Generator Frequency

[velvetfoot]

I used my handy-dandy Kill-A-Watt unit this evening with my 5kW generator that I was powering a 3 amp nameplate drill I was using to drill holes for planting bulbs a ways from the house. I never did see the locked current draw but I did notice that at no load the frequency was about 62.5 cycles per second. I think I set the speed to spec after I fixed it (I have an rpm gauge) but I don't remember what that was anymore. As I recall, when I used a couple of hair dryers the rpm dropped a little (not positive). Anyway, how sensitive are your average household consumers like big screen tv's, microwaves, and for some heat-related relevance, pellet stove electronics? (I realize that the ultimate would be a solid state voltage controlled generator (or whatever it is) but this is what I have).

Thanks.

 

[GVA]

Most electronics just need clean noise free power +or- say 5 volts from nameplate spec. If you adjusted the frequency down then the voltage will follow in a reletive way such as saying 120volts=60hz and 110volts =50 hz. Motors however are more suceptiple to voltage or frequency changes.
Just wondering are you saying that you set the generator based on the speed (nameplate) of the drill. If so this is not the most accurate way to do this.

 

[velvetfoot]

Thanks for replying. The whole drill thing was extraneous, except that I could hear the generator 'ramping up' when the drill stalled. I had been thinking about buying a new cordless drill to do this, and wasn't sure if even that would be up for it, so I wound up using a corded drill and a generator I hardly use to power it. It felt good actually using the generator for something useful. I bought an electronic rpm gauge and used it a while ago to set the speed. It was only recently I got the kill-a-what meter. I guess I could have used that to set the speed using the frequency reading, but if I recall, they want you to be a bit high because it sags with load, which I believe I remember seeing before with those 3000 watts of hair dryers. Maybe I'll try it loaded again and take some readings (hmmm... not sure if I have a suitable way to get the dryers into the one outlet in the Kill-A-Watt.

 

[GVA]

3000 watts of hairdryers is 25 amps of current thats alot on a 41 amp generator. most of that is the heater element though. Motors can act funny sometimes flc and lrc and free load current are all far apart from each other. Yesterday I replaced a 25 HP motor on our small compressor and full load rating is about 40 amps at 480 volts while I was checking the phases and amp readings the run current was about 25 amps, full load was about 32 amps, and startup (inrush current) was about 150 amps, It scares you when you see a amprobe crank that high sometimes.

 

[velvetfoot]

I was checking the load on the electric splitter with a 10 amp motor I bought the other day. I got it over 11 amps max when splitting and it went over 17 on startup. Maybe I was still thinking about that when I mentioned the drill - which I never got any readings on.