enblethen
Moses Lake, WA
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It is a open neutral. Reason getting 230+ volts is that the system is putting some device in series through another device.
It is betwwen the power panel and the male end of your cord.
I would start by shutting power off to rig.
Open your AC distribution panel, Look in the back for the neutral buss. Disconnect each neutral, clean connection points, apply some electrical grease to the wire and reconnect.
Locate the transfer switch and inspect the neutral connections and if equipped inspect the neutral contatcs on the relay.
Inspect you male cord body for any signs of melting of plastic and look at the pins for dark spots. Cord body can be replaced easily.
If you have a cord real, you can try to fix but the slip rings can be hard to service. May need a new cord real or replace with twist lock style connector and remove reel.
Check connections in cord reel terminal box.
Bud
USAF Retired
Suzuki XL7 pushing Pace Arrow
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Chris Bryant
DeLand, Florida, USA
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Joined: 03/26/2003
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I would bet it's the reel, I would also wonder if the rig had been plugged in to a service that was miswired, and 2 in phase 50 amp legs, overloading the neutral.
But- it's really more likely that the neutral in the original transfer switch was loose, and the reel brushes and slip rings are bad.
-- Chris Bryant
My RV Service Blog
The RV.net Blog
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Salvo
California
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Good explanation. Thanks.
So the 230V is not a hard 230. As soon as current flows the voltage should drop quite a bit.
The OP should have a 3-led ac tester plugged into one of his receptacles. That would have indicated the error the first time it happened. Even though I haven't used shore power for over 4 years, I still got one plugged in my MH.
enblethen wrote:It is a open neutral. Reason getting 230+ volts is that the system is putting some device in series through another device.
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MPD56
Canada
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Salvo: Sorry I’m at slow typing, but will post anyway. If the neutral conductor opened, for example the brush in the OP’s power reel is sticking and not making contact with the slip ring. This would connect the loads that are connected to L1 and L2 in the panel in a series circuit. In a split phase system, this is one of the reasons why the neutral is there.
The input resistance of a meter is many times higher then any of the loads at the time he is measuring so the meter is reading all most the total 240 system voltage as if he measured across the two incoming phase wires. If a voltage meter didn’t have a high input resistance it might act as a short and trip the over current protection (Breaker). If you connected two 120 volt, 100 watt light bulbs in series and then connected them across 240 volts, you wouldn’t need or notice a missing neutral, it is when there is different 120 volt loads connected to each phase that you would need a neutral because simply Ohm’s Law says that largest load in a series circuit has the largest voltage drop across it. Also when the OP was measuring voltage at the receptacle the loads that he was connecting in series, the same current that was going through the meter was going was also going through the loads and if the voltage meter didn’t have a high enough input resistance the loads in series could have anywhere from almost 0 volts to almost 240 volts.
You bring up another good point about a 3 light plug in tester; if it wasn’t rated for 240 volts it could cause an unsafe condition.
* This post was
edited 02/24/12 04:39pm by MPD56 *
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MEXICOWANDERER
las peñas, michoacan, mexico
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Loss of neutral in a 3-wire 240 vac system will melt even the most expensive surge protector in the world. Do whatever it takes to stop loss of neutral. Sometimes I run a separate 6 gauge white wire as a neutral. Connect it to the neutral buss in your rig, and run it directly to your terminal post junction point where you hook up.
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sdagro
Independence,LA
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trailerbikecamper wrote:I ran into this a few years ago as an electrician in an office setting. The request for service call came in as: the computer keep shutting itself off and the lights are making a weird buzzing noise. After a few miutes of troubleshooting I found the probelm to be a loose neutral jumper in the panel. The jumper connected a neutral bar on each side of the panel to one neutral conductor.
FYI: When I tested the receptacle the computer was plugged into I was getting anywhere from 175-190V on a 120V plug in. My best advice is to check your neutrals, especially at your input from the power cord and inverter. My bet would be either that or possibly the cord itself. They are simply an injection mold, that relies on the cured mold to keep all the connecting parts in place.
You may want to remove the cord and test it for continuity too. I have seen more than one cord fal in my career.
Just got word from technician. Power cord checked out good. He said he twisted and turned and had continuity throughout the process.
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sdagro
Independence,LA
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Could new transfer switch be the culprit even though it is not fried--looks as good now as when new? Do not have generator. Probably should take it out completely, wire direct and hide transfer switch for future use. Also sounds like I should put in a twist lock 50amp receptacle and do away with the power reel. More bells and whistles add to more trouble. Steve
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sdagro
Independence,LA
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Could new transfer switch be the culprit even though it is not fried--looks as good now as when new? Do not have generator. Probably should take it out completely, wire direct and hide transfer switch for future use. Also sounds like I should put in a twist lock 50amp receptacle and do away with the power reel. More bells and whistles add to more trouble. Steve
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MPD56
Canada
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It might help the members help you if they knew the make and model of your transfer switch and power reel.
A transfer switch may indeed look as good as new but needs to be checked to verify that it is working electrically. There are ways to troubleshoot and verify if it is working correctly and rule it out completely.
The same with the power reel; it only takes the neutral brush to be a hair off the slip rings to cause your problem. But I would suspect to see burning on the neutral slip ring?
I’m not a big fan of changing parts to troubleshoot. I’m sure a good Electrician should be able to find the cause and repair or replace it to make your equipment reliable. There are testers that monitor and record events such as a circuit wire opening intermittently safely and without further damage to equipment.
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sdagro
Independence,LA
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MPD56 wrote:It might help the members help you if they knew the make and model of your transfer switch and power reel.
A transfer switch may indeed look as good as new but needs to be checked to verify that it is working electrically. There are ways to troubleshoot and verify if it is working correctly and rule it out completely.
The same with the power reel; it only takes the neutral brush to be a hair off the slip rings to cause your problem. But I would suspect to see burning on the neutral slip ring?
I’m not a big fan of changing parts to troubleshoot. I’m sure a good Electrician should be able to find the cause and repair or replace it to make your equipment reliable. There are testers that monitor and record events such as a circuit wire opening intermittently safely and without further damage to equipment.
Not sure of the model# of transfer switch but is is from Progressive Dynamics. Camper not here so do not know the Model # from reel. Saw one in Camping World website that looks just like it. Didn't think they had many different ones out there. Model# of converter is PD9260C,from Progressive as well. May let dealer put everything back in it and bring it home. Seems I know as much as they do. Will omit the transfer switch and do away with the reel as well.
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