We installed the Progressive Industries EMS into our unit about a year ago. You can find the information about it here:
Now that we have used it for over 4 weeks and about 11,000 miles of continual use, these are some of our observations:
It works well.
When we arrive at a new park and I plug the trailer into the park power box, I always look at the EMS display to see if the power is appropriate. We have asked the park to move us to a different site if errors show on the display.
No matter what kind of park you are at, the voltage fluctuates. We were at a state park this past weekend, and the power varied from 105 volts to 115 volts.
During hot weather and weekend camping when the parks are full and air conditioning is on the power is most apt to have low volts.
In our trailer, we must have the water heater on gas, and the refrigerator on gas to be able to run the air conditioner and microwave at the same time.
I purchased an autoformer last year in Las Vegas because the voltage was so low at the park pole. The autoformer works well and the air conditioner sounds better with it on. Itís a bit pricey but it works.
With nothing else running in my trailer, the ac draws about 20 amps to start then settles down to 14 amps when its running.
My next project will be to install a xantrex battery monitor and intellipower with charge wizard to protect and charge my batteries appropriately.