SCR? solid state relays

I need to have a device that will make the turn signals, and marker lights on a trailer a seperate circuit from the truck.  I would like to do this without using mechanical relays.

I am needing to use something solid state, I believe SCR's would be the correct application for this

Could anybody send me a schematic or at least provide me with some part numbers?  I think a 20amp or better RMS rating will do

SCR's will Latch with DC.

Transistors Could Do the job

Exactly what are you trying to do?

But how would you Charge the Battery on the Trailer?

Trailer Isolator

http://www.vpaccessories.com/Trailwr.jpg

http://www.kriss.com/signalcontroller.htm

The battery will be on trucks still I just need higher capacity circuits to run all the lights on the trailer(s).  I could do it with relays but, solid state would be nicer.

Left Turn/Brake

Right Turn/Brake

Marker Lights

I will use the truck feed for these lights to trigger what ever it is I will use.

Thanks

I am slightly confused on the diagrams where does the load connect? 

I will be feeding whatever I use with a fused 20-30 amp circuit.  Then the unit will feed the trailer plug in.  The truck wires will be used for the trigger.

I don't see where the higher current would come into play here?

Ok thought about it some more, I need a circuit that will switch the positive with a positive trigger.

I am thinking it will take two transistors to do this right?

I think I need to use a positive switch for the load with a smaller transistor as a negative switch to get my positive trigger changed to a negative trigger.

Am I on the right road here?

Yes you are on the right track.

And the Light Bulb is the Load

What would be a suitable smaller transistor to use for the trigger, since it will not have the current flow the load will.