Electrickery.

In the past I have seriously considered looking at the whole harness and wiring issue a little differently to what most people opt for.

The standard, and some might say tried and tested way, is to use relays to switch high current loads thus avoiding the need for high current capacity switches on the dashboard. In addition you will also find standard loom design requiring heavy capacity wires running from the relays to the front and rear of the vehicle to power the loads.

In the mass pro sector we use CAN bus, this system uses a messaging system from system ECU's to communicate with the central power distribution point so you no longer need a switch on the dash board that is capable of handling high currents. For example the heater control tells the heater fan to turn on using a message instead of actually switching the motor current in and out itself.

Anyway finally this type of technology has made it into the kit car world and the first unit which caught my eye was the Isquared 1+1 system on offer from www.isqe.com it does not appear to be what I would call a CAN system as it uses a single control module to a remote power distribution or smart fuse box. No relays here all switching via MOSFET's.


These images have been copied from another build site I found on the net:

http://home.comcast.net/~289fia_cobra/index.htm

After emailing Chris at ISquared I am now informed of a newer system called ISIS manufactured by Littlefuse which works more along the true CAN idea of a master controller connected to multiple sub power modules.

Each power module can control up to 10 loads. With this system the harness going from the front to the back of the car could consist of just +12V, Ground, the CAN lines (usually 2 wires in a twisted pair format) and any sender lines you may have. This instead of the normal tree trunk harness.

So for a Cobra you would most likely need 1 master module in the front and one power module at the back. No relays again.


So that's got me thinking again. Obviously I need to understand prices of both systems but I am warming to the idea, certainly with the 1+1 system fault finding will be so much easier as you can tell if the switch is working by checking the function LED on the power module.

Again watch this space, I may well change my mind totally and stick with the old ways or maybe not.....