Trying the Hugh’s Autoformer...

[3_tons]

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

Sent from my iPad

[3_tons]

Well the topic as to ‘what degree of surge protection’ is always debatable (though, not the primary topic of this thread), and quite naturally different vendors will provide various strategies or levels of ‘protection’ though I don’t see surge protection as the primary function of the autoformer. But to clarify, here’s what the user guide says:
(Also note that the previous Hughes model did not provide this feature)

“Surge and Spike Protection
The autoformer is designed to boost voltage. However, there is a built-in mechanism that will protect your coach from various spikes and surges. In certain instances, a surge or spike might actually damage your autoformer while it’s protecting your RV. In this case, your autoformer will likely need to be returned for repair”...

It goes on to say, “Your unit may have absorbed an electrical surge or spike. The autoformer is designed to absorb the damage while saving other appliances. If this occurs, return it to us for service”...

Either way, Per my aforementioned, admittedly unorthodox objective and use of the autoformer, it seems to be working out like a charm!

3 tons

[time2roll]

Honda voltage does sag as it approaches overload and I expect this exacerbates the starting issue. Correcting voltage should help.

[pianotuna]

Mr Wizard,

Well said and spot on as far as the Hughes unit.

Sola Basic does "buck" but would not protect from 240 volts as it only does 10%

[MrWizard]

An autoformer
Does NOT offer surge (sudden high voltage) protection
It DOES give some "voltage lag" protection
Where voltage drops under heavy startup loads
This is what the op is seeing, the autoformer boost/surges the voltage,
So there is less voltage drop/lag

That is NOT surge protection
That is low voltage protection

[pianotuna]

Seeing as the generator in question can put out only 120 volts, protection from a "open neutral" (the source of 240 volts) is not needed.

This thread is not about surge suppression but, here are my thoughts.

My own opinion is that the PI and SG are better only at the top of the line. My own feeling is they sell assembled parts and mark up the cost 1000%. They do use mov's as well.

Anyone who plugs in without checking voltage under load is taking a risk. Top of the line PI and SG do not check voltage under load.

I do have surge thanks to mexicowanderer, and that surge I'm told, is far better than PI or SG offer.

[Lynnmor]

wa8yxm wrote:


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.

Are you sure? The latest models have improved surge protection and replaceable parts.

[wa8yxm]

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.

[MrWizard]

we had 80*F here today

but it was only 60+ a few days ago

in the 50s at night

[pianotuna]

Better to post the results here--there is no particular rush LOL (below freezing here right now)

[3_tons]

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

[pianotuna]

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]

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

[pianotuna]

Nice to find yet another use for an autoformer!