Electrical Management System (EMS) Installed

BrianZ

Over these first 4 years (has it been that long already?), most of our T@B camping was in Virginia state parks where we never had any electrical issues (that I know of, but how would I know for some things like voltage issues?).  Now that we've camped at all 23 of them that allow RVs, and we are planning a trip using private campgrounds where we won't know what to expect, I've decided to get the EMS HW30C from Progressive Industries installed for extra protection.  Below are my photos.

It seemed rather simple what needed to be done, but this installation took me longer than expected due to the tight working space and having to wrestle that stiff 10G wire in small spaces.

Here's a view of the source cable from the AC plug routed through the Alde compartment and into the electrical compartment..

The fake scissors shows where I cut the cable, and my plan was to pull those ends through the wall for mounting the EMS box on the other side.

Below is where I would mount it in the electrical compartment..  (ignore the two sets of nuts & bolts in the wall - that is a U-bolt which holds in place my 3-way glycol service valve shown in the previous photo)

The cable half from the converter was easily pulled back through its hole in the wall.

For the other half of the cable, I drilled a 5/8" hole below the conduit near the outer wall, plus pilot holes for the screws to mount the box..

And a view of the other half of the rerouted cable from the plug..

Below shows how the cables are wired to the relay switch/contactor, and just the ground wire from the converter cable remaining to be bolted to the ground plate..

Note the black/hot wire from the converter goes through a hole in the donut shaped current sensor.  The smaller circuit board at bottom right in the box contains the surge unit, where you see two of the blue MOV components.

I added a thin piece of plastic foam sheet under the base of the box to dampen any potential sound it might make..

Some have reported a hum.

This just shows the cable from the plug going through the hole I drilled..

And an overall view of the finished mounting..

I installed the display unit near the floor between the outlet and the CO/propane detector, just to have it obscured at night, because of those darn red LED lights that flash continuously - all the time with no switch to turn it off.  If there is any one thing to complain about, that is it.  As others have said, it would still be visible by the door, but it's difficult to read from anywhere that you can't view it straight-on.  Why in the world didn't they make it an LCD display, or at least have a push button momentary display?  Here's what the display looks like..

Seems like a really stupid design, not to mention the energy that is wasted 99.9% of the time.

A better mounting solution for that display would be nice, and also a solution for easily bypassing the EMS  in the event of a blown surge unit - one that would not require removing the wiring to the box to bypass it, like maybe a simple bypass switch wired in next to the box.

Other than those issues, it is up & running

Also tested running the ac unit to see how it would respond on our 15A circuit that runs through both a 30A extension cord plus the regular T@B cable..

Before turning on the ac unit, the display showed 124V, 0A, E0 (I interpret the E0 code as "Everthing Ok".)

With ac on low power, it read 123V 3A E0, and after turning it up to high power, it read 122V, 4A, E0, so the system seemed to handle it just fine.  I didn't try adding more loads, but will at some point when on a 30A source.

UPDATE (6-18-21):
I found a new location for the flashing display that seems like the best option for usage, while hiding the annoying light..

There was just the right length of cable to place it in the upper kitchen cabinet where it's easy to read, yet hides the light.  I also added 2 layers of red automotive lens repair tape to dim it a bit.  I would have added more, but it starts to lose contrast with more than 2 layers.  I plan to put a piece of strong but removable gaffer's tape over the bypass switch on the display, to help prevent accidentally switching off protection when getting items from the cabinet.
I ran the silver display cable from the EMS unit through the black conduit to the front of the trailer using a stiff wire, and into the compartment behind the toilet..

I used some black gaffer's tape to attach the cable to the side of the wheel well to keep things tidy.  The tape is strong like duct tape, but is removeable without leaving adhesive stuck on things.
I cut the snake wire shorter, and from the front compartment behind the toilet, fed it up through the higher opening in the  wall to pull the silver cable through (camera is next to the water pump behind the toilet for this shot)..

.. and into the cabinet housing the Jensen entertainment unit (after removing it to pull the wire through).  It was difficult at first, until I found that I needed to feed the wire through the right side of that small opening.  I used duct tape to attach the silver cable and its telephone style connector to the snake wire.  I tried to wrap it tight to protect the plastic clip on the connector & keep thickness to a minimum.  It was a snug fit, but went through after I found the correct spot away from thed front wall.
There was already a small opening at the top corner of the second cabinet space to feed the cable through from the Jensen compartment.  Of course, I had all the power disconnected while doing the wiring. 
I was happy to see they provided just the right length of cable; so I'm on a roll, since my rooftop backup camera also came with just the right length to reach down into the electrical compartment.

manyman297

Great install. I just installed the Hughes Autoformer Power Watchdog in our 400 and it was also a really awkward space (behind the lower drawer under the wardrobe. Still have scrapes and bruises from trying to squeeze in and out of that space. 

I think having these EMS devices is totally worth the peace of mind. In fact it's already done its job as I was trying to run the AC off our generator using a too-long of an extension cord and it cut the power off because the voltage was too low.

tybladesmith

Hi @BrianZ, Nice install! 
The cover can be mounted right side up to make the error codes easier to read. Also did you get the HW30C model, the remote display has the bypass switch. 
• ByPass: This switch is located on the remote display and allows the user to bypass the EMS in the event of failure, thus allowing AC power into the RV. This does not disable the surge protection portion of the EMS; however, all other features are disabled.

rh5555

Good job!  Anyone copying this might consider replacing all the 10 AWG romex cable with a stranded alternative. It is easy enough to replace the wire at the bayonet connector and inside the converter.  Routing stranded wire is way, way easier.

BrianZ

Thanks, @tybladesmith, and yes, I was aware of the bypass switch for allowing a generator to work without a neutral connection, but I'm not sure if it would still allow current to pass through if the MOVs inside the surge unit have been blown.  If so, then no problem for temporarily inserting a backup plugin surge protector on the front end of the 30V cable at the power pedestal.
Also, I left the cover as is to correctly identify the cables, and I posted the little paper chart of error codes that comes with the device on the wall nearby for reference.

BrianZ

Great thought, @rh5555, about the stranded cable; however, I did not want to tackle additional new connections at the plug and inside the converter.

BrianZ

Below are just a couple of observations & followup on my installation, and I should mention that I have added some important updates & photos of my new display location to my original installation above..

First, I have to say that Progressive Industries' tech support is very responsive with answers to questions, and I get the impression, both from written & phone contacts, that techs have firsthand knowledge of their products.

As others have reported, the box emits a buzzing sound that's more like a hum in terms of volume.  How loud?  Here's what I measured from a few inches away..

Below 40db is labeled a "whisper", so it's not all that loud, and I doubt we will hear it underneath the bed, but that remains to be tested.
I also noted the box does give off a small amount of heat, not hot, but very slightly warm.  I thought I'd find power consumption listed in their literature specs, like any other electronic device, but nothing, so I sent an email to their tech support.  Here is how they addressed these 2 concerns:

"In my testing the EMS consumes ~ 100 mA to power the logic board and keep the contactor engaged.

The hum or buzzing is likely the contactor’s solenoid there is usually a slight 60 hertz hum from the unit when the solenoid is energized. If the contactor is not secured to the to the housing the hum could be louder as it may be vibrating between the case and the nuts that retain the contactor to the case."

Jason Schreiber

Technical Support Repesentive

I should mention that I also spoke with them by phone a couple days ago to try to get a better understanding about the issue of power surges, and whether, if there has been one and the unit reports an E10 error code indicating that the surge protector circuit needs to be serviced, would the unit continue to deliver power or would it shut down?  I also asked whether the bypass switch is of any use in this situation.  

The short answers were "probably" and "maybe", but it really depends on the situation and how much energy gets through to the circuits.  The bypass switch was only designed to handle bypassing the protection circuits other than surge protection, and in most cases of power surges it should continue to deliver power.  However, if a surge with enough power damaged the other logic circuits, that might shut the system down, and it's possible that the bypass switch could allow it continue delivering power in that situation if the surge circuit was not totally damaged.  He had seen systems with both situations, but for most E10 surge codes, it continues to deliver power, and use of the bypass switch is irrelevant.

I explained that I was considering keeping our old surge protector as a backup for use at the pedestal, and what he had just explained seemed to indicate that could be useful in the event of an E10 power surge where you know the EMS surge protection has damage, but is still functional.  He acknowledged that it could, and that some people continue to use one at the pedestal routinely as "extra protection", but that he wasn't recommending it or not.

So, I'm not sure what we will do as for using the old surge protector for extra protection or just as a backup.

BrianZ

After thinking on this a bit more, if I ask the question again, "Should we continue using the old surge protector at the pedestal, or keep it for backup if the EMS is damaged or loses its surge protection?" but assume the worst result in each case, then the answer is clear..

If both were in use and both destroyed, then I'd need to rewire the cable to bypass the EMS and get power back, but without any means of protection left.
If the old pedestal surge protector were kept as backup, the destroyed EMS would still need to be rewired, but we'd also still have the basic surge protector for use at the pedestal, as well as its diagnostic lights for detecting a miswired pedestal if we needed to move to a new one.

However, we should probably still plug the old one in first, by itself (as we normally do), just to detect a miswired pedestal, but then remove & store it before plugging in the T@B cable.
Agree?

Dutch061

@Brianz , I am on RV number 4 with our 2020 TAB 400 BDL and this is the first one I have ever bothered with even using any type of electrical protection. The only reason I decided to install the EMS-HW30C is because this is the last RV I plan on ever owning and we plan to spend a few months per year traveling, if we ever get started. I thought for the minimal investment (in comparison to replacing everything that could be damaged) it was worth the money and my time to install it. Even though we rarely plug into a power pedestal anywhere, it provides some good information and also the safety factor. 

With that being said, life is way too short to stress out about "stuff" this much. Quit worrying about having a back up for surge protection or having to have a portable to plug in to check the power first. After all, this is exactly why you installed the EMS-HW30C isn't it? Enjoy your RV and the time you get to use it. I mean in reality, we all should have a back up for everything; a second TV, generator, RV, the list is endless. But why, it is just stuff. 

Life can change in a split second and what you take for granted today can be forever gone....

Brad

BrianZ

@Dutch061,
Thanks for your viewpoint, Brad.
This is our first RV and might be our last as well, but we have used it quite a lot in the first 4 years & still enjoy every trip we make.  I enjoy making mods, and also the brain exercise in deciding how to best implement them.  Sorry if my mental gymnastics seems like worry and stress to you, but I do enjoy a bit of an exercise in logic.  We don't really need a backup for everything, but a new & improved version doesn't necessarily make the old version useless.  I'm sure there are plenty of campers who [wisely, I believe] check out the power pedestal before doing anything else, like with a non-contact voltage probe, or a plugin tester for other wiring faults.
No worries, just be safe!  We've had reservations to get back out very soon, so looking forward to it.

Dutch061

@Brianz, glad I am not the only one who has "analysis to paralysis" in their genes...

Brad

BrianZ

Since I had forgotten to address the reset time delay jumper setting on the circuit board, I can say we initially left it at the default position; but after asking Danby, the manufacturer of our window A/C unit, I will be changing it to the longer delay setting to allow time to switch off the unit for a while longer.  Danby suggested several hours.  See their reply here..
https://tab-rv.vanillacommunity.com/discussion/comment/171007#Comment_171007

We did survive a couple of brief brownouts during a recent thunderstorm with the A/C running & it came back on after the EMS reset & worked ok afterwards.  If there was any damage to the compressor, we haven't seen any evidence of it, as it continues to work fine.  For the same situation in the future, with the longer EMS reset delay, we will use that time to turn the unit off and let it rest for a while.

BrianZ

One last followup..
My write-up included a photo where I described using gaffer's tape to hold the data cable to the side of the wheel well.  The tape did not stand up to 90°+ temps, so I removed & replaced it with some half inch conduit..

Here's a link for the conduit, which includes an adhesive foam tape backing, and a snap-on cover..
https://www.amazon.com/dp/B07WZJGMST
Hopefully, this will do the job.  I had to use 2 pieces to get the length I needed, so I aligned them carefully end-to-end, then slid the cover of the longer piece down to overlap the shorter piece & hold them both together for a more seamless look.  This conduit is a nice small size for holding a single wire.