I've been putting it off for a couple of years, but I finally broke down and purchased a Progressive Industries EMS (Electrical Management System), simply put "a surge protector".
The manufacture is Progressive Industries, and the model number is EMS-LCHW30. This is a hardwired in-line model with an integrated digital scrolling display, but there is another model that has a remote digital scrolling display (EMS-HW30C).
Some of the features of the EMS-LCHW30 are:
* Surge Protection
* High/Low Voltage Protection
* Polarity Protection
* A/C Compressor Time Delay
* Open Neutral/Open Ground Protection
* Display reads: Source Voltage, Amp Draw, Source Frequency, and Fault Codes
* The EMS box can be mounted horizontally or vertically, plus for viewing the digital display it has four plug-in positions to accommodate the EMS box mounting preference.
Manufacturer's Product Information: http://www.progressiveindustries.net/ems_lchw30.htm
I purchased my unit from: http://tweetys.com/electrical-manage...re-30-AMP.aspx
They have been a great source for RV accessories, and will price match (which they did on my EMS purchase).
Locating a place to install this particular unit will very depending on one's floor plan and 30amp wiring location. In my case the location I chose was ideal and provided a means for easy access and viewing of the display.
My water/cable/electrical connections are located at the street-side rear corner of my TT, and can be accessed inside the TT by sliding a panel out of the way:
What made the location ideal was that it also housed the junction box for the 30amp shore cable, so in theory all I had to do was replace the junction box with the EMS unit.
The installation instructions supplied were easy to follow, and considering I'm more comfortable with a 1/2" drive ratchet in my hand says a lot!
Mounting the EMS to the side of my 30amp power cord storage box provided a better view of the digital display, and kept it clear of the carpet in the event it got wet. I wasn't sure if the EMS box would get warm during operation, so I used some spacers with the four mounting screws thus creating a 1/4" air gap between the EMS box and the mounting surface. It's not seen in the photo, but I do have the 30amp shore cord clamped to the floor so it can't be accidentally pulled at/or around the EMS box.
The EMS unit has a built in time delay for the A/C compressor in the event of a source power or EMS interruption. The unit comes with two different time delays, 15 seconds and 136 seconds. The default is 15 seconds, and 136 seconds (use if existing A/C doesn't have it's own built in time delay) which can be enabled by removing the supplied circuit board jumper. I have yet to determine if my Coleman Mach A/C has it's own time delay...., and with the help of JOF member "Quahog" we hope to confirm this ASAP.
Once I plugged my shore power back up, the EMS unit takes a few seconds to check the source power, then the power is released to the TT electrical system.
One mod always seems to lead to another, so I'm considering installing a Marinco detachable power conversion kit http://tweetys.com/detachable-power-...sion-kits.aspx
. Another option would be to make my own by purchasing a male 30 amp plug and a female outlet. Cut off the RV cord coming from the EMS unit leaving 2 feet hanging outside the TT and attach the male plug at the end. Then attach the female plug onto the remaining 30 amp shore power cord.
It will be interesting to see what type of fault codes the EMS unit displays as I venture into different CG's.