How to install EMS

[JohnGaines]

I'm looking for some help or advice on how to install PI EMS-HW30C in my 2017 Sunseeker 3050S. Two things concern me. I only have a small amount of wire to work with in the storage compartment. The wires come into the storage compartment and go immediately to the power in plug. Will I be able to unhook those wires and hook them to the HW30C and then run Romax type wiring to the power in plug? How and where should I attach the HWC30 to the side wall?

[bob caldwell]

If there's a spot to attach it if you were to cut factory wire, you could just install where you cut the wire...
Might be enough slack...

[JohnGaines]

there's maybe only 6 or 8 inches of wire to work with. So was hoping to unwire it from the power in plug and hook that wire to the HWC30. Then run 10/3 household wire to the back of the power in plug? I'm not even sure if I can get access to the back of the power in plug to wire it or unwire it and I don't know where it is safe to put screws in the storage compartment.

[325BH]

Originally Posted by JohnGaines

there's maybe only 6 or 8 inches of wire to work with. So was hoping to unwire it from the power in plug and hook that wire to the HWC30. Then run 10/3 household wire to the back of the power in plug? I'm not even sure if I can get access to the back of the power in plug to wire it or unwire it and I don't know where it is safe to put screws in the storage compartment.

With that little amount of slack, you may want to install a junction box where you can splice in extra length of Romex. Once you do that, you can make the splice as long as you want which allows you to mount the EMS wherever you want.

The the electrical world, a junction box is just a 4"x4" box (usually around 2" deep that has knockouts in it for you to install wire connectors to protect the wire as it goes through the hole) with a cover. You just use wire-nuts to connect your length of Romex.

[JohnGaines]

that seems to be the way I will probably go. Do you know if I will have problems un-wiring and rewiring the power in plug? I haven't seen how the wires are connected there. I am hoping they are just screwed on?

[elind]

I bought a couple feet of wire and added it starting at the breaker box. By connecting the wire at the breaker box it gives it enough slack to connect the EMS. You may need a longer piece of wire if locating the EMS box needs more room somewhere else.

[325BH]

Not sure.

My camper is 50 amp, so the 50 amp wire inside the camper is Romex. It runs from the receptacle to the breaker box. (50 amp rigs use a separate cord that plugs in at both the pedestal and camper.)

If yours is 30 amp, I am assuming you have a 30 amp cord that you pull out and plug in to the pedestal, right? If so, that cord is stranded wire and I'm not sure how and where it first connects inside your rig.

I may not understand your "power in plug" description.

[Iwannacamp]

I assume you have a removable cord on RV. This then assumes there is romex from the connector to the existing converter. If there isn't enough slack to attach to that wire... then you must extend the wire. I recommend not splicing that wire, but to replace with longer wire and proceed with normal installation. New wire from EMS(or piece you took off) to converter... Most challenging part of the two I did were the space limitations of the cabinet. It is an easier install than one would think other than stiffness of wire, limitations of space and mounting the EMS. I recommend spacers under EMS for cooling.

[bob213]

I have seen where people add a pigtail on both ends(of the EMS) with twist lock plugs and receptacles(from existing wire) for easy connect and disconnect.

[itat]

Originally Posted by bob213

I have seen where people add a pigtail on both ends(of the EMS) with twist lock plugs and receptacles(from existing wire) for easy connect and disconnect.

I did this but found that the screws holding in the wires on the plugs would loosen over time so I took them out and wired directly.

I removed the main 30A line from the main breaker in the power center and connected that to the input side of the EMS, then ran new Romex from the output side of the EMS back to the main breaker in the power center.

My WFCO power center uses these plastic cable connectors. When you pull the cable out of the back of the power center you have to destroy these things so I replaced the one when I reconnected to the power center.

[Alleyantique]

I found it easier to replace the wire from the plug than to replace the wire to the breaker panel. It makes no difference which piece of wire you replace, just go for the easiest in your rig. The power connector has three screw connections for the three wires and easily separates from the vehicle. Remove the four screws and pull straight out. Replace the wire and reinstall. You can drive screws in any wall, just don't hit anything in the wall and make sure the screws won't go all the way through the outer skin. Sounds complicated but is really quite simple.

[JohnGaines]

That sounds like a great plan Alley, thanks.

[elind]

Originally Posted by Alleyantique

I found it easier to replace the wire from the plug than to replace the wire to the breaker panel. It makes no difference which piece of wire you replace, just go for the easiest in your rig. The power connector has three screw connections for the three wires and easily separates from the vehicle. Remove the four screws and pull straight out. Replace the wire and reinstall. You can drive screws in any wall, just don't hit anything in the wall and make sure the screws won't go all the way through the outer skin. Sounds complicated but is really quite simple.

It's just a matter where the EMS will fit in and how far the digital readout screen can be placed from it.

[W9HAM]

You might want to consider adding 30 amp power plugs in line with your installation. I had my unit go out and it was a pain to take it out of line and rewire the power connections. Now I can quickly remove the unit and plug in the power without rewiring should the unit go out again.

[RamblerGuy]

Originally Posted by W9HAM

You might want to consider adding 30 amp power plugs in line with your installation. I had my unit go out and it was a pain to take it out of line and rewire the power connections. Now I can quickly remove the unit and plug in the power without rewiring should the unit go out again.

Someone posted a year or so ago about doing just as W9HAM suggested above. I can't find the post at the moment. He used twist lock plugs.

Has the original poster considered leaving the 30 amp shore line in place and installing the EMS between the automatic transfer switch and the breaker panel? That's the way I did it. That way the EMS protects the coach from problems from both the shore power and the generator. I found that the EMS will drop out with overload before a breaker will trip. The EMS protects the generator better that the breakers. The EMS resets automatically so you don't have to check the breakers.

[325BH]

Originally Posted by bob213

I have seen where people add a pigtail on both ends(of the EMS) with twist lock plugs and receptacles(from existing wire) for easy connect and disconnect.

I did this with my hard-wired 50 amp... but I used regular male and female plugs. (I guess technically plug and receptacle.)

I liked how it turned out, but wrestling with that 6/3 is no fun!

[Steve-W]

I just recently installed the EMS in my 2017 3051. I ended up installing installing it under the fridge. I removed the romex feed from the power panel and there was plenty of slack to connect it to the EMS. I then used a 10 ga piece of romex to connect to the EMS to the power panel. I mounted the remote display above the power panel. I opted for this location for a few reasons. The contactor in the EMS will emit a slight hum when energized, having that right under the bed would be a major problem as I am very sensitive to 60 Hz hum (Spent my life in electronics field). Also getting the remote wire from that location to somewhere unobtrusive in the coach would be a fair amount of work. Keep in mind the constantly cycling display can be very distracting which is why I wanted it inside the coach but very low as to stay out of the line of sight sitting or standing. I mounted the EMS to the underside of the plywood that the fridge sits on, I isolated it with two strips of rubber cord to further reduce the hum and provide air space under the EMS box as it will get very warm from the contactor coil being energized.
This method places the EMS after the transfer switch, I personally do not see that as a issue. When connected to shore power the transfer switch is not energized and thus just passes the shore power though the contacts of the contactor in the transfer switch. The electronics in the transfer switch are only connected to the generator input side of the transfer switch.
As far as adding twist lock plugs for easy removal, that method adds 18 additional connection points to the primary AC circuit path. That just not something I personally feel is necessary.

[itat]

Originally Posted by RamblerGuy

Someone posted a year or so ago about doing just as W9HAM suggested above. I can't find the post at the moment. He used twist lock plugs.

These are the 30A plugs I originally used.



I had to remove them because the screws holding the wires kept loosening.

[Wolverine 1945]

I guess all this info is the reason I went with a plug in @ the pedestal,,, + cost !!!
I know probably no comparable !!!

[325BH]

Originally Posted by Wolverine 1945

I guess all this info is the reason I went with a plug in @ the pedestal,,, + cost !!!
I know probably no comparable !!!

The pedestal version is just as good. It protects the same way and has its digital display just like the hard wired one.

Installing the hard wired one can be a pain, but has its conveniences like being inside secure out of the weather.

I started with a pedestal version and eventually got a hard wired one. It took me a while to install it because I was under no pressure since I had the pedestal one.

I still bring the pedestal version with me and use it to check the pedestals for me and others before setting up. It is very nice to have.