How to Connect Devices to the RV-C Network
The diagram below outlines the basic RV-C network layout. The Firefly Gx panel has a 12 volt power supply feed and this is where the switching and dimming takes place for the lights (or other devices) as shown to the left of the diagram. The right of the diagram shows the RV-C network. The blue line is the main Trunk, note the ‘T’ at each end of the trunk indicating a 120 ohm termination resistor. There are only 2 terminations allowed per network, one is located at each end of the Trunk cable. The green lines are Drops, these connect to wall switches, shade controllers, tank level sensors and whatever other RV-C devices are in the network. Drop cables must not be terminated and are technically limited to about 6′ in length.
Not shown in the diagram above are Drop Taps – these will be located where the green Drop cables meet the blue Trunk. Connecting eRVin (a RaspberryPi with an RV-C compatible “CAN” board) or any other RV-C device to the network can be at any location with a Drop Tap.
The Drop Tap shown below is over the entry door. The two green cables are Drops, The orange connector at the bottom connects to the Trunk. This Drop Tap has 4 Drop sockets, only two of which are being used. This Drop Tap also happens to be at the forward end of the trunk, so is a version with a terminating resistor built in.
On my Entegra Aspire, taps can be found in the following locations:
The under the bed tap is a “Common Drop Tap” and has no termination resistor. Also it placement is unusual and not entirely “legal” because it is not connected directly to the Trunk and is being used to create a Drop from another Drop cable.
On the back of the G6 panel there are several more open connections. On my Aspire there were 12 sockets total and 7 of those were open. Note the termination resistor at the bottom left of the photo – there are three more empty drop sockets behind it.
Normally the easiest place to plug in your eRVin system is to the Net Port on the front of the Gx panel. Keep in mind you want it in a location that will ensure even WiFi reception throughout your rig. Also it is best to keep it in an area not subject to temperature extremes such as over the entry door. Other devices such as with the SeeLevel upgrade will most likely plug in directly to the back of the Gx panel.