Not sure if this is complete. If anyone else reads this and sees something I've missed, please chime in.
a) Put the coach in Store mode, where the red light is on. This is needed for working on the battery cables, as if it is on and you remove the negative wires (ground), you can burn out your LVD.
b) Engine off, so no charging coming from there.
c) Shore power NOT plugged in, so no charging from there.
d) If you want to be super-safe, you can throw a blanket over the solar panel, so no power charging from it.
e) Take off ALL jewelry from both hands. This INCLUDES wedding band.
This step is important because if you have metal on your hand/fingers and accidently touch a positive cable to it, you can get shocked and burned. It happened to a service tech while I was in a RV repair center once, and he got a nasty burn around his finger because of his wedding band, which he'd forgotten to take off. So long as you have no metal and are not working in wet weather, you should be fine so long as you don't let a wrench or screw driver or something lay across both positive and negative cables at the same time.
f) When removing a lug from its position on the battery, unless I'm moving it to somewhere else right then, I always immediately wrap a little plastic baggy or two around it (I have small ones that are just a few inches square). This way if the cable gets pushed out of the way while I'm working, I don't accidently push it into something like a cable/battery pole of the opposite polarity and cause a short (as in Boom, sparks, bad things!). If you have little rubber caps or something, that'd be even better. Otherwise wrap some electrical tape around the lug. Generally speaking, try to only work with negative or positive cables at any given time.
g) Your batteries are hooked up in parallel. This means they output 12 volts, and the sum of the amps of the two of them. You can tell this because the black cable goes between the negative poles. If they were in series, then one battery's negative would connect to the other battery's positive.
All the negative wires coming in to the top battery are also connected to the bottom battery's negative by the short black cable. Technically that 12" cable means the first battery has slightly less resistance involved in power coming/going, so it will be used slightly more, and wear slightly more/faster than the second battery. If there were enough space, or fewer positive cables, then you'd want all the positive cables going to the second battery, with just a single positive cable between it and the first battery - this way the overall distance travelled from any device/charger would be the same, either 12" longer on the outgoing positive side or 12" longer on the incoming negative side. You can see that someone did try to put all the larger cables on the bottom battery, so its close to perfect positioning.
Now regarding installing your new shunt.
Nice pictures. The shunt has 2 large bolts on top, these are for the negative wires.
1) You need to find a place to mount the shunt. I don't think you want it free standing, just held by the large black cables on each side, as vibrations over time might make things come loose. I mounted mine to the fiberglass wall of the compartment (after figuring out where it fit best with the 3 incoming cables).
2) You move the 3 large black cables coming in to the top battery in the 3rd picture over to the left of the large bolts on the shunt.
3) Then make a new short black cable and attach one end to the free right bolt on the shunt, and the other end to where the 3 incoming cables used to go on the top battery. So you now have the shunt in between the incoming cables and the negative pole of the top battery.
Make the new short cable as large a gauge as the black cable going between the two batteries (or larger). And make sure its lugs are attached tight and correct. If you don't have the tools, you'll need to find someplace to create the short cable for you. Note that if the lugs aren't attached tight and solid, there can be extra resistance and they could heat up when in use, and eventually even melt their insulation.
4) Now you need to connect the included small red power wire going from the Batt+ on the shunt to the red positive pole on either of the batteries. Looks like your positive poles are already very crowded with lugs, so good luck with that
- Note, I have a similar shunt from Victron and the brass hex head screw that came with it was too short when I attached 2 large 4/0 cable lugs (it wouldn't screw in enough to make me think it'd hold them tight over time, with all the bouncing when driving, especially as brass is a soft metal). If this happens to you, then know you can buy the exact same screws at McMaster-CARR. They ship fast and their pricing is reasonable, and shipping is decent, and though they don't calculate it until after your order, I found you can trust them. Brass Hex Head Screw, M10 x 1.5 mm Thread was my size, though double-check your manual. You'll need to decide on the length - I bought a couple each of 20mm, 25mm, and 30mm, and then just tried them with my lugs until I got the perfect length for a tight solid fit.
Code: Select all
small power cable
|------------------|
---\ + |
----Shunt-------Battery-1 +
---/ | |
| |
Battery-2 +---- red positive cables going out
\-----
