, did you get 240 volts?
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Old 02-27-2017, 01:35:36 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

Ground, on the Onan chassis. I will have to measure those two points you asked to be sure.
I get 120v on each leg, M1 120v M4 120v but across the two I will have to re- check. I thought I got ( 0 ) between the m1 and m4. that's why I'll have to test it again.
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Old 03-01-2017, 12:19:57 AM
turtmaster turtmaster is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

what amperage sizes are breakers on the side of the generator, if it is a 20a, and a 30, breaker i would replace them with 2, 20a breakers.
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  #38  
Old 03-03-2017, 11:50:04 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

They are both 20amp. and as far as I believe the the onan generators wires were never moved from there original positions or altered.
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Old 03-04-2017, 09:27:02 PM
echolake1 echolake1 is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

The meter I tested with showed that M1 OR M4 with the ground led ON Neutral showed 120v each as did the generators ground screw. with that being said, can M1 and M4 be used for my solo grounds??
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Old 03-04-2017, 10:14:15 PM
Vanman Vanman is offline
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Default Re: Onan 3 wire to 4 wire Transfer Switch Recepticle

What voltage do you read between M1 to M4?
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