I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Bill Wright wrote

I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Should work fine. Dunno how buyable it is tho.

On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

https://hackaday.com/2019/05/28/wire...make-your-own/

On Sun, 24 Nov 2019 15:22:41 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Should work fine. Dunno how buyable it is tho.

So why don't you shut your senile gob, if you know nothing about it? tsk

--
addressing nym-shifting senile Rodent:
"You on the other hand are a heavyweight bull****ter who demonstrates
your particular prowess at it every day."
MID:

On Sun 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.


Magnetic switch if close enough, or some form of proximity sensor if
farther away? Look at burglar alarm kit - plenty of that sort of thing.
You might need to incorporate a small relay or transistor switch to
handle the current though.

--
Woody

harrogate three at ntlworld dot com

On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be suitable?
Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ

Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

--

Jeff

Bill Wright wrote:

I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.

Bill

What about solar?

See BigClive's solution. Needs water proofing though.

https://www.youtube.com/watch?v=AEnYRXr1_ww

--

No.
I don't think one could do this in any efficient way.
I'd have thought some kind of simple mating connection would work fine at a
low voltage. If you want them on when the gate is open but its only open for
a while then one could use a UPS on the gate with the connection connecting
the charging.
To do power transfer well seems to require HF AC at quite a high current
from what I recall. Looking at the inductive chargers for smart phones they
do seem to have a lot of electronics involved in the detection of the tuned
reception system as well. The question is, is the use case worth the hassle
of building something big enough.

Note crosspost removed to satisfy Albersani server
Brian

--
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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Bill Wright" wrote in message
...
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut they
are close together and the LEDs come on. The power requirement of the
lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Woody wrote:

Bill Wright wrote:

I want to put some LED lights on my sliding gate.

Magnetic switch if close enough, or some form of proximity sensor if
farther away?

That seems to completely avoid the question of how the power jumps over
to the gate ...

I think his issue is that in order to connect the lights on a sliding
structure, he needs a long bit of cable, susceptible to damage, hence why he
wants it to be wireless.
Many years ago, and don't try this at home folks. I saw an electric
helicopter being powered by a microwave beam from a modified oven. I somehow
think that the power loss and danger involved in powering leds this way
might be a slight issue though.

I still think some sliding contacts are the best bet myself, Low voltage, so
no danger and if shrouded well, will probably last for years assuming the do
not corrode, the sliding motion may keep them clean.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Woody" wrote in message
...
On Sun 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.


Magnetic switch if close enough, or some form of proximity sensor if
farther away? Look at burglar alarm kit - plenty of that sort of thing.
You might need to incorporate a small relay or transistor switch to handle
the current though.

--
Woody

harrogate three at ntlworld dot com

On 24/11/2019 09:27, Andy Burns wrote:
Woody wrote:

Bill Wright wrote:

I want to put some LED lights on my sliding gate.

Magnetic switch if close enough, or some form of proximity sensor if
farther away?

That seems to completely avoid the question of how the power jumps over
to the gate ...

Mmm.

Thet set me thinking alomgh te lones of a pair of contacts that are
m,ade when the gate is fully (open? closed?) that charge a BATTERY on
the gaste that powers the lights.


--
"Nature does not give up the winter because people dislike the cold."

ۥ Confucius

Its the wattage that will be the killer.
Brian

--
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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Richard" wrote in message
...
On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

https://hackaday.com/2019/05/28/wire...make-your-own/

Bill Wright wrote:

I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

You can buy 'commodity' induction coils in the 5W to 10W range that are
intended for phone charging, rather than running the LEDs on 'live'
power, maybe you could fit a battery on the back of the gate, and let it
charge 24x7, if the gate spends a significant part of its life open,
then have two receivers, so that its powered when fully open and when
fully closed

e.g. a 5V 1A transmitter/receiver
https://www.seeedstudio.com/Wireless-Charging-Module-5V-1A-p-1912.html

a bit more googling ought to find 10W coils

I still think sliding contacts would be allot more efficient and less of a
hassle to weather proof.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Andy Burns" wrote in message
...
Bill Wright wrote:

I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

You can buy 'commodity' induction coils in the 5W to 10W range that are
intended for phone charging, rather than running the LEDs on 'live' power,
maybe you could fit a battery on the back of the gate, and let it charge
24x7, if the gate spends a significant part of its life open, then have
two receivers, so that its powered when fully open and when fully closed

e.g. a 5V 1A transmitter/receiver
https://www.seeedstudio.com/Wireless-Charging-Module-5V-1A-p-1912.html

a bit more googling ought to find 10W coils

Brian Gaff wrote:

I still think sliding contacts would be allot more efficient and less of a
hassle to weather proof.

You might be right, but that's not what bill asked for.

In article ,
Jeff Layman wrote:
On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be suitable?
Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ

Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

It's not 24w per led. It's 24w in total

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On Sun 24/11/2019 09:27, Andy Burns wrote:
Woody wrote:

Bill Wright wrote:

I want to put some LED lights on my sliding gate.

Magnetic switch if close enough, or some form of proximity sensor if
farther away?

That seems to completely avoid the question of how the power jumps over
to the gate ...

I misunderstood the question. Having said that, for safety reasons the
gate should have a bump stop on the leading edge so that if someone or
thing gets in the way the gate either stops or withdraws. Such gates are
heavy so need a fairly powerful motor (even if geared) to shift them
ergo if it didn't stop it could do damage or serious injury.
If the gate has such sensing then by definition it must already have
some form of connection to it so that the bump sensor gets its message
back to the controller, and if that connection exists then it shouldn't
be difficult to get power for the LEDs as well surely?

--
Woody

harrogate three at ntlworld dot com

On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

My electric toothbrush has a base which is connected to the mains and a
toothbrush which sits on the base to charge it. Effectively there is a
coil in the bottom of the toothbrush that charges the toothbrush battery
via a diode, and I imagine (I haven't dismantled one to find out) that
there is a similar coil in the base, though as it is connected to the
mains it will be a lot more turns of a much finer wire. When in close
proximity they form an air cored transformer, and the mains going in the
base charges the battery in the toothbrush.

In theory, a similar arrangement could light the diodes on the gate by
having one transformer coil on the gate and one on the gatepost.

There are some snags:
In order for a transformer to work (whether air cored or the more
efficient iron cored), you need alternating current going into its
primary winding. You will need either power originating from the mains
or a DC supply with an oscillator between power and transformer coil.

LEDs require DC, so you are going to need a rectifier in the gate
circuit, and unless you are prepared to put up with a 50Hz flicker it
will need to be a full wave rectifier, and ideally a smoothing capacitor
to protect the LEDs from spikes in the power input.

This is an outdoor gate, so you will have to make sure everything is
weatherproof. It can be done, but I would be inclined to look for an
alternative configuration: perhaps a battery pack for the LEDs on the
gate charged by a solar panel, and a proximity switch based on a burglar
alarm "door open" detector between gate and gate post? Or even a simple
plug and socket arrangement between gate and gatepost so that DC
arriving at the gate post gets to the LEDs on the gate when the gate is
closed and the plug and socket marry up?

Just as an aside, 24W is a lot of light from LEDs (it is roughly the
lumens equivalent to 4x60W incandescent light bulbs). Anybody shutting
the gate in the dark is going to get suddenly dazzled. Anybody opening
the gate and thus turning the previously lit LEDs off is going to find
themselves night blind for a couple of minutes.

Jim

In article ,
says...

Brian Gaff wrote:

I still think sliding contacts would be allot more efficient and less of a
hassle to weather proof.

You might be right, but that's not what bill asked for.

That doesn't mean it's not the best/simplest solution, though.

24W is a lot more poweer tha of the other LED ideas mentioned
and I would imagine that losses would increase rapidly if the
Rx/Tx spacing varied (and there has to be some play in the
sliding arrangement, no matter how good it is).

Carbon brushes would be ideal for one half of the sliding
contact arrangement.

--

Terry

Terry Casey wrote:

24W is a lot more poweer tha of the other LED ideas mentioned

But if a battery is added, then charging can be done 24 hours a day, and
the lights won't be on all the time, could be PIR or timer.

On 24/11/19 10:48, charles wrote:
In article ,
Jeff Layman wrote:
On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be suitable?
Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ

Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

It's not 24w per led. It's 24w in total

I know. That still equates to a couple of thousand lumens assuming
around 80 lumens/w for a typical "domestic" led.

--

Jeff

On Sun, 24 Nov 2019 09:29:08 -0000, Brian Gaff \(Sofa 2\) wrote:

I think his issue is that in order to connect the lights on a sliding
structure, he needs a long bit of cable, susceptible to damage, hence
why he wants it to be wireless.

A catenary cable from end of gate to post a foot or so away from the
rear of the gate should be resonably safe area but if the gate opens
more than twice the height of the gate the bottom of the cateanry
will touch the ground before the gate is open. Actually the less than
twice as you'd want some slack in the cable with the gate fully
closed.

I still think some sliding contacts are the best bet myself, Low
voltage, so no danger and if shrouded well, will probably last for years
assuming the do not corrode, the sliding motion may keep them clean.

I'm inclined to agree a mechanical solution is likely to be more
reliable and easier to install, if only because the weather proofing
requirements are almost non existant.

Corrosion can be elminated by choice of contact materials:

Stainless steel, recovered from the actual rubber blades of some old
wipers? Rather small, less than 1/8" wide.

Springy copper strip "Copper traditional draught excluder". I have
some, somewhere, but haven't seen it for quite a while. It wouldn't
have got thrown out that's for sure! Advantage is that it's about an
inch wide so easy to get a decent contact area and alignment. I could
be persuaded to go looking and pop a some in the post.

Brass shim sheet, might be available in the DIY sheds with the angle,
rod, tube other metal sheet stuff. But might not be springy enough.
My metalurgy isn't up to knowing if heat treatment/quencing would
make it springy.

Fixings, brass or stainless steel screws.

Or look at what is on offer for automatically
connecting/disconnecting electric fences across gates (hinged or
sliding). Might need careful selection of type and minor mods as an
electric fence is high voltage low current rather than low voltge
high current.

--
Cheers
Dave.

On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Same idea
https://www.mouser.co.uk/new/wurth-e...velopment-kit/

A FAQ suggests that the MAXIMUM spacing between coils is 10mm and damage
may occur when there is no load so when the coils are not aligned (maybe
even by a small amount) when the gate is moving the whole system may
have to be instantly switched off.

https://www.we-online.com/web/en/ele...spower_faq.php

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 24/11/2019 11:31, Andy Burns wrote:
Terry Casey wrote:

24W is a lot more poweer tha of the other LED ideas mentioned

But if a battery is added, then charging can be done 24 hours a day, and
the lights won't be on all the time, could be PIR or timer.

Yes.

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


--
"When a true genius appears in the world, you may know him by this sign,
that the dunces are all in confederacy against him."

Jonathan Swift.

On Sunday, 24 November 2019 11:49:44 UTC, Dave Liquorice wrote:
A catenary cable from end of gate to post a foot or so away from the
rear of the gate should be resonably safe area but if the gate opens
more than twice the height of the gate the bottom of the cateanry
will touch the ground before the gate is open. Actually the less than
twice as you'd want some slack in the cable with the gate fully
closed.

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

https://whiterosetools.com/products/...tlet-extension

An alternative is a coily flex (headphone type) with a retractable clothes-line through the middle of the helix to stop it dragging on the ground.

https://www.simbal.net/product-category/spiral-cables/

Festoon carriers are available to attach to the cable so the cable sheath isn't rubbing directly on the catenary

https://www.simbal.net/product-categ...-wire-systems/

Owain

On Sunday, 24 November 2019 12:26:23 UTC, wrote:
However one could use a retractable cable reel; that wouldn't have a hanging loop.

In fact this is basically it:

https://www.simbal.net/product-categ...spection-lamp/

Tie lamp to gate. Fix reel to post. Connect. Job done (at some cost, admittedly).

Owain

On Sun, 24 Nov 2019 04:26:20 -0800 (PST),
wrote:

A catenary cable from end of gate to post a foot or so away from
the
rear of the gate should be resonably safe area but if the gate
opens
more than twice the height of the gate the bottom of the cateanry
will touch the ground before the gate is open. Actually the less
than
twice as you'd want some slack in the cable with the gate fully
closed.

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

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.

--
Cheers
Dave.

In article , Jeff Layman
wrote:
On 24/11/19 10:48, charles wrote:
In article , Jeff Layman
wrote:
On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be
suitable? Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ

Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

It's not 24w per led. It's 24w in total

I know. That still equates to a couple of thousand lumens assuming
around 80 lumens/w for a typical "domestic" led.

Have you been to Bill's property?

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On 24/11/2019 11:49, Dave Liquorice wrote:
On Sun, 24 Nov 2019 09:29:08 -0000, Brian Gaff \(Sofa 2\) wrote:

I think his issue is that in order to connect the lights on a sliding
structure, he needs a long bit of cable, susceptible to damage, hence
why he wants it to be wireless.

A catenary cable from end of gate to post a foot or so away from the
rear of the gate should be resonably safe area but if the gate opens
more than twice the height of the gate the bottom of the cateanry
will touch the ground before the gate is open. Actually the less than
twice as you'd want some slack in the cable with the gate fully
closed.

The industrial solution is a cable carrier

https://www.wireandcabletips.com/cable-carrier-basics/

You see the same sort of things in many carwashes.

SteveW

On Sun 24/11/2019 13:10, charles wrote:
In article , Jeff Layman
wrote:
On 24/11/19 10:48, charles wrote:
In article , Jeff Layman
wrote:
On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be
suitable? Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ

Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

It's not 24w per led. It's 24w in total

I know. That still equates to a couple of thousand lumens assuming
around 80 lumens/w for a typical "domestic" led.

Have you been to Bill's property?

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!

--
Woody

harrogate three at ntlworld dot com

On Sunday, 24 November 2019 04:18:56 UTC, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

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.

On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

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
--
Clive

"alan_m" wrote in message
...
On 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Same idea
https://www.mouser.co.uk/new/wurth-e...velopment-kit/

A FAQ suggests that the MAXIMUM spacing between coils is 10mm
? and damage may occur when there is no load so when the coils are
not aligned (maybe even by a small amount) when the gate is moving the
whole system may have to be instantly switched off.

Thats a lot more power than he needs tho.

https://www.we-online.com/web/en/ele...spower_faq.php

On 24/11/2019 08:47, Woody wrote:
On Sun 24/11/2019 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.


Magnetic switch if close enough, or some form of proximity sensor if
farther away? Look at burglar alarm kit - plenty of that sort of thing.
You might need to incorporate a small relay or transistor switch to
handle the current though.

How would the LEDs be powered?

Bill

On 24/11/2019 08:49, Jeff Layman wrote:
On 24/11/19 04:18, Bill Wright wrote:
I want to put some LED lights on my sliding gate. I wondered if I could
power them inductively, with a power 'transmitter' fixed to the gatepost
and a power 'receiver' on the gate, positioned so when the gate's shut
they are close together and the LEDs come on. The power requirement of
the lights is 24W at 12VDC. The positional accuracy of the gate is good.

Bill

Have you considered whether or not ultraflexible wire might be suitable?
Such as:
https://www.amazon.co.uk/BNTECHGO-Silicone-Flexible-Strands-Stranded/dp/B01C5DBKW6/ref=pd_sim_60_7?_encoding=UTF8&pd_rd_i=B01C5DBKW6& pd_rd_r=7ab77a56-bb0a-4039-b629-0fa1c8b13a41&pd_rd_w=BSR9P&pd_rd_wg=uNhTl&pf_rd_p= 6a30fab2-6ed5-4400-920a-f4b0f59e4ff9&pf_rd_r=T3B1NZZ9C076EZM52RTQ&psc=1&re fRID=T3B1NZZ9C076EZM52RTQ


Just out of interest, why do you need the leds to be so bright? Leds
using 24W would produce give thousand lumens. If you need that light
level, why not have them fixed on posts?

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

Bill

On 24/11/2019 08:51, Ashley Booth wrote:
Bill Wright wrote:

I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.

Bill

What about solar?

See BigClive's solution. Needs water proofing though.

https://www.youtube.com/watch?v=AEnYRXr1_ww

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

On 24/11/2019 09:31, The Natural Philosopher wrote:
On 24/11/2019 09:27, Andy Burns wrote:
Woody wrote:

Bill Wright wrote:

I want to put some LED lights on my sliding gate.

Magnetic switch if close enough, or some form of proximity sensor if
farther away?

That seems to completely avoid the question of how the power jumps
over to the gate ...

Mmm.

Thet set me thinking alomgh te lones of a pair of contacts that are
m,ade when the gate is fully (open? closed?) that charge a BATTERY on
the gaste that powers the lights.


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

On 24/11/2019 09:47, Andy Burns wrote:
Bill Wright wrote:

I want to put some LED lights on my sliding gate. I wondered if I
could power them inductively, with a power 'transmitter' fixed to the
gatepost and a power 'receiver' on the gate, positioned so when the
gate's shut they are close together and the LEDs come on. The power
requirement of the lights is 24W at 12VDC. The positional accuracy of
the gate is good.

You can buy 'commodity' induction coils in the 5W to 10W range that are
intended for phone charging, rather than running the LEDs on 'live'
power, maybe you could fit a battery on the back of the gate, and let it
charge 24x7, if the gate spends a significant part of its life open,
then have two receivers, so that its powered when fully open and when
fully closed

e.g. a 5V 1A transmitter/receiver
https://www.seeedstudio.com/Wireless-Charging-Module-5V-1A-p-1912.html

a bit more googling ought to find 10W coils

This seems very promising, thank you.

Bill

Clive Arthur wrote:

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

Just coat the gate with radium paint ... simples

On Sunday, 24 November 2019 18:11:25 UTC, Bill Wright wrote:
I could use ground return of course. The gate wheels are steel, not plastic.

Neons and an electric fence energiser?

Pretty *and* secure.

Owain