Trimetric install on a TT, shunt can't be outside. Where did you put it?

[dagmandt]

Hi guys,

My trailer is still being built at the factory but it should be delivered the first week of April. I have my new Trimetric and Iota charging system sitting here waiting to be installed. I've been reading up on the Trimetric install specifically and while it is pretty straight forward I was told the shunt should not be out in the weather. Well, the shunt is supposed to be close to the battery and all the trailer negative wires are supposed to go to the shunt so this creates a wiring nightmare if I can't locate the shunt at the battery like can be done on coaches. Do you just send a cable up into the front pass through to the shunt then back out to hook up to the negative leads near the batteries?

What did you do on your travel trailer? I'm really not sure I want to go drilling a bunch of holes in mine to get this wired up.

Anyone have advice?

Thanks,
Darren

[Tony Lee]

Well, the shunt is supposed to be close to the battery and all the trailer negative wires are supposed to go to the shunt

My preference is not to have any unnecessary connections in the same compartment as the batteries.
Nothing to stop you running a short heavy cable from the battery negative to the shunt and then another short heavy cable from the other side of the shunt to the main grounding point.
If all your negative wires are terminated on the battery negative post at the moment it is very poor installation and would be good to change it anyway. Same if all the positives are terminated with fuses to the battery positive.

[Bruce Beard]

Originally Posted by dagmandt

Hi guys,

I was told the shunt should not be out in the weather.

Darren

Just out of curiosity, who told you it should not be outside?
I wired mine outside and although it is only one year old and inspected regularly it works just fine there in its somewhat sheltered position....
Bruce

[dagmandt]

Originally Posted by Bruce Beard

Just out of curiosity, who told you it should not be outside?
I wired mine outside and although it is only one year old and inspected regularly it works just fine there in its somewhat sheltered position....
Bruce

Backwoods Solar told me it shouldn't be out in the weather. I bought the Trimetric from them. I live in wet WA state, not sure if that makes a difference or not.

[dagmandt]

Originally Posted by Tony Lee

My preference is not to have any unnecessary connections in the same compartment as the batteries.
Nothing to stop you running a short heavy cable from the battery negative to the shunt and then another short heavy cable from the other side of the shunt to the main grounding point.
If all your negative wires are terminated on the battery negative post at the moment it is very poor installation and would be good to change it anyway. Same if all the positives are terminated with fuses to the battery positive.

I haven't got my trailer yet so I was making assumptions about the wiring going on the Trimetric install diagram.

[Tony Lee]

Never a good idea to have electrical connections of any sort out in the weather - especially if it involves salt on the roads.
The shunt has two high current connections and other very low current connections and ensuring consistent very low contact resistance is essential if accuracy is to be maintained.

[Shadowcatche]

I have a slightly oversize battery box with My Lifeline 150AH AGM battery and there was enough room that the shunt for my Victron is inside the battery box at one end. When they say short they mean short! The battery box is inside a tongue box and in reality its function is to protect the battery and electrical connections from stuff in the tongue box.

[elkhornsun]

There is a negative lead coming from the load side of the RV and connecting to the lead battery. All that is needed is to connect this lead to the shunt instead and run a short section of large gauge wire from the battery to the other side of the shunt.

There should be room to attach the shunt inside the battery compartment area to the inner wall where it will be out of the way when changing out the batteries. If you do not have space inside the compartment then I would look for a place on the other side of the compartment wall that is accessible and mount the shunt there.

There is no switching or anything to generate a spark with a shunt so no risk to putting it inside the compartment that houses the batteries. I added a cut-off switch circuit breaker with my installation and for this I used a marine CB from Blue Sea and mounted it on the other side of the battery compartment wall as it simplified the battery cable layout in the main compartment.

I added a temp sensor as well so its wire needed to be fished through along with the wires from the shunt. In my situation I could not mount the controller near the batteries and this complicated things enormously in terms of squeezing in connectors and switches and running large gauge wiring. Far easier is you can mount the controller on the other side of the battery compartment and then only need to run the wires for a remote input and display as with the Blue Sky controllers and the IPNremote.

[dagmandt]

Thanks for the info. My batteries are out in the open on the tongue of the trailer so I'll have to either put the shunt inside the pass through or find a way to seal it off from weather outside near the batteries. I'm not sure how far from the battery it can be and still be accurate/effective.

[emahan]

My batteries are on the tongue of my trailer. I mounted the shunt in a weatherproof electrical box on the trailer frame adjacent to the batteries. The cable entries aren't watertight, but it's much better than being totally exposed.