For RV electrics and 230 V installation, special regulations apply. The whole is governed by the so-called. DIN VDE 0100-721 Data Sheet. It is about compliance with guidelines for the installation of electricity and the installation of equipment in the motorhome. Especially when self-development of the electrical system should be informed about the exact rules, so it does not come to a short circuit or defective devices later. Anyone who has already seen what a cable fire in a vehicle can do will certainly be interested in following these rules.
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Disconnect the battery
No matter what you want to install or change on your electrical system, the battery should always be disconnected from the system. Info: Always disconnect the negative pole first and then the positive pole. When connecting, first connect the positive pole and then the negative pole.
The whole thing has a simple background. If the negative terminal is connected and we are working with a wrench on the positive terminal, accidentally touching our wrench with the body could cause a short circuit. This can lead to damage to the motorhome electrical system. Also, high currents can flow through the wrench, which can result in burns or fires.
Cross sections of the power cables to be laid
Before laying the first power cables, you should think about the cable cross-sections. Which consumer do I want to connect to the wire and how much power does it consume? How far is the consumer from my power source? Only flexible cables (strands) may be used. Rigid wires are not allowed. Driving vibration can break stiff power cables and cause short circuits. Also, 12v cables and wires for the 230V installation must not be laid in the same cable duct.
Safeguarding the camper electrics
What you should not forget is the protection of the power lines. The fuse should always be as close as possible to the voltage source, in our case, the best AGM battery. The piece of cable that is between the battery and the fuse is not protected and may cause a cable fire when in contact with the body ground. It is precisely this critical area that we need to keep as short as possible.
We have protected our smaller leads for consumers such as LED, water pressure pump, 12V outlets, and refrigerator with the help of a fuse block.
The thicker power cables of the chargers are protected with glass fuses. These are available up to a current of 80 amperes.
Since our inverter pulls voltages beyond the 80A across the cable at full load, we have installed a strip fuse for this purpose.
Lay power cable and fuse for the 230V installation
For the 230V wiring, at least 1.5 sqmm H07 RN-F power cable with yellow protective conductor must be laid. We used 2.5 sqmm throughout the vehicle as we still had it in stock.
Also, only flexible cables (strands) are allowed.
These are suitable for wet rooms and outdoor use. So you’re on the safe side with the 230V installation in the motorhome. You can read our Best Trolling Motor Battery for the Money guide to buy your perfect motor battery.
An earth leakage circuit breaker is mandatory and should be installed for the shore power connection and the voltage transformer. An RCD circuit breaker has an integrated fuse with it. As part of the self-expansion, we have the two lifesavers in a fuse box for wet rooms housed. Even with the wiring of 230V, only strands may be used.
Only power cables with H07 RN-F are permitted for the supply of the shore power. Also, a minimum cross-section of 2.5 mm² is required.
Cable connections during self-assembly
There are different ways to connect the components of RV electrics. Luster terminals have lost nothing in my eyes in a vehicle. The glands can become loose during driving due to the vibrations and cause short circuits. If you still want to use them, you must use ferrules to make sensible contact. To process stranded ends with solder is also an absolute no go. Likewise the soldering of cable connections per se. Here again, there is a problem with the vibrations during the ride. Cable breaks can lead to malfunction of the electrical system in the motorhome.
Crimping tools and crimps are also a way to make connections safely. However, you should buy something reasonable and not 08/15 pliers from the hardware store. That only annoys you.
We use Wago clamps labeled 222 and 221. They are both suitable for connecting strands with different cross sections through the integrated clamping device. There is no need to use ferrules. If necessary, the power cables can be separated again.
The models 221 seems to me but now better suited for use in motorhomes. On the one hand, this is suitable for an ambient temperature of up to 85 degrees °, and the new model 221-613 can also accommodate a cable thickness of up to 6 mm².
For comparison, the 222 and 221-413 can only handle up to 4 mm². Also, the 222 is only released to 45 degrees ambient temperature.