inductive?

Yes.

AND then the possibility of inductive coupling starts to make sense.

However one could use a retractable cable reel; that wouldn't have a hanging loop.

In fact this is basically it:

Owain

Well a smaller hanging loop as the weight of the cable will make one form. B-) I'd assume that out of the box it doesn't normally retract until the "pull and release" mechanisum has been activated. That would need disabling.

Have you been to Bill's property?

The industrial solution is a cable carrier

SteveW

The problem with so much bright lighting is that people will mistake it for the pub next door and keep driving into and damaging his gate!

Use low voltage and just use bare contacts. Rubbing ones make them self cleaning. As on tail lights of some cars. Or "lift off" electric kettles.

That would be quite difficult, I think, by the time everything is weatherproofed. Mechanical coupling might be easier - motor on the gatepost operated by microswitch coupling to a generator on the gate.

Or a hose and a water wheel.

Instead of LEDs use phosphors which are illuminated by ultra-violet lasers. The lasers are fixed and only illuminate the phosphors when they're in gate-closed position. Can't see the problem.

Cheers

How would the LEDs be powered?

Bill

It's a string of 500 LEDS that together pull 24W.

Bill

I started off wondering about solar but for a 12/12 hour duty cycle the requirement would be about 0.3kWh per day. Unfortunately the gate area doesn't get much sun. The back of the gate does face south but trees and buildings screen it most of the time in winter.

Bill

I'd like to do it that way but it would be hard (for me) to make something that would do it, and would withstand all weathers.

I could use ground return of course. The gate wheels are steel, not plastic.

Hmm...

Bill

This seems very promising, thank you.

Bill

Just coat the gate with radium paint ... simples

Neons and an electric fence energiser?

Pretty *and* secure.

Owain

What about reflective strip on the gate and a light from a fixed location that illuminates the strip? What is the primary purpose of illuminating the gate with leds? Is it to make it visible to people approaching it, or for the lights on the gate to illuminate the surrounding area?

Well, I've got an open mind. Sliding contacts would be a nice simple solution. The positional accuracy of the gate is very good near the wheels, so it might be possible to do something. Trouble is, if I mounted something low down it would probably get mucky and wet.

Bill

The safety sensors on the gate are connected to 433MHz transmitters that emit a brief signal when activated. The signal is picked up by a receiver that communicates with the gate motor's control panel. In addition there are fixed IR beams across the drive entrance.

Bill