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3_tons's avatar
3_tons
Explorer III
Mar 31, 2019

Trying the Hugh’s Autoformer...

The problem I’ve looooong been trying to overcome is to be able to get the Coleman Mach 1-P.S. 11kbtu AC to run while the honda genny is operating in the ‘eco’ mode, but always without any luck...The genny runs it just fine when NOT in the eco mode - but at much higher RPM, higher noise levels and fuel greater consumption.

I also have a powerful pass-thru inverter-charger that (when desert dry camping) I often keep in the standby mode...I have tried to run the air with genny in the ‘eco mode’, but to no avail - each time I’ve attempted this the inverter picks-up the entire air conditioner load then tries unsuccessfully to hand the load back to the genny, but the genny (in eco) struggles and is never able to resolve this sudden increased load - so the inverter takes the entire air conditioner load and happily carries on until I switch the genny off of eco...

So I swapped out the OME start cap with a electronic wiz-bang soft start, but with still no luck at this scenario while in eco mode...Then thinking I may need more power, I traded up from the trusty Honda 2000 to a Honda 2200, yet still no dang luck (Ugg!)...

So yesterday I pulled the cover off the Coleman and did a Ohm winding test and a continuity test, but found all to be within Coleman specs, including the running amps...I had tried this last summer but got higher numbers, so this time I used two different meters and both meters validated what the other read...

Still looking for an elusive answer, about a week ago I decided to take the ‘sage advice’ of Pianotuna and pulled the trigger on Hughes 30a Autoformer (delivered to my door), and placed it between the genny and the camper...

BRAVO!! After several test trials, what actually happens now is that with the Honda running uber quietly at near idle in eco mode, when the AC compressor ‘kicks on’ (with the inverter in standby), the inverter kicks in momentarily (3-4 sec) to allow the paired autoformer-genny ‘duo’ a moment to recognize and overcome (slightly rev) this SUDDEN, higher amperage load, whereby the genny (while still in eco mode...) happily assumes the entire air conditioner load, with only the slightest increase in RPMs!!...Granted, ambient temps today were only at about 57degF, but it seems that FINALLY all is now well in the high Nevada desert! Many Thanks to Pianotuna!!

3 tons

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  • wa8yxm's avatar
    wa8yxm
    Explorer III
    3 tons wrote:
    FWIW I should note too that the Hughes Autoformer also doubles as a surge protector...
    As to my above scenario, it appears to act as a buffer between the load and the power source...JMO

    3 tons


    Yes and no on the surge protector comment.
    the hughes has MOV's (Spike suppressors) in it. these are what are sold as "Surge Suppressors" in many stores (The six outlet strip type) but are a long way from what I call a Surge Suppressor.

    A spike is a very short (like 1/120-1/60 second) long "Surge" in voltage. the MOV's absorb and clip that spike protecting you.

    But if you get a sustained surge (Example you plug into a 240 volt 30 amp outlet) ... well those MOV's sound like firecrackers when that happens and are no good at all.

    A Progressive Industries HW-50C will display 240 volts do not bypass. and protect you from your mistake.
  • we had 80*F here today

    but it was only 60+ a few days ago

    in the 50s at night
  • Better to post the results here--there is no particular rush LOL (below freezing here right now)
  • 3_tons's avatar
    3_tons
    Explorer III
    pianotuna wrote:
    Any chance of you using two meters to monitor the voltage before and after the autoformer?

    My generator is a bit larger at 2800 watts (Yamaha sIEB), and will start the roof air in eco mode--but voltage tumbles way way down (about 90 volts). I've successfully used the Magnum in load support to help with starting--but it does cause the red "fault" light to come on. I do have the microair added to the roof air.

    I'll have to try using the Sola Basic autoformer between the generator and the RV.


    Will be kinda busy tomorrow but I’ll see what I can do (readings may have to wait till Monday - I’ll PM you the results)....Sounds like our systems are very similar, so I’d bet you’d see a similar or same result by positioning the Sola Autoformer just after the Yamaha...

    3 tons
  • Any chance of you using two meters to monitor the voltage before and after the autoformer?

    My generator is a bit larger at 2800 watts (Yamaha sIEB), and will start the roof air in eco mode--but voltage tumbles way way down (about 90 volts). I've successfully used the Magnum in load support to help with starting--but it does cause the red "fault" light to come on. I do have the microair added to the roof air.

    I'll have to try using the Sola Basic autoformer between the generator and the RV.
  • 3_tons's avatar
    3_tons
    Explorer III
    FWIW I should note too that the Hughes Autoformer also doubles as a surge protector...
    As to my above scenario, it appears to act as a buffer between the load and the power source...JMO

    3 tons

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