Polarity of LED 12V MR16 downlighters

[Speedy38]

Hi all
Was asked to fit two transformers for shop window display.
there was 8 12V down lighters in total split into two circuits and both switched through a timer,
The owner wants to replace the 8,12V dichroic MR16 bulbs with 12V MR16 LED 1.8w bulbs.
The reason he wants to replace the dichroic bulbs is due to the running cost also maintenance in replacing the transformers several times inthe past,

All fine with me however when fitting the new transformers ,one feeding 5 lights the other feeding 3 lights. due to window arrangement.
I was in the process of wiring the lights in parallel from the transformers & recalled the instructions that the polarity must be correct at the bulb, also that the bulb should have a ( + & - ) stamped on it showing its polarity.

Now I have the Polarity correct on the Trafo's and on the lamp connection point.
My problem/question is this.

The bulbs do not have the +\- stamped on them.
So what if any will be result of pushing the bulbs into the holders not knowing its polarity.
Secondly is there any way of testing the polarity of an LED bulb to ascertain its polarity.

I do not have much experience with LED bulbs hence my question.
any advice would be welcome.

Cheers.

 

[amlu]

transformers do not have polarity, they produce AC, only if you rectify their output with some diodes and capacitors you will get DC and + and -.
LED drivers do have polarity and should be used with 12v led strips, not mr16 lamps.

 

[Speedy38]

Te LED Driver/Trafo stated that polarity must be observed and provided info on the connection of the MR16 12VLED lights even giving the max total of 15 LED MR16 lamps per driver/trafo.
The lamps and the driver/trafo came as is from the supplierr, hence my question
Here is an example lamps supplied.

1.8 Watt MR16 White LED 12v GU5.3 Lamp| MeteorElectrical.com

 

[snowhead]

LED is a diode
A diode only allows current to flow in one direction
In the other direction it blocks flow.

So if you connect it up wrong it just won't light up, that's all.

 

[Speedy38]

Tank you snowhead just wanted to make sure I wouldn't cause a bulb to blow or a malfunction of the driver/trafo i did know what the LED stands for but haven't worked with them before I wasn't sure what effect wrong polarity would have on the fittings given the warnings on the driver/trafo.
Thanks again

 

[amlu]

led mr16 lamp will have some circuit inside, possibly rectifying ac to dc, for sure current limiting resistors for LED`s .
mr16 standard is for AC current, it does not have specitified polarity.
mr16 fed with a TRANSFORMER will have AC on its output.
led driver should be used with a suitable led light, not generic mr16 fittings, please post details of your transformer/driver please...

 

[Speedy38]

Hi amlu
Cheers for that I will be down at the shop tomorrow & I will get the details on the Drive/Trafo and post it up for you to view then.
.
going on your info it might be that the shop owner has been supplied with the wrong bulbs.
for the drivers/trafos supplied.


Thanks for your input I do appreciate it.

 

[Darkwood]

Nice to see a genuine question appropriate to the OP's experience and hopefully he is now a little wiser.... makes a change from some of the shocking questions asked by so called experienced competent electricians.

 

[shanky887614]

LED is a diode
A diode only allows current to flow in one direction
In the other direction it blocks flow.

So if you connect it up wrong it just won't light up, that's all.

L - light
E - emiting
D - diode

 

[telectrix]

L - lightE - emitingD - diode

do you want your coconut au naturel with hairs on it, or will a bounty do?

 

[Speedy38]

Hi all and thank you for taking the time to educate me on the LED aspect of things.
I was at the shop today and fitted the Drivers to the two circuits all running fine and no trouble.
I was just concerned that not having any experience in this realm that I might blow something electronic in the Driver or the bulb by inserting the bulbs the wrong way round +- in the lamp holders as recommended by supplier & ending up costing me money.
Turns out the Driver/Trao's were correct and at 1.8w per bulb each Driver rated at 16w I could put 5 on one circuit and 3 on the other.
I know it's uneven but as that is the way they are wired due to a doorway at shop front.
As promised here is a link to the type of Driver/Trafo supplied.

AU-LED16T 16W 12V DC Constant Voltage LED Driver AU-LED16T 16W voltage led driver [AU-LED16T] - £7.90 : Trade Electrical

Thank you all for your help and allaying my fears.

Regards.