Honda Generator Automatic Voltage Regulator

thatoneguy

Joined Feb 19, 2009
6,359
The Honda AVR is patent number 4535281 (1983), it includes a schematic different than shown above, and appears to utilize PWM rather than the linear operation of the field transistor.
 

thatoneguy

Joined Feb 19, 2009
6,359
If you have that model generator, they could be combined, with enough searching, an AVR is most likely available somewhere on the internet. The number of people looking for and owning them is pretty big.

Calling Honda with your serial number may get you some info on a part, if they no longer make it, beyond that, it would be a process like page 1.
 

nagaloo

Joined Jan 27, 2009
29
Sorry I have been away from this for so long. Parts come in this week hopefully. Let you know if it works or what blows up by next week hopefully.
 

nagaloo

Joined Jan 27, 2009
29
Well I finally got my parts soldered in. Even replaced a few just incase, well they were not reading quite like the new ones. Still no go. If I flash it while running with 24 vdc it puts out and comes up to proper output. But fades to 0vac as soon as the 24 vdc is removed. Hope to investigate more this weekend. Any ideas?
 

nagaloo

Joined Jan 27, 2009
29
Last board I got from my "small engine repair friend" was burnt different then the other 2 I had. His customer managed to get a new board but he had to install the new one before I had a chance to see what they had changed. He said the only difference he could "see" was the 2 heavy diodes and the resistor near them had been changed.
 

feathersg

Joined May 29, 2009
3
I bought a used bluemax JD8000 knockoff honda. It is reading 160+ VAC @ 120+HZ (120 VAC base), Was 300+ VAC (240 VAC base , now 0 VAC) and 35 VDC under no load conditions. I purchased it too fix it and was at the same conclusion that the AVR is fried and can no longer regulate the voltage. I can buy a new AVR from the manufacturer for $29.99, but now after reading these posts I am curious as to how to properly ventilate as the new unit will probably suffer the same fate.
 

steelm

Joined Jul 26, 2009
1
I have a Honda EM1800 generator with a bad AVR as well. I have pried the electronics out of the case and removed the Epoxy or resin (whatever it is) and managed to get to the components and the board. As far as components go, there isn't anything real magic there, but the layout would have to be followed to understand what is going on. I can take pictures, measure values and try to identify as best as I can if anyone wants to try and figure it out.
 

guaitiao

Joined Oct 13, 2009
1
Hi;

I have a Honda EX3300S Electric Generator that the Engine is running perfectly at idle mode, but no power is generated, neither the 12Vdc nor the 120/220VAC. I suspect that it is the Automatic Voltage Regulator, this is a half moon electronic part located at the end of the stator next to the raw voltage stator connections. It is about $200, but I need to make sure. This Generator is about 19 years OLD but it is like new. I had some problems with some small mice getting in and making some nests and damages to the fiber panels. No cable damages are shown...

Does anyone have the Service or Repair Manual for this Generator? Or Have any idea of what is going on? I check voltages at the service outlets, but none is coming out. Even the green light is off. However, the Engine starting by its electric starter and still running, I guess under the battery power to keep the engine firing. I need to measure voltage at each terminal and remove the battery after the engine is running. If Engines stops I know that it is not even generating from the coil, but I doubt it since it is independent from the generator it self. This engine is a basic engine with some enhancements to ensure automatic trottle depending on the power consumption. I am not sure what to expect from the raw voltages coming from the generator stator. Any Idea?

I appreciate any help in finding the repair, service and/or troubleshooting manuals!

After this I found a way to fix it...

Well this was back on time and I fixed....Just to let you know that I found that the residual magnetic field has been discharged after the generator was about a year of been off and no maintenance at all. YNUI YLI If you do not used you loose it!

I had the idea to regenerate the residual magnetism using the same principle to magnetize a screw river, making a quick direct current pass trough a cable coiled around the screw driver. After analyzing this the only thing I needed is a 12VDC High Current battery (Car), two jumpers, make sure I do not burn the brushes in the rotor and finally eliminate the possibility to get shocked by the same generator. So if I touch the brush terminal very quickly, ensuring polarity +/-, it must be polarized and charged. In order to do this I could disconnect the spark plug to avoid the engine to start automatically. Sounds wear but it could work.

However, after some search and reading I found a good trick, you can use a motor to generate the current you need to polarize the rotor coil and to generate the lost residual magnetism. So I used a 3/8" drill plugged into the generator outlet, and with the running engine, tried to spin the drill clockwise manually in forward, so it can use the same circuit to get to the rotor coil, creating some feedback current. So after several trails, I decided to increase the size of my motor, to a 1/2" drill. And did the same. After several trails, it worked. The Generator Coil was reactivated, generating the power and the drill started to run by it self. You just need a small amount of current, just enough to generate small amount of residual magnetism.

I talked to a friend to let him know since He had the same Gen problem. So he took the generator to a dealer and they charge him about $200, since �they changed the AVR�....I am sure he had the same problem� a discharged coil...since he described to me the same symptoms. SO this time I saved about $150 to $250....

I had the same problem now! after been running ok for about one year....But the Drill is not working to fix the problem.....The Problem Started when I was using the Gen to Power a Welding machine...Suddenly the Gen Stop to generate power...Has the same symptoms that before but re-charging the coils apparently is not an option...I suspect now the AVR is the one bad....Since it was generating power...or running with load when the power lost happened...

The Gen Motor runs perfectly...So...How can I ensure is the AVR without buying an expensive one...I will try to use my friends AVR...To replace mine and see if it works!

NO voltage at all in any of the connectors....I looked at the coil and notices a green colored wired as if the coil has burned in some portions?. Clean Brushes and rotor...but nothing! Now I am following your posts and I will keep track to see if someone can tell us the Honda EX3300s AVR component list....
 

lkenny

Joined Nov 3, 2009
1
This is an AVR from a Honda EG5000X, part # 32350-ZB4-632.
I have removed the epoxy from the circuit side using a heat gun.
I am currently removing the epoxy from the component side.

Removed Epoxy from component side.
Large capacitor has been de-soldered(470uF).
Now to draw the schematic!
 

Attachments

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feathersg

Joined May 29, 2009
3
I fixed mine for $30.00. I have a bluemax and I couldn't get any reply from the company for parts. Therfore, since everything is made in China and sold to import companies to market under various names, I checked with Champion which has parts lists for numerous gensets. I talked with a customer service tech (very helpful and located in the US - sell at TSC and Sears) and told him my KW size and he shipped the one I needed. Plugged right in and gave the proper voltage. I used it all summer to run a watering pump for my trees. For $30 it isn't worth trying to fix the old one.
 
I wonder if anyone got the avr to work yet? I just obtained a honda ems4500 that had a bad avr, unfortunately the avr didn't come with it so i can't dig into the components.
 

PZUFIC

Joined Jan 7, 2012
54
Hy guys. I come from Slovenia and I first read this topic about 6 months ago, when my original AVR on my 2600W generator broke down. I was looking for scheme for this regulator because my epoxy removing process was unsuccessful.

This circuit works fine but only in simulator. I build it and put it on my generator but when you put on and off the burden the induced voltage destroys all of three transistors. Also the diodes must be change with bridge rectifier because on nowadays generators there is just two wires coming out from the AVR power winding. I do a lot of tests of different circuits and destroy many components. Then I, with help from our Slovenian electronics forum found a solution. There must be the blocking high speed diodes behind every greatz and diodes on every BE junction. I hope that helps.

I just want to say thank you for the scheme witch was the basic for my design.:rolleyes:
 

tinkerman

Joined Jul 22, 2012
151
Here I am with a similar problem. I pulled the AVR and find the output transistor BU931T shorted. A Google search turns out it's a Darlington transistor, 10 A which probably controls the current to the rotating field. Anyway the gen puts out a constant 135+ volts so whatever the stator winding is putting out goes directly to the field without regulation. In similar circuits on the daylight running control of a Buick I was able to replace the output transistor with good success. A replacement BU931T is on order, (about $2.50 item). Hopefully this will fix the AVR. I will update in due course. I'm guessing the other internal components are not damaged. In both the DRL control and this AVR the heat sinks are inadequate.

Here are the components on the board:
R1 Dale CPF2 10k 1% TI 0504 I asume this is a 10k
R2 30k 5%
R3 56k 5%
R4 Rd Yel Wh Br Br Could be the reverse Small low watt
R5 Rd Rd Br Br Br Could be the reverse Small low watt
R6 pot 202 23 with a w no bottoms
R7 not used
D5 Glass no #’s
D6 MCC 3 1N4006
D7 MCC 3 1N4006
D11 MCC 3 60S10
D9 MCC 3 60S10
DB2 MCC DB104 Small bridge rect
C1 2.2uf 250v
C2 Had this on it 100B with a bar over 10 and 103 with 2 dots under 10
C3 470uf 200v
Q1 MPS A06 502
Q2 2N6 515 510
Q3 BU931T CC04L W MRC 449 This had over heated
S1 S2 S3 All the same CNR 10D391K These may be varisitors


I didnt get to test any of this stuff yet. I will need to find part #'s to match if these are not "normal" #'s
R4 & 5 I dont know how to decode these ?

I cant get the "attachments" to work for uploading my files? Any help there?
 
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