Creating a good earthing point
Making an earthing point is a part of any installation with a leisure battery, or a mains hook up, so that covers pretty much all camper conversions.
It's really important especially when you're split charging as it will act as a part of the charging circuit, linking up, via the body of the vehicle to the main battery earthing. Without a good earth, you won't get the charge into the leisure battery.
Creating your earthing point.
This is something we intend to cover in a video soon, so I will just give a brief outline and then add the video once we've put it together. (11/08/2020).
The easiest way to get an earth is to use an existing thread or bolt hole on the vehicle, such as a disused seat belt mounting bolt, or the threads that hold a seat base. If you're using a pre-existing hole, please skip step 1 & 2.1. Locate a piece of the body work as close to your leisure battery as is practical. This should be an internal skin, so that when you drill it, you won't be opening the chassis to water or corrosion. (the part should be a double thickness piece of bodywork ideally and welded to the vehicle. This may be a high current connection, so it's important to find a good piece of bodywork (where the floor skin and inner quarter panel meet is usually a good place).
2. Drill a hole to match the size of bolt you're going to be using through the metal work (ideally 10mm), deburring the hole after drilling.
3. Clean the paint off around the hole, to at least the size of the largest eye terminal you plan to bolt down. This should be back to bare metal.
4. Apply a small covering of electrical grease, such as copper slip, to the bare metal area and both sides of the eye terminal.
5. Thread your eye terminal(s) onto an M10 (or whatever size bolt you're using) bolt and use a nut with a spring washer if possible to ensure it doesn't come loose, then placing the nut on the back, tighten through the hole.
6. To test, using a multi-meter set to resistance (ohms), check the new earthing point has a resistance of 0 ohms to a known good earthing point. Initially do this off load, then once you're satisfied that the earth is good. You can test the resistance under load. (By running the engine for a few minutes to allow some current through the new earth connection). Then repeat the resistance check (with the engine still running). This should give you a reading of 0 ohms.
We hope this helps.
Thanks for reading, have a great day!