New here
I have a Honda EM5000SX number on frame is EA7-1161074 great generator until last week Monday when I needed it. I fired it up and it has a auto throttle on off setting and it was on usually when it fires up it right away senses that it doesn’t need to run full throttle and idles down right away. But this time it kept on running at full throttle and noticed that it wasn’t putting out any voltage… I checked the fuses, breakers anything else I could think off but nothing helped. I measured with my meter and it put out 2 volts at the 120 setting and about 5 at the 240 outlet.
I started looking on the internet and asking at my work what to do next. They suggested to flash the field windings with a regular D battery. I thought oh well can’t hurt so I figured out where the wires are and flashed them at full throttle, kinda nerve wrecking putting 2 wires in there with the engine running pretty fast lol but to my amazement it started to put out power and sure enough it slowed down to its idle like it should.
After measuring the voltage my joy went to hell because now it was putting out at the 120 outlet 157 Volts at 55Hz and over 300 at the 240 outlet… Slowing the engine down to 120 Volts it runs at 45Hz revving it up to 60Hz it runs at 170volts Now there are a few things that can go bad on these gens but it’s very pricey to find out what it really is? Buying a voltage regulator and come to figure out its a diode?
So my question is with this information can anyone suggest what is bad?

 

You can disconnect and test any accessable individual componants but without a complete circuit diagram and some design specs you probably will not be able to draw many conclusions re overall performance.

That said it sounds as though the field regulator and or power control, if it has one, have failed. If it was a winding or brush issue you wouldnt be getting any output and the voltage following RPM suggests an AVR (Automatic voltage Regulator) problem.

I have had some experiance with a cheep genny, not a honda, that I couldnt get parts for, I ended up making an AVR with a great deal of help from the folks here.

Please post all the info you can find, it will allow constructive suggestions to be made RE testing.

Al

 

You can disconnect and test any accessable descrete componants but you will need far mor info to assess the performance of an AVR module.
I take it that its not an inverter based model.

Post any info you can find it will help getting qualified answers.
I ended up building a replacement AVR for a cheep genny, not honda, with a great deal of help from the folks here.
Al

 

Try this for manual with circuits, it does have a seperate AVR. http://wwe.poweredgenerators.com/honda/manuals/31Z21600.pdf doesnt seem to work all i did was google honda EM5000SX & found the manual with circ on page 50.

 

I could find a few but some are really crappy copies of old manuals turned into a PDF file this one is pretty good and I saw the AVR but the AVR regulates the voltage but the frequency is off too? does the AVR also regulate the HZ?
http://www.hondapowerequipment.com/pdf/manuals/31ZC2612.pdf

 

Try this for manual with circuits, it does have a seperate AVR. http://wwe.poweredgenerators.com/honda/manuals/31Z21600.pdf doesnt seem to work all i did was google honda EM5000SX & found the manual with circ on page 50.

Uhm.. ur link says, Oops! Google Chrome could not find wwe.poweredgenerators.com

 

http://www.poweredgenerators.com/honda/manuals/31Z21600.pdf

 

http://www.poweredgenerators.com/honda/manuals/31Z21600.pdf

Thanks for the link however this is the newer model and mine is made between 1993 and 2001

 

On these generators Frequency is RPM sensitive. For 60HZ should be 3600RPM when runing with a load. Canyou post good pics of the AVR unit? If voltage is incorect at these RPM then the fault will be the AVR unit.

 

If yours is wired as in your attachment then the AVR is simply that, a voltage controller, that works by controlling the field (FW). It senses the AC output (MW) and draws its power for the field from a seperate stator winding (EXW).
The tap used to sense the main winding varies dependant on the output switch, this means the AVR is always seeing the same reference voltage.

The freequency is entirly dependant on the RPM. 3000 if its 2 pole 1500 if ita a 4 pole

The RPM seems to be controlled by a throttle biasing device which is controlled by an auto throttle unit.
The DC system is supplyed from a seperate winding in the alternator marked (DCW).

I think you can be fairly sure that the AVR is toast because the throttle is responding all be it to a very high AC output that is probably confusing the auto throtle control.

If you have a bench supply with a current limit try supplying the field from it, with the grenny on a light resistive load, a bulb would be good.

NB. Just the PSU to the brush caps nothing else, disconnect the AVR completly.

(My little 2.2Kw unit only neaded 20v or so well under an amp to lighyt acouple of 60W lamps ... testing before I built the new avr)

If everything else is OK speed choke DC system then you kno the AVR is dead and had failed short.

Al

 

anyone find a replacement avr for honda ems4500

 

Hi and thanks all of you,
I bit the bullet and bought a new AVR for this generator, should be here next week or so and hopefully its the right one and brings this generator back to producing the right voltage.
I'll let you guys know