NH6800 Generator

[sternman99]

Hi, I Just obtained a NH6800 generator, there no other numbers I can find on this unit but a sticker saying that it was made by Honda for Northern hydraulics . It seems the auto throttle will not sense the load when activated. With the auto throttle turn off the generator puts out high voltage at operating RPM in excess of 300 volts plus across two polls and about 150 on single poll mode . Operating RPM is running at 3620 via dig tach, I'm assuming this problem is coming from the voltage regulator and or rectifier? I'm in need of some type of parts PDF .If anyone has any info on this unit or a direction I can go in to obtain parts or idea to remedy, please let me know. Any information would be greatly appreciated.

Thanks

[madmantrapper]

Post a few pics if you can. Also check the frequency, RPM may be high. Also some genset will produce a higher voltage with out a load on it.

[smallen]

northern hydraulics is now northern tool & equipment, check with their tech support for an ipl, this gen is powered by honda, maynot be honda generator head, open rear cover look for avr or capacitor, brushes

[sternman99]

Thank you for the responses. I will contact them and see what I can get from them.

[Arkie]

Use a Hz meter (frequency meter) instead of a tach. Adjust the Hz for 60-63hz. If Hz is too high the voltage will be high.
Without a load the lo voltage should be 125-135volts. Their usually is a large Phillips head screw up under the gas tank around the carb area and a large spring associated with the governor arm and carb linkage for setting the gen speed or Hz. Put a witness mark on the screw head and count number of turns you have to make to bring Hz down. (witness mark is for doing a reset to original setting if necessary later) If you do not have a electrical Hz meter you might try adjusting the rpm down too lower the voltage to 135 area and see how she acts. Then use your tach as a reset to 3620 if needed later. Normally for 130 volts on a 60 hz gen the rpm's are around 3750, but HZ (cycles per second) is what you really need to check. Sometimes you can find a HZ meter on ebay reasonable, but do not connect a wimpy electronic Hz meter to a Higher voltage than it's rated for or it may zap.

The auto throttle is a sensing solenoid connected to the carb throttle and pulls the carb throttle when senses load current of approx. 1-2 amps or more. check for any linkage binding mechanically first. Then try a resistance load for example a electric heater of about 1500 watts or so to test the auto throttle. (150 volts and surging will usually burn out light bulbs)
If you can find out what model Honda it's close too let us know. I have some Honda service data for several of their gens with troubleshooting tips on a CD. Northern tools will probably only have owners manuals, not SERVICE manuals.
Honda voltage reg's very rarely produce a high voltage, they usually operate correctly or no to low voltage. High voltage is usually too high a rpm.
Also NEW Honda voltage reg's are usually expensive, like $300 plus, and are sealed electronic module item and no warranty or return refund once purchased. I've bought good used Honda reg's from ebay for around $30-50 with careful shopping AFTER obtaining the correct part number. I've also seen the module reg become intermittent, no voltage then correct voltage erratically.
You might also try asking at this site for Gen issues. Look under the Honda section for posting. It's a gen electrical issue site and several old technical foggies hang out.
http://www.smokstak.com/forum/forumdisplay.php?f=6

[KE4AVB]

Gentlemen,

This thread (topic) is over 10 months old and we haven't heard anything from the original OP about needing any more help or if he got it repaired. His last visit was May 26, 2014.

As for the use of RPM vs HZ and Arkie can correct me if needed on a direct drive alternator using rpm can be more accurate in my thinking. Here why rpm divided by 60 (converts minutes to seconds) = Frequency (Hertz) so 3620 / 60 = 60.33+. This assumes a two pole alternator if it is a four pole version that is often use on diesels then you divide by 30.

[bgsengine]

As for the use of RPM vs HZ and Arkie can correct me if needed on a direct drive alternator using rpm can be more accurate in my thinking. Here why rpm divided by 60 (converts minutes to seconds) = Frequency (Hertz) so 3620 / 60 = 60.33+. This assumes a two pole alternator if it is a four pole version that is often use on diesels then you divide by 30.

unless you're working with a diesel generator or 2 phase or 3 phase or some other variation.. and BTW Briggs recommends a top no load of 3750 on most of their (formerly generac) Generators which would achieve approx 62Hz - It really depends on the manufacturer, but using Hertz meter to set engine RPM, you CANNOT go wrong - Indeed, if you were to find it necessary, in theory you could go and set a US built genset to 50Hz for U.K. Use - *in theory* - Ive never yet heard of it being done in practice though.

Ive actually found one generator only putting out 33Hz .. despite the outlet measuring 120V @3750 RPM ... until something gets plugged in the other outlet to create a load... then ya got 2V. - First one I'd ever seen do that, (But I'm sure, generator specialists see that all the time) Noticed the Hz output after plugging in the kill-a-watt, which led me to think only half of the generator output was being rectified.. quick run of continuity/resistance tests and replaced the rectifier/brush set and all was fixed.

[KE4AVB]

I was just thinking of single phase systems.

I just learning about repairing a two phase motor that receives single phase AC input. Simple system just haven't work on one before. Still awaiting on that run capacitor which I thought was a start capacitor; just hoping that the winding are not partially shorted from the high current. They using the run capacitor to provide a 90 degree voltage phase shift on one set of windings.

[Arkie]

I did not notice how old the original post was!
[b]BUT, why was it close to the top of the forum post list????????????????[/b]

Should have been several pages later??????????