Need help with a portable generator

[Kernopelli]

I have a Briggs and Stratton Storm Responder 5500/8250, model # 30430 (030430). It has four 120V receptacales and one 240v outlet. It is producing 190+ volts on the 2 upper 120V receptacles and >10V on the two lower receptacles. The 240 outlet has 190V+ on one side and >10V on the other. I assumed the Voltage regulator was shot so I looked up the parts diagram and it doesn't list an AVVR so I opened up the alternator and can not find an AVR! I have since talking to B&S customer service ( who told me their diagram doesnt show an AVR so it doesnt have one and only dealers can talk to their techs). I then called a local trusted dealer's tech and he cant find any reference to a regulator in any of his material for this model. I went ahead and changed out the brush holder/rectifier ( the ONLY electrical component inside the alternator) and still experience the high/low voltage issue.

Another issue that has me scratching my head is there are two120V outlets w/ two receptacles each just like a standard home outlet and are they mounted vertically i.e. it would stand to reason I should get high voltage on 1 upper and 1 lower receptacle and low voltage on the other side's upper/lower receptacles!???!

My dealer just called me back and said he was able to talk to a B&S tech who was at first surprised there was no AVR on this model and then went on to say that the rectifier
must also act as a regulator( is that possible?) . Then the tech went on to tell him is is likely a bad rotor. Anyone have any ideas on what I should do next?

 

[CobyRupert]

Are you running loads directly off (plugged into) the generator (like hand saws, lights, etc...) or are you plugging generator into your (grounded/bonded) house system.
Do the two voltages add up to about 240V (or 220V)?

What I'm getting at, like mentioned above, is your generator may be producing 240V just fine, it just can't split it evenly into 120V (on 2 legs) because the neutral is not grounded to zero volts (i.e. earth). If you are NOT plugging it into your grounded house system, (that locks "neutral" to zero volts, thus splitting 240V evenly in each leg to 120V) check that the neutral lug on generator is bonded to the genny's ground (the frame).

 

[LouNY]

There was a posting just the other day of a generators wiring schematic,
the two 120V receptacle have the jumper broken off which connects the
hot side of the upper and lower receptacle, I believe the neutral jumper
may have been removed also.
As CobyRupert asked are you getting 220-240Volt when measuring the 240 outlet?
The bonded neutral and gound may have come loose.

 

[Kernopelli]

It would be nice to see a copy of the electrical diagram. I would open it up and check every single wire connection. The symptom sounds like the common open or floating ground in 120/240 house wiring. In your case, it might be some kind of center tap problem.

Here is a link to the parts manual. Wiring diagram is on page 16. What do you mean by "center tap? I will also check every wire connection.

Are you running loads directly off (plugged into) the generator (like hand saws, lights, etc...) or are you plugging generator into your (grounded/bonded) house system.
Do the two voltages add up to about 240V (or 220V)?

What I'm getting at, like mentioned above, is your generator may be producing 240V just fine, it just can't split it evenly into 120V (on 2 legs) because the neutral is not grounded to zero volts (i.e. earth). If you are NOT plugging it into your grounded house system, (that locks "neutral" to zero volts, thus splitting 240V evenly in each leg to 120V) check that the neutral lug on generator is bonded to the genny's ground (the frame).

The two voltages add up to +/- 200V. I just checked the receptacles again and got 191.3V on the two top ones. 1.5V on the two bottom ones. 240 outlet showed 191.1V on one side and 1.6 on the other side.

I have plugged a 2.5HP/ 14amp compressor into a high voltage side 120V receptacle for approx. 30 secs. Voltage on that receptacle stayed at 191v under load. The compressor wouldn't run on a low voltage receptacle. I also plugged 120v from the generator into an outlet on my patio, it would throw the house's 20 amp breaker on that circuit. I also turned off main breaker in house and plugged the generators 240v into our clothes dryer outlet. It powered several 110 circuits in the house but quickly fried the power strip my computer and printer was plugged into.

I will check the neutral and ground wires.

There was a posting just the other day of a generators wiring schematic,
the two 120V receptacle have the jumper broken off which connects the
hot side of the upper and lower receptacle, I believe the neutral jumper
may have been removed also.
As CobyRupert asked are you getting 220-240Volt when measuring the 240 outlet?
The bonded neutral and ground may have come loose.

Thanks. I am going to dive into the wiring tomorrow!

 

[mini14]

it might use a capacitor for voltage regulation, look to see if there is one and check to see if it is bad