30 amp variac instead of an autoformer?
Hi, I've been looking for a 30 amp autoformer for some time. I wonder if this item would "fill the bill". 30 amp variac $169 Here is the company listing: variable ac transformer
Forum Discussion
Hi greenrv,
My inverter is capable of 23.3 amps (3000 watts continuous) @ 120 volts. I've seen it draw 242 amps @ 12 volts.
As far as wattage goes, I've seen the air conditioner drawing 1900. Add the fridge @ 325 and at 105 volts that's about 22 amps.
When I saw IOTA I thought of a converter--not a power supply.
I just looked at bestconverters and the IOTA goes up to 90 amps. Even two would only give me 190 of those 242 amps. Cost is 337 each plus the cost of a parallel kit @ $23.10. This is more than an autoformer.
Input voltage is listed as a disappointing 108 to 132 volts.
I only want to support the voltage when on shore power--particularly at campgrounds.
When I had the Cobra MSW inverter I often used double conversion, especially when there was only a 15 amp shore supply. However, I did not run the roof air on that inverter.
My inverter is capable of 23.3 amps (3000 watts continuous) @ 120 volts. I've seen it draw 242 amps @ 12 volts.
As far as wattage goes, I've seen the air conditioner drawing 1900. Add the fridge @ 325 and at 105 volts that's about 22 amps.
When I saw IOTA I thought of a converter--not a power supply.
I just looked at bestconverters and the IOTA goes up to 90 amps. Even two would only give me 190 of those 242 amps. Cost is 337 each plus the cost of a parallel kit @ $23.10. This is more than an autoformer.
Input voltage is listed as a disappointing 108 to 132 volts.
I only want to support the voltage when on shore power--particularly at campgrounds.
When I had the Cobra MSW inverter I often used double conversion, especially when there was only a 15 amp shore supply. However, I did not run the roof air on that inverter.
greenrvgreen wrote:
The reason I specified the Iota DLS is that it will provide continuous current at its rating virtually indefinitely. It is a POWER SUPPLY with (mediocre) multi-stage charging capabilities. Therefore it is perfect for this task.
With a $25 pendant you can link two similar DLS units and double your amperage. If you are on a 30A shore connection that is showing 90 volts (normally unusable), with line losses in the 30% range you will have perfect power from your inverter, perfectly protected. No autoformer or variac can do this.
If your inverter is capable of providing 30 amps, then at maximum draw your battery depletion rate would be ~8A (AC). Say you have a 300ah draw limit from you bank, that would be three hours.
But how often do we pull 22 amps? And how many people have an inverter capable of providing that? The realistic scenario is that your draw from inverter will never exceed your charge from the Iota, and you can continue for the entirety of your stay at the campground. I've done it and it works amazingly well!
Even better, you can add another, external charger powered by a gennie. During periods of heavy inverting, ANY charge voltage will contribute 100% of its amps to the battery.
