Old Honda generator - high Hz question

[ripcord]

I was given an old Honda generator, a pre-inverter type. The model is EG1000 and I'm guessing it is from the 80s. I cleaned up the carb and got it running, and it will light a 250w work lamp nice and bright but I checked the frequency of the AC I see 190hz! I haven't put a tach on it, but the engine is not rev'ing up like crazy. 190 is not much more than 60 x 3 = 180, so I'm wondering if I might be seeing multiple phases? Bad rectifier it something? Any suggestions as to the issue?

This thing is old and loud and puts out less than 1kw so I am not willing to spend more than a pitance to fix it, BTW.

 

[nomas]

What is 60x3=180 ?

 

[nomas]

Engine RPM x number of poles divided by 120 = frequency . If your RPM's are good , you got something bad going on in the electronics .

 

[ripcord]

Household AC current in the USA normally runs at 60hz, but that's only a single phase of the current. Industrial AC can run three phase power. I don't pretend to understand how that works, though, and was throwing out a wild guess.

 

[ripcord]

Engine RPM x number of poles divided by 120 = frequency . If your RPM's are good , you got something bad going on in the electronics .

That's what I was thinking.

 

[skyactiv]

It'd be interesting to plug in an old synchronous electric clock and look at the second.

 

[eljefino]

Whatever you're checking cycles with is too sensitive, it's picking up blips that "shouldn't count." I'd aim for an indicated 180 hz. I like skyactiv's clock idea.

You could also put a timing light on it and check it with a movie camera (phone) running at 60 fps, if you have it close you'll get a "beat frequency" that'll go away when you nail the correct 3600 RPM.

 

[ripcord]

Whatever you're checking cycles with is too sensitive, it's picking up blips that "shouldn't count." I'd aim for an indicated 180 hz. I like skyactiv's clock idea.

You could also put a timing light on it and check it with a movie camera (phone) running at 60 fps, if you have it close you'll get a "beat frequency" that'll go away when you nail the correct 3600 RPM.

I was using my cheap auto sensing VOM to test the HZ, so I don't doubt what you're saying. I put an OPE tach on it just now and saw it was a hair over 3600, so I adjusted and now I've got it to 178hz. I tested it with a sacrificial corded drill and it ran at about same speed as when I plugged it into mains power.

Looking for something else to test it with that I don't care about...

 

[jhellwig]

Were you using an old halogen or incandescent light or is it an LED? Were you checking it while there was a load or running with no load? What kind of meter do you have? Generators can do funny things with modern electronics and when unloaded and cheap meters can be iffy. Could be regulator issues, filter capacitor issues or a number of things.

"Three Phase" is not 3 60hz signals running on top of each other. It is 3 lines of alternating potential that are 120 degrees off sync from each other. They do not add their frequencies.

 

[ripcord]

I was testing the frequency with no load.

My meter is an auto-ranging Amazon special with a DC amp clamp. Meterk brand. I get 59.9hz when I test against mains power.

 

[oil pan 4]

Put some incandescent work lights on it for a load and retest.

 

[eljefino]

Put some incandescent work lights on it for a load and retest.

Or a hair dryer on low heat, should be around 700 watts. The resistive load will absorb the "noise" like the incandescent bulbs, and usually the engine governor will be running a bit slower under heavier load. Read here that the ideal generator should be set for around 62 hz unloaded, to account for getting closer to 60 under load, which is probably where you started, LOL.

 

[ripcord]

Dang. Y'all were right.
<Insert copyrighted pic of Joe Dirt>

With a 100w incandescent light plugged in I see 60.2hz. I just wasted a bunch of Internet on this, I guess.

 

[oil pan 4]

Dang. Y'all were right.
<Insert copyrighted pic of Joe Dirt>

With a 100w incandescent light plugged in I see 60.2hz. I just wasted a bunch of Internet on this, I guess.

No you didn't. You leaned something and other people will see this and now they'll know it too.

Or a hair dryer on low heat, should be around 700 watts. The resistive load will absorb the "noise" like the incandescent bulbs, and usually the engine governor will be running a bit slower under heavier load. Read here that the ideal generator should be set for around 62 hz unloaded, to account for getting closer to 60 under load, which is probably where you started, LOL.

Yeah I set mine for 61, 62 sometimes 63hz depending on that generator and its load.