Forum Discussion
briansue
Dec 23, 2016Explorer
To use the ISB for a standard US wired RV with so called "50 amp" you would need two ISB units. 50 amp actually gives you a total capacity of 100 amps.
"50 amp" is two legs of hot and the ISB is only built for one leg.
The 4000 unit comes out to be good for around 40 amps and the 8000 unit is good for around 80 amps. But these rating would only be for one leg so you would need two units for two legs.
A normal "dogbone" adapter for plugging a 50 amp plug into a 30 amp outlet splits the one leg of 30 amps so you have power on each leg of your 50 amp system - but you still only have a total of 30 amp capacity.
I think two of the 4000 would be enough for the normal US RV as that would give you two legs of 40 amp instead of two 50 amp legs.
Most Mexico travelers will not be finding two leg plug-ins in Mexico. We have to learn to do with less.
What is unique about the ISB unit that is not found on other brands found in the US is it will BOTH raise low voltage and lower high voltage - and you can only find them in Mexico.
The 4000 runs around $200 US and the 8000 runs around $250 US I think. I once saw one on eBay or something like that in the US and they wanted about $2,000 for it - don't know if they ever sold it or if it was a misprint.
"50 amp" is two legs of hot and the ISB is only built for one leg.
The 4000 unit comes out to be good for around 40 amps and the 8000 unit is good for around 80 amps. But these rating would only be for one leg so you would need two units for two legs.
A normal "dogbone" adapter for plugging a 50 amp plug into a 30 amp outlet splits the one leg of 30 amps so you have power on each leg of your 50 amp system - but you still only have a total of 30 amp capacity.
I think two of the 4000 would be enough for the normal US RV as that would give you two legs of 40 amp instead of two 50 amp legs.
Most Mexico travelers will not be finding two leg plug-ins in Mexico. We have to learn to do with less.
What is unique about the ISB unit that is not found on other brands found in the US is it will BOTH raise low voltage and lower high voltage - and you can only find them in Mexico.
The 4000 runs around $200 US and the 8000 runs around $250 US I think. I once saw one on eBay or something like that in the US and they wanted about $2,000 for it - don't know if they ever sold it or if it was a misprint.
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