Wheat Lamps

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siquelme
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Wheat Lamps

Postby siquelme » Mon Oct 06, 2014 9:35 pm

Good evening,

I recently purchased some lights from Kytes lights (never had issues before and i suspect its my wiring thats the issue), I have tested the circuit with LEDS and it works perfectly but when I add the lamps i purchased nothing happens.
These are the lamps I purchased (http://www.kyteslights.com/product_info ... ucts_id=76) am I missing something stupid

Cheers

Simon
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Flashbang
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Re: Wheat Lamps

Postby Flashbang » Mon Oct 06, 2014 10:00 pm

Hi
You haven't mentioned how many new filament lights are being added?
Many of these filament lights consume between 60 and 70 milliamp each. So it's very easy to overload the power supply feeding them. LEDs only consume around 10 to 20ma per lit LED.

I note from your wiring you're feeding the point motor CDU, other lights and the new ones all from the same PSU output! It's far better to use two seperate PSUs. One for lighting that's rated at 12 volts and had a regulated dc output and another for the CDU at 16 volts ac. For lighting, I would be looking at a PSU with a 1.0 Amp minimum rating.
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siquelme
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Re: Wheat Lamps

Postby siquelme » Mon Oct 06, 2014 10:20 pm

Hi Flashbang, thanks for the reply. I am literally just adding 1 filament light to the 2 LEDs that are already on the cicruit. I was going to invest in a new PSU but was going to do it once the layout was more advanced seemed a bit silly in my getting 2 PSU for 4 point motors and 3 strips of lights. I will unwire the whole set up and just add the filament lights set up direct to the power supply to see if that is the actual issue.

I was looking at getting one of these (http://www.kyteslights.com/product_info ... cts_id=259) but it looks like a laptop so not sure how you could wire it all.

Cheers.
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Flashbang
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Re: Wheat Lamps

Postby Flashbang » Tue Oct 07, 2014 10:52 am

It is a regulated 12 volt dc power supply capable of providing 5.0Amp at 12 volts, which is a heck of a lot of current for lighting a few lamps!

Personally, I would look at obtaining a 12 volt dc regulated PSU from somewhere like ebay. Example... ebay PSU -1
ebay PSU -2 This one offers a 1.5Amp output which will be able to power approx. 20 filament lamps or about 80 LEDs or a mixture of both.
You either cut off the low voltage moulded plug and connect the two wires to a terminal block or IMO it better and easier to leave the plug and obtain a matching dc socket of the same size. Typical example of an easy fix version that matches the plugs on the two PSUs linked above...
ebay dc line plug with terminals
ebay line socket with wires
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Emettman
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Re: Wheat Lamps

Postby Emettman » Tue Oct 07, 2014 11:48 am

siquelme wrote: I will unwire the whole set up and just the filament lights set up direct to the power supply to see if that is the actual issue.


That should do it. The resistor which is letting the LED's work with 12 volts (by making it not 12 volts as far as the LED is concerned) is ruining it for the bulb that wants 12 volts... Or possibly only six volts. It will depend on the bulb, but see what 2 bulbs in series looks like on a circuit supplied with 12 volts: they may give a warm gentle light rather than be searchlight bright, and they will be liable to last an awful lot longer before burning out.

Otherwise the 12v bulbs need to be wired in in parallel to the supply.
(if the above looks good, then it will be pairs of bulbs in series, then wired in parallel.)

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Bufferstop
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Re: Wheat Lamps

Postby Bufferstop » Tue Oct 07, 2014 12:37 pm

Unless it says differently on the bulbs they will be rated at something between 6 and 16v. If they are wired in series pairs in the lamps they will already be running on roughly half power. If the resistor is the same value as used for the LEDs nothing visible is going to happen. The current they draw will be too low to raise a glow. Simply connect them between the switched wire and the return terminal. If they are quite bright then wire the lamps as, pairs in series, across the two wires, then they will glow like n old fashioned gas lamp(ie a bit pathetic)
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siquelme
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Re: Wheat Lamps

Postby siquelme » Tue Oct 07, 2014 8:40 pm

The bulbs have a sticker on them saying "12 Volts" so assuming thats the voltage.

Rigged up the wiring and put the lamps on direct to the the PSU and it worked perfectly so will be getting another one like Flashbang suggested. I was wondering if the adaptor is regulated would I need resistors on the circuit? If everything is 12 volts and the power is 12 volts would they be required?

Thanks again and really greatful for the help
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Re: Wheat Lamps

Postby Steve1414 » Mon Nov 10, 2014 4:44 pm

The resistor in the circuit is probably lowering the voltage to the leds down to something like 2 volts which is why the 12v lamps dont light.

If the bulbs are rated at 12v and the supply is 12v then all should be well. remember that if you lower the voltage by only a small percentage you will increase the life of the bulb. There must be a ratio thingy somewhere that works it all out.

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Re: Wheat Lamps

Postby bnb » Mon Nov 10, 2014 6:05 pm

Maybe if you rewired it slightly so that the wheat lamps bypassed the resistors
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Flashbang
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Re: Wheat Lamps

Postby Flashbang » Mon Nov 10, 2014 6:55 pm

Unless I have missed something the redrawn circuit now has a switch to a resistor and nothing else in that part of the circuit?
Somewhere either before or after the resistor an LED needs adding.
The Yard light if LED now doesn't have any resistors!

If the filament lamps are rated at 12 volts then no resistor is needed in their feed path.

LEDs if not rated at 12 volts must have a series resistor. Ideally one per lit LED, though one resistor can be used for several LEDs if the LEDs are connected in series (daisy chained), but then if one fails they all go out in the chain! Series is connecting one LEDs Cathode (negative) wire to the nexts Anode (positive) wire and do on.

As the original question was asked just over a month ago it's quite likely the problem had now been resolved?
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