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10/20/2019 1:36:51 PM EDT
Hi guys. I was sent to this board since you guys know quite a bit about generators and off-grid equipment.

I was gifted a used generator by my brother in law, a Powermate 5k watt that's about ten to twelve years old. It seems nice for what it is. It has a 10hp Briggs engine with a Gererac generator. It had been sitting up in his car port for a while. It was dirty, but it had been put up well. I got it running after replacing a few parts, like the rotted fuel hose. It now runs well for the most part.

I tested the voltage with a digital multi meter the other day. With no load, it's putting out about 128 volts. I don't know if that's normal or not. I have read that as you add high amp items, the voltage will come down to normal levels, so it's not a problem that it's higher with no load.

It has a four-prong outlet for 240V, but that outlet is also putting out about 128 volts. I don't see a switch or lever to change the outlet over to 240 from 120. Or does it auto-sense based on load? I don't have much experience with generators. I have one of my own, but it does not have a 240 outlet. The 240 outlet indicates that it can also output 120V as well, presumably for camper use that would require it to output 120V. So, I wasn't sure how that worked if you want to use the outlet for 240V.

Lastly, I was looking at replacing the pull cord on the starter. Typically, there are screws or bolts that hold the "re-winder" portion of the assembly to the engine. However, on this one, it looks like it's held in place by rivets. I thought maybe it was hex head screws, but on close examination, the holes in the fittings are round. That doesn't make any sense, because to replace the pull cord rope, you have to be able to remove that piece. If it's riveted in place, how would you be able to remove it to replace the cord? I'm a bit puzzled by that.

Anyone have an ideas? Thanks!
10/20/2019 2:58:06 PM EDT
[#1]
Didn't you post this question already?
10/20/2019 3:09:50 PM EDT
[#2]
128 volts is normal under a no load condition. Put a load on it and it will drop.
10/20/2019 3:29:32 PM EDT
[#3]
the recoil starter on Briggs and Stratton used (operational word used) to be accessed by removing the entire engine shroud... 3 cap screws....the recoil spring itself was threaded into the unit, wound, and then a new rope was installed... it has been a lot of years since I worked on one though...
10/20/2019 3:59:07 PM EDT
[#4]
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Quoted:
Didn't you post this question already?
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I was told to post here since there is more generator discussion on this board than on the other board I posted on.

But, yeah.
10/20/2019 4:04:36 PM EDT
[#5]
Quote History
Quoted:
the recoil starter on Briggs and Stratton used (operational word used) to be accessed by removing the entire engine shroud... 3 cap screws....the recoil spring itself was threaded into the unit, wound, and then a new rope was installed... it has been a lot of years since I worked on one though...
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It does look like the shroud comes off somehow, although it doesn't look very easy. Despite being a decade or so old, the rope doesn't look bad. But, I was looking to replace it now rather than having to do it once the lights go out. I was hoping it was a bit easier than that, but it is what it is.
10/20/2019 6:31:07 PM EDT
[#6]
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Quoted:
Didn't you post this question already?
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I recommended that he post it over here.    He posted it in the [General]-> [Zombie Central] but it wasn't getting much traction there.

OP:   Did you recheck the 240 voltage across the different legs?

2Hut8
10/20/2019 6:54:32 PM EDT
[#7]
Quote History
Quoted:

I recommended that he post it over here.    He posted it in the [General]-> [Zombie Central] but it wasn't getting much traction there.

OP:   Did you recheck the 240 voltage across the different legs?

2Hut8
View Quote
How do I test across the different legs? The socket itself shows that it can do either 120 or 240V. My guess is that, at default, it outputs 120V for camper applications, but I don't know if you'd have to manually switch the socket to 240V or if it auto senses. There's no switch that I have seen, although I may be missing it.

The model is a Powermate PM0545007. I don't have a manual for it and I've not had much luck finding one online.
10/20/2019 8:16:25 PM EDT
[#8]
Quote History
Quoted:
How do I test across the different legs? The socket itself shows that it can do either 120 or 240V. My guess is that, at default, it outputs 120V for camper applications, but I don't know if you'd have to manually switch the socket to 240V or if it auto senses. There's no switch that I have seen, although I may be missing it.

The model is a Powermate PM0545007. I don't have a manual for it and I've not had much luck finding one online.
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Quote History
Quoted:
Quoted:

I recommended that he post it over here.    He posted it in the [General]-> [Zombie Central] but it wasn't getting much traction there.

OP:   Did you recheck the 240 voltage across the different legs?

2Hut8
How do I test across the different legs? The socket itself shows that it can do either 120 or 240V. My guess is that, at default, it outputs 120V for camper applications, but I don't know if you'd have to manually switch the socket to 240V or if it auto senses. There's no switch that I have seen, although I may be missing it.

The model is a Powermate PM0545007. I don't have a manual for it and I've not had much luck finding one online.
Depending on plug type a 240V will generally have 3-4 wires. Neutral, Line 1, Line 2, and ground.

N->G 0V
L1->N/G 120V
L2->N/G 120V
L1->L2 240V
10/20/2019 9:37:40 PM EDT
[#9]
Quote History
Quoted:

How do I test across the different legs? The socket itself shows that it can do either 120 or 240V. My guess is that, at default, it outputs 120V for camper applications, but I don't know if you'd have to manually switch the socket to 240V or if it auto senses. There's no switch that I have seen, although I may be missing it.

The model is a Powermate PM0545007. I don't have a manual for it and I've not had much luck finding one online.
View Quote
ASSUMING that you are using a multimeter and ASSUMING that this is your generator:

http://www.powermate.com/pdfs/2007/11/16/manual_pc0545007.pdf

Then the generator is equipped with two 120 volt duplex receptacles and one 240 volt, four wire receptacle.

The 240 volt connector should be an L14-20R.   If that is the case then one of the pins has a bend in it.   That pin is the ground.    Measure the voltage between the two pins that are adjacent to the ground.   I would expect to see approx 250 volts across those two pins.   If these instructions do not make sense then find a friend that understands electricity and ask them to assist you.

I hope that helps,

2Hut8
10/21/2019 6:49:39 AM EDT
[#10]
Quote History
Quoted:

ASSUMING that you are using a multimeter and ASSUMING that this is your generator:

http://www.powermate.com/pdfs/2007/11/16/manual_pc0545007.pdf

Then the generator is equipped with two 120 volt duplex receptacles and one 240 volt, four wire receptacle.

The 240 volt connector should be an L14-20R.   If that is the case then one of the pins has a bend in it.   That pin is the ground.    Measure the voltage between the two pins that are adjacent to the ground.   I would expect to see approx 250 volts across those two pins.   If these instructions do not make sense then find a friend that understands electricity and ask them to assist you.

I hope that helps,

2Hut8
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If the 240V outlet is capable of 120V as well, what controls whether or not the outlet outputs 120V or 240V? Does it depend on what's plugged in to the socket? It's not just a 240V socket.
10/21/2019 7:24:33 AM EDT
[#11]
Explanation of how to test your outlet.
10/21/2019 8:21:05 AM EDT
[#12]
Quote History
Quoted:

If the 240V outlet is capable of 120V as well, what controls whether or not the outlet outputs 120V or 240V? Does it depend on what's plugged in to the socket? It's not just a 240V socket.
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In the US, our 240V power consists of two individual 120V lines of AC electricity operating out of phase of each-other. When both hot legs are used the 2 voltages add up to 240V. So there is no "detecting", the power is already there on 2 different hot lines. Coupling a hot line to neutral will yield 120V, and coupling both hot lines together will yield 240V.
10/21/2019 5:59:47 PM EDT
[#13]
Quote History
Quoted:

If the 240V outlet is capable of 120V as well, what controls whether or not the outlet outputs 120V or 240V? Does it depend on what's plugged in to the socket? It's not just a 240V socket.
View Quote
Others have answered this but I am going to try to provide a different an overly simplified explanation.    Voltage it relative.    A 120 volt circuit means that the difference between the two wires  (Positive and the Neutral) is 120 Volts.    In this case, the 240 volt circuit is because when one wire reaches 120 volts, the other wiring is basically -120 volts so the difference is 240 volts.   Please note that this is an overly simplified example and technically incorrect but it explains the premise.

Yes, you can take 120 volts off the 240 volt outlet and use just 120 volts as long as you provide a neutral.   That is what is going on inside most residential distribution panels.   If you connect to power on one side then it is a 120 volt circuit but if you connect to BOTH (oppositie) sides then it is a 240 volt circuit.

I hope that helps.

2Hut8
10/21/2019 11:47:29 PM EDT
[#14]
I little long, but this video will help you understand 120/240 split phase

[youtube]fJeRabV5hNU?t=176[/youtube]

That 4-prong outlet (typically a L14-30) will output 120v and 240v at this same time depending on which contacts you are testing.  There are two 120V "legs".  Measured Leg-neutral, you get 120V RMS.  When you measure leg-leg, you get 240V.  The reason is that the two legs are out of phase from each other.  Simply put, at a given point in time one is +120V and the other is -120V.  The total difference is 240V.
10/22/2019 6:03:44 AM EDT
[#15]
Ah, okay. I understand now. It depends on what legs the plug is designed to use. So, a clothes dryer will use the full 240V, whereas something else will only use 120V. That makes sense. I've never used a generator that could output 240V before, so I wasn't sure how it worked.

Knock on wood, it's been a few years since we've had a hurricane pass through here that was strong enough to knock out power for any real length of time, maybe Issac in 2012. But, every year, it's always a possibility we'll get a bad one and lose power for a week.

Thanks for the info. I suspect my brother in law used the 240V socket wired to his breaker box after Gustav in '08. That one was a monster for my area.
10/22/2019 12:31:24 PM EDT
[#16]
Quote History
Quoted:
Ah, okay. I understand now. It depends on what legs the plug is designed to use. So, a clothes dryer will use the full 240V, whereas something else will only use 120V. That makes sense. I've never used a generator that could output 240V before, so I wasn't sure how it worked.

Knock on wood, it's been a few years since we've had a hurricane pass through here that was strong enough to knock out power for any real length of time, maybe Issac in 2012. But, every year, it's always a possibility we'll get a bad one and lose power for a week.

Thanks for the info. I suspect my brother in law used the 240V socket wired to his breaker box after Gustav in '08. That one was a monster for my area.
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Also, the two windings in many generator heads are wired 'in series' [as most Home Depot gennys are in this context] for 'split phase' 120/120/240, similar to house wiring from the transformer.

Or the genny head windings can be wired in parallel to double output current at 120vac, if a source of 240 is not needed.

Our 6000 watt light tower head is factory wired for both 240 and two 120 legs, and if our big 120vac air compressor is connected to a 120 leg there isn't enough current at 120vac to start it.

So to solve this and not rewire the head [quite easy though] and still have 240 available from it, I found an Outback auto transformer on eBay and use it to transform the genny's 240vac down to 120vac at twice the current of one 120vac genny leg, and start the compressor.

This sort of transformer can be made from large transformers or Variacs.
10/22/2019 12:33:12 PM EDT
[#17]
dup

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