Hi all,Ambient temperature 73 FShore power 30 amp with no other person providing a load. No load voltage 117.2 volts.Loads: Dometic Fridge, and Magnum inverter charger. No charging being done at the moment.The Air Conditioner is equipped with a microaire unit. No autoformer:328 watts 117.2 v (fridge on 120 volt setting)1367 watts 109 v recovering to 110.2With Sola Basic autoformer327 watts 117.2 volts1426 watts 114 volts recovers to:1501 watts 121.2 voltsAfter running for 20 minutes:1750 watts 120.2 volts.There is a difference in the sound of the air conditioner when I listen outside the RV.I have tweaked the Sola Basic to do first boost at around 113 volts.

Damage to motor windings can begin when operating on 108V or lowerI prefer AC Voltage above 110V under load

I say it a different way.I.E. above 107 volts.

Hi Don, So am I correct to assume that the wattage gradually increased by almost 400w due solely to the extended run time?...I get similar results with my air cond...

Hi 3 tons,Yes, and wattage will increase more as ambient temperatures rise. I've measured up to 1900 watts on a hot day after a couple of hours of constant run time.

Don,Very interesting numbers which show constant amps (12.4A) with changing voltage for the refer and A/C. If the refer is the absorption type then it uses less amps with decreasing voltage and hence the A/C uses more.It would be interesting to see the numbers for the A/C only, all other appliances off.

air conditioner without and with autoformer | Good Sam Community

jharrell
Explorer
Aug 01, 2019
Make sure Magnum shore setting amps correct, you should have noticed it, but Magnum could be trying to charge batteries and run a/c, lowering shore amps tells the charger to back off, also tells it when load support kicks in on hybrid.

Autoform and generator really not a good combo, if gen can't provide voltage auto form pulls more current, dragging gen down even more. Gen should be throttling up to provide correct voltage and current up to its capacity otherwise something wrong with it.
Cummins12V98
Explorer III
Aug 01, 2019
"The best bang for the Buck are autoformers from Mexico"

Are you talking a cheap knock off Made In Mexico? "AutoFormers" are top quality and Made in USA.
3_tons
Explorer III
Aug 01, 2019
Thats odd...assuming that your battery’s SOC was up to snuff, then even if in Eco, I can see no reason why the Magnum’s load assist feature would not readily kick in to facilitate this temporary deficit...(triggered by ‘i’ sag??)...

My ProSine is not a true hybrid, but will (in same scenario) momentarily bare the entire load (via ATS) which provides sufficient time (seconds) to overcome a LRA amps condition, and for genny to adjust to what’s now a ‘running amps’ load...This is why (in my previous...) I mentioned a reset of the Magnum to factory defaults as a possible solution...Just saying
pianotuna
Nomad III
Aug 01, 2019
Hi 3 tons,

I do have the microaire.

I was pretty surprized. Nothing was on except the Magnum which was drawing 50 watts.
3_tons
Explorer III
Jul 31, 2019
pianotuna wrote:
One last test--which had disappointing results.

Ambient temperature 76 f

Interior of RV 81 f

Yamaha 2800 sIEB run for 2 minutes to warm up. eco switch off.

No load voltage 122.1v

turn on only air conditioner

97 volts recovering to 119.5 1101 watts

Retest with eco switch on after waiting ten minutes.

generator over load

Retest with magnum load support turned on

generator over load

Retest with autoformer

generator overload.

Not what I was expecting at all.

Don, Something seems amiss here, especially if you have the Soft-Start....Converter-charger is off?...Autoformer operable?

Be advised that I had a similar problem, and was ultimately able to correct it by resetting my ProSine to it’s factory defaults...

Even when only Standby mode (not inverting) it may passively shut off shore power from entering the coach if the Genny voltage or Hz is sub-par...Sub-par voltage could be a parameter of the programming.
pianotuna
Nomad III
Jul 31, 2019
One last test--which had disappointing results.

Ambient temperature 76 f

Interior of RV 81 f

Yamaha 2800 sIEB run for 2 minutes to warm up. eco switch off.

No load voltage 122.1v

turn on only air conditioner

97 volts recovering to 119.5 1101 watts

Retest with eco switch on after waiting ten minutes.

generator over load

Retest with magnum load support turned on

generator over load

Retest with autoformer

generator overload.

Not what I was expecting at all.
Planning
Explorer
Jul 31, 2019
MEXICOWANDERER wrote:
Costco down here has triplite voltage correction 2000 watt capacity for around sixty dollars

Is that for a 50 amp 2 leg system?

I did discover that the Hughes has a hardwire accessory (almost turnkey) available.

https://youtu.be/UrlcSvUJGIs
Planning
Explorer
Jul 31, 2019
joebedford wrote:
Planning wrote:
I never go south of the 42nd parallel north
You must love winter.

Also nothing east of 96°, west of 118°, or north of 49°
joebedford
Nomad II
Jul 31, 2019
Planning wrote:
I never go south of the 42nd parallel north
You must love winter.
wa8yxm
Explorer III
Jul 31, 2019
NOte on Air Conditioners if the wattage cimbs after a few minutes of operation you may need to do rooftop A/C maintenance (Clean condenser coils)

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