Visit our Popular Forums

lsbrodsky · 11-01-2013, 01:05 PM

Please give me some reassuring advice? I did a search but could not find installation notes for a Trimetric on any recent 23/25/27 FB's. I really want this battery information but I do not want to tear my trailer apart to install the 2025 wiring.
Where did you mount the shunt? In the battery box or under the bed all the forward? Where did you install the display and most importantly, how did you pull the cable from the shunt to the display?
On my boat, I used to use #12 romex to pull wires through impossible places but I do not know whether that is possible on an Airstream.
Any advice would be appreciated!!! Thank you
Larry

dznf0g · 11-01-2013, 01:09 PM

FWIW, this is my install on my 30' classic. May help....may not.

http://www.airforums.com/forums/f449...ade-70932.html

lsbrodsky · 11-01-2013, 01:13 PM

Rich, I saw that but it looks like you have your monitor all the way forward, sort of just above the shunt connections. That is the bedroom on mine. Even so, how do you pull the Trimetric cable up through the wall?
Larry

dznf0g · 11-01-2013, 01:24 PM

Well, I didn't. Because everything is so close together (batteries, electrical center, etc) I just let the cable lay on the floor, along with all the rest of them) and ran it up inside the folding reading table by the door, and mounted the monitor with velcro on the mouse fur.

Where are your batts, electrical center, and desired monitor locations? Pulling through the walls is virtually impossible. I had this discussion with the mothership last week for another furnace wiring problem. They found me a work around which worked out well.

Does your unit have any under floor PVC wire conduit? Mine does on streetside that bridges the living room and the dinette.

A call to AS (Randy or Dan) may provide you with info and line drawings.

lsbrodsky · 11-01-2013, 01:37 PM

For my model year and config, the batteries are in a box outside the trailer on the A-frame, the electrical center is all the way forward, stbd, under the queen bed. Where I put the meter depends on what is involved in pulling the wire to it. The best location is in the galley with the other panels, but I guess I could live with the stbd side of the bedroom if getting the cable there is much easier.
I may need to call AS next week, but I am hoping someone has done this with a similar model trailer.
Larry

dznf0g · 11-01-2013, 02:04 PM

I would start at the electrical center. IMO the shunt should be as close to the batteries as possible to minimize the voltage drop from the batts as much as possible. So I would put the shunt on a wood or plastic panel close to the battery cable termination points in the electrical center.
Next follow the bulk of the main harnesses from the 12 center rearward. I'd bet they just run under the wardrobe, under the lavatory cabinets and under the galley counter. At any rate, that is where you could run your monitor cable. I'd also bet that there is a hole in the inner skin directly below the current monitors where your pump and tank monitor wires exit the wall under the galley cabinet.

I am just making my assumptions on typical AS methodology and the floor plan drawings for a 2013 Intl FB off the AS website.

Now for the tricky part....It would be difficult, if not impossible to just fish the cable up to the current monitor area, but you could tape (solder for strength) additional stranded wire to the monitor end of a pump feed wire. Pull the pump wire (with the new extension on it) down to the floor wall opening. Then tape WELL the trimetric cable to the pump wire at the solder area and pull the cable and pump wire back up the wall. There are likely cross rib(s) to pass through, so jiggling and patience is needed. Examine the outside rivet lines for clues. I suspect only one horizontal rib up to the current monitor level...maybe two.

After the cable and pump wire are out at the top, unsolder and connect everything up. The telephone connector bulk may give you problems, depending how many wires pass through the rib grommets. Also the pump wire may be in a taped bundle, which is a problem. I may only be feasible, once you cable is under the galley counter, to drill a good sized hole in the inner skin just below the underside of the counter top directly under the hole you will cut for the trimetric cable and fish a foot or two straight down. Again, examine your outside rivet lines for obstruction free fishing.

lsbrodsky · 11-01-2013, 03:39 PM

Rich, again, thank you. I will do some crawling around tomorrow and see what things look like behind the cabinets.
Larry

lsbrodsky · 11-01-2013, 06:13 PM

Surely someone has installed this in a recent FB???

Larry

lsbrodsky · 11-02-2013, 10:12 AM

Ok, I took the mattress off and the wood panel below it so I could get to the electrical center. Two each red and black battery cables come up through the trailer floor under the factory inverter, one each goes to the inverter. The other cables go off into neverneverland or whatever JC calls their routing concept.
As such, there is no place inside the trailer where the cable terminations are in close proximity and can be attached to a shunt, it seems. The battery box on the A-frame is not oversized by much but I believe I can mount the smaller shunt to the fwd wall of the battery box. Of course I will have to disconnect and remove both batteries to get in there.
I still have the issue of pulling the shunt cable through the floor penetration, along the floor of the trailer and terminate it at the display. I am going to think about the bedroom wall or the bathroom wall. There just is no good way to get it to the galley or the living area. Wish me luck!
Larry

steverino · 11-06-2013, 10:14 PM

I mounted my Trimetic on the living area bulkhead above the TV, I ran the sense wires through a piece of wiremold in the bedroom that I installed for my solar charging system.

Shunt was cut into the ground return at the 12v distribution panel under the bed.

See Solar Airstream | Traveling with the Silver Bullet for details.

In your case, with your 25FB, you may be able to run the wire from under the bed to the bathroom along the corner where floor meets wall; try hiding the wire behind the plastic coping. From there, through cabinets to the galley area... Just an idea.

Steve

lsbrodsky · 11-07-2013, 01:57 AM

Steve,
Thank you for the ideas. I am not sure that I can put the shunt under the bed as you did. I have the factory inverter and it is wired up such that a red and black pair go directly from the battery to the inverter. I have not tried to trace the wires to the panel under the bed but it looks like a second pair run to that. Consequently, to all possible DC current I am going to need to mount the shunt in the battery box and connect both black wires to the shunt there. I will be in the under the bed area to do that and it looks like running the sensing wires to the bedroom is easier, maybe the head, but the galley is an effort.
Larry

RickDavis · 11-07-2013, 06:55 AM

The shunt needs to go directly to the negative battery (ies) terminal. Anything now connected to the negative , including the inverter, needs to go to the other end of the shunt or it won't be metered.
Don't count on Airstream for advice . I have seen them install it wrong and a couple of us had to show them how to correct it on one installed in a friends trailer.
I did not mount my shunt, I just attached it with a 2 inch length of heavy cable to the battery post.
After several years I changed from the 500 amp shunt to a 100 for a more precise readout ( 10 ma instead of 100ma) but then I don't have anything that approaches a 100 amp load since I dumped the microwave as being unnecessary
Once you get past the hassle you will like it.

lsbrodsky · 11-07-2013, 06:59 AM

Thank, I did know that as I installed a similar Xantrex system on my boat. The AS is a little different because it has two separate negative cables entering the trailer, one to the inverter, the other to the converter. I intend to take both of those off their respective battery and put them together on the shunt. Of course the batteries are paralleled with another cable.
Larry

idroba · 11-07-2013, 08:59 AM

On my 20' FC with front battery box, I put the shunt on the negative cable in the box. I flattened a piece of 1/2 inch copper pipe, put it in a vice and twisted it 90 degrees, and drilled holes in it for the battery bolt and the shunt connection. The twist was to make the shunt lay flat so the cables would not touch anything else. I had to re route the negative cables so they all were fed through the shunt. There were two big ones, one for the main power, the other for the inverter power. Sorry, no photos now, as I am not where the trailer is.

The cable I used between the shunt and the actual tri metric monitor was a simple piece of cat 5 phone cable. I placed a small fuse in the positive tri metric feed line and located it in the battery box. I was able to get the cat 5 into the trailer by snaking it along side the other wires which the factory installed and go to the electrical system under the front bed. From there I just found a way to get the wire to a closet interior where I have the actual monitor. Again, sorry for no photos.

lsbrodsky · 11-07-2013, 09:23 AM

Thanks, I had not thought of in-line. I have a similar plan with the shunt mounted on the fwd wall of the battery box. I will have to look at vertical clearance above the batteries to see if I can fit it in-line. Very helpful suggestion.
Larry

idroba · 11-07-2013, 09:46 AM

I thought about the shunt mounted in the battery box, but in the spring I want to change to a pair of golf cart batteries, which will require making the box taller. With the lips etc, it is too difficult to fit the batteries and the shunt into the limited side spaces. So, the top mount works out well. Again, a piece of half inch flattened copper pipe with a twist and holes drilled in it worked out very well for me.

nwmsmith · 05-18-2014, 01:34 PM

What ended up happening? I have a 25 ft FB, and am ready to tackle the project. Where did you end up mounting it? Did you pull wires? Did you also deal with the sun explorer monitor?

idroba · 05-18-2014, 04:19 PM

Since my posts above I have put in golf cart batteries which required raising the box height a bit and re locating my wires. I now have photos to show what I have done.

The first photo shows the top of the batteries with the shunt on the far left side, laying sideways in the negative side of the wiring. As I mentioned before, I used a piece of flattened copper pipe, with a twist and holes drilled into it to both do the electrical attachment and the physical mounting. BTW, the center two large wires between terminals are the old red and black AS wires to strap the 12 volt batteries together. I simply re used them as the connection between the two 6 volt batteries. A small fuse shows (blue wires), it is for the power to the tri metric meter. The other fuse goes to the power jack. Also note that there are two large red wires (+) and two large black wires (-) as my rig has the inverter option which has it's own wires directly tied to the batteries.

The second photo shows the shunt up closer.

The third photo shows how I raised the top of the battery box. I used 1 1/2 inch c channel aluminum and the original box lid.

The forth photo shows the blue plastic I lay over the top of the batteries, as a just in case situation to guard against shorts from the aluminum box top as well as some water and dirt protection.

BAB · 05-18-2014, 06:23 PM

I had just enough room to install the shunt in the battery box -- next to the two Lifeline AGM's. "Just enough" means that if I need to remove a battery, I have to "deinstall" the shunt. I weighed this carefully and decided that having it right next to the negative terminal far outweighed having to undo it if I have to pull a battery. Hopefully, with the AGM's that isn't going to be for at least three years. While you have a FB, I was able to put my monitor on the wall just adjacent to my electrical panel and pull wires quite easily. Lucky, I guess.

gandttimes · 08-14-2014, 03:48 PM

Quote:

Originally Posted by lsbrodsky

Thanks, I had not thought of in-line. I have a similar plan with the shunt mounted on the fwd wall of the battery box. I will have to look at vertical clearance above the batteries to see if I can fit it in-line. Very helpful suggestion.
Larry

Noticed your post after I did the install and wondered what you ended up doing? I did consult Bogart Engineering and it was strongly suggested that I mount the shunt under the bed away from any possibility of moisture. Had to rearrange some if the electronics ( I have the same setup as you) but in the end was able to reroute all the cables and attach to the shunt.
I feel better knowing it will be dry under there.

George