Hard-Wired EMS Location

[Camper_bob]

I think I'm finally going to get around to installing an EMS.

I think I've decided to install a hard-wired unit.

My question is whether there is any restriction on where in the line to wire it?

It would be super convenient to wire it in under my bed with all the other electronics, but that happens to be a LONG way from where the shore power cable enters the rig.

I know distances matter in some 12V applications, so I'm wondering if there is any reason the EMS should be wired in a specific place. Or if it doesn't matter where it is in the line run?

In my case, I'm thinking I'll install it in the shore power line just ahead of the transfer switch. That would make the wire run INTO the EMS about 15-20 ft or so from the shore power compartment. And the wire run OUT of the EMS a few inches into the transfer switch.

[RetiredOne]

Why not just get a portable, and plug it into the pedestal? If it malfunctions, you can quickly pull it out and plug in without it.

Not so easy with a hardwired unit...

[Grumpy]

Originally Posted by RetiredOne

Why not just get a portable, and plug it into the pedestal? If it malfunctions, you can quickly pull it out and plug in without it.

X-2 And if you trade rigs you still have it...

[pward]

My Hughes is located in the shore power line cubby and plugs directly into the shore power line. I would speak with tech support for whichever unit you decide to install as they are the definitive expert on installation. I would say your planned run is too long, but more important you would not have ready access to the unit. Mine shows status information, that I can also view via bluetooth on my phone, but I want quick access to the unit.

[pward]

Originally Posted by RetiredOne

Not so easy with a hardwired unit...

I installed plugs on mine so, one: the shore power line is detachable and storeable in a larger cuddy, two: I can bypass the unit very quickly, but would not have a reason to.

[Marcm157]

My progressive Industries is under my bottom bunk in the cord storage box. I did the Marineco Detachable cord at the same time so I had all that space available. Hardest part was working in the confined space under the bunk.

[RetiredOne]

I have a portable, and what I do when setting up is to plug it in by itself, and turn on the breaker in the pedestal, and see what the voltage is and if there are any errors, BEFORE I plug in the rig. Then, if everything checks out, I turn off the breaker and plug in the rig, and flip the breaker back on.

With a hardwired unit, hidden in a compartment, it would be a lot tougher to determine a bad pedestal... not something I want to deal with when setting up. Also, when walking around outside the rig, I can take a quick glance at the EMS to see what voltage and amperage levels are during the day, and if there are any error codes..

If, by chance, my EMS takes a dump, I also carry a standard surge suppressor as a backup.

[Camper_bob]

You all make EXCELLENT points about a detachable unit! I may end up going that way. I already have a good setup for something like that in my shore power compartment, so that would work pretty well.

Only disadvantage to this would be that I couldn't monitor the readouts from INSIDE the rig. Unless perhaps it had some blue-tooth connectivity? I'm going to have to see if this is a feature I can get on a non-hard-wired unit?

As for monitoring the unit if I were to hard-wire it, it has a remote "screen" that I can use to monitor status. My plan was to mount the remote screen right near the breaker panel at the foot of the bed if I were going to install the unit in there near the transfer switch.

[RetiredOne]

Originally Posted by Camper_bob

Only disadvantage to this would be that I couldn't monitor the readouts from INSIDE the rig.

What exactly do you want to monitor?

For me, the voltage is the most important. So, I just bought a plug-in voltage gauge from Amazon, that I plugged into the outlet on the side of my sink cabinet. I also installed a DC voltmeter in the side of the cabinet, so I can quickly glance at the coach battery voltages.

This way, a quick glance when I'm coming in and out, tells me both the AC and DC voltages.

When I'm wandering around outside, I'll glance at the EMS to see what the amperage draw is. Depending where the pedestal is, in relation to my windows, I can see the readings from inside the rig.

[Vicr]

Originally Posted by Camper_bob

I think I'm finally going to get around to installing an EMS.

I think I've decided to install a hard-wired unit.

My question is whether there is any restriction on where in the line to wire it? No.

It would be super convenient to wire it in under my bed with all the other electronics, but that happens to be a LONG way from where the shore power cable enters the rig. I installed mine under my bed and you don't have to worry about voltage drop with AC vrs. DC.

I know distances matter in some 12V applications, so I'm wondering if there is any reason the EMS should be wired in a specific place. Or if it doesn't matter where it is in the line run? The electrons don't care where you mount it or where the line is run.

In my case, I'm thinking I'll install it in the shore power line just ahead of the transfer switch. That would make the wire run INTO the EMS about 15-20 ft or so from the shore power compartment. And the wire run OUT of the EMS a few inches into the transfer switch.

Most EMS manufacturers offer a remote display that so you can monitor Amps and Volts on each incoming leg. I hardwired mine because I didn't like the fact that many campground receptacles have a lot of wear and I'd rather have a cord end ruined than the plug on the EMS and of course the theft factor. It's your RV do what you want. I can post photo's of my installation if you'd like, you just have to wait for me to get done with work.

[Marcm157]

Originally Posted by Vicr

Most EMS manufacturers offer a remote display that so you can monitor Amps and Volts on each incoming leg. I hardwired mine because I didn't like the fact that many campground receptacles have a lot of wear and I'd rather have a cord end ruined than the plug on the EMS and of course the theft factor. It's your RV do what you want. I can post photo's of my installation if you'd like, you just have to wait for me to get done with work.

Exactly why I hard wired mine...

[Camper_bob]

Originally Posted by Vicr

Most EMS manufacturers offer a remote display that so you can monitor Amps and Volts on each incoming leg. I hardwired mine because I didn't like the fact that many campground receptacles have a lot of wear and I'd rather have a cord end ruined than the plug on the EMS and of course the theft factor. It's your RV do what you want. I can post photo's of my installation if you'd like, you just have to wait for me to get done with work.

Excellent, thanks for the info!! I kind of figured it didn't really matter where in the line I install it.

That monitor panel is what I was talking about. The EMS I've looked at and considered purchasing come with one of those and a length of phone cable. Then you can mount your monitor panel wherever you can run the cable. In my case it would be a couple feet to the outside of the bed platform so I could monitor the status without having to lift up the bed. (as an aside, I wonder if you could use a common splitter so that you could attach a second monitor. Like for example, one on the bed platform, and another in the utility bay? Then I could see it from the inside OR the outside...

I'm not worried about the worn pedestal plugs if I go with a portable unit. The way my shore power is set up is a short "pigtail" at the RV that I plug into a longer cable that goes to the pedestal. So I would just plug the EMS inline between the pigtail and the cable. I would be able to lock the EMS in that little compartment then so as not to worry about theft.

As far as moving the unit to another RV when I decide to "trade up", it's HIGHLY unlikely I'll be moving into another 30A unit when we sell this one and buy another. I'll most likely move into a Super C with 50A service. That being said, I fully intend to install this so that it can be undone easily. So in the unlikely event we DO move into another 30A unit, I'll just take it out and take it with me.

So the last disadvantage of a hardwired unit is that if I ever have a failure, it will be a bit more difficult to bypass it. Not insurmountable by any stretch, but decidedly more inconvenient.

Thank you everyone! This is all really helpful as I make this decision!

[Route 66 Traveler]

Originally Posted by Camper_bob

So the last disadvantage of a hardwired unit is that if I ever have a failure, it will be a bit more difficult to bypass it.

Plus if it fails it will make a lot of stinky smoke inside your RV. I prefer the versatility of my portable Progressive EMS-PT50X. Simple to check the pedestal BEFORE plugging in the RV.