DIYer has a lamp wiring question

[pirate]

Oh, really...?

I want some new bulbs/lamps
Here are some that are perfect!
No, there's 3 or 6 in a pack...
I only want 2!
Ermm...have the extras as spares?

Oddly enough, about 3 years ago I saw a lady in Homebase trying to find a single 50W halogen GU10...they were £2.50 each, but a 6 pack was a tenner...gotta feel for those on a limited budget, given 6 would have seen her out!
I bought the 6 pack, gave her 2 out of it in the car park...I mean, you would, wouldn't you?

I hate the way older folks are discriminated against that way. Go to Tesco...new steak slice waffle pastry thingies...2 for £2...but buy 3 and it's 6 for £3 effectively...but folks have a budget, don't want to eat the same thing 3 days in a row, can't store the extras...ffs, price them so everyone can benefit!
RANT OVER...sorry...

 

[brgrt2T]

Since you appear to want to use halogen lamps, then use halogen lamps. It is an easy solution and does not cause problems with transformers, dimmers, etc.
Be aware that you will be using approximately 90% more energy and that from about 2020 the halogen lamps will be unavailable following the energy efficiency measures applied by congress.
Cheapest LED I could find at 3000K not 2700K warmish but not as warm as halogen.

I can get the bulb as a single. I'll be going to Home Depot to look into the bulb and a transformer.

Thanks

 

[Richard Burns]

500lm should be a similar brightness compared to a halogen lamp.
Glad you can get the single LEDs, and I hope you can get a suitable DC driver for the lamps.

 

[brgrt2T]

500lm should be a similar brightness compared to a halogen lamp.
Glad you can get the single LEDs, and I hope you can get a suitable DC driver for the lamps.

Thanks

 

[brgrt2T]

Thanks

Can someone please supply the specs for the kind of LED driver I need. I get conflicting information about what I need. I'm even told I don't need a driver but a transformer.

Thanks,

Tamara

 

[Richard Burns]

Feit do not specify precisely the supply type needed: ac or dc.
Generally an LED will need a dc voltage, that sort of light bulb normally needs constant voltage, as opposed to constant current.
I attach the specification sheet for the type of bulb you may have.
This clarifies that each bulb is 6.6W and 12V.
Because you are running two of them at once you would need 13.2W as a minimum but this would mean you were running the power supply at maximum load, so perhaps a 15W or higher wattage supply would be better. Some examples of a simple plug in arrangement might be this one (24W) or this one (18W) the output is a 12V barrel plug which would mean you would either need to get a suitable socket to match and wire that onto the lamp or cut off the plug and carefully and safely join the cable to the lamp cable. other LED drivers may have flying leads to wire up to or just terminals to connect a plug and the lamp onto.
This may be something beyond what you wish to do, but is really as simple as it comes, however it does require some knowledge and a safe approach to electricity.
Occasionally manufacturers allow the bulb to work with 12 Vac supply, however if they are designed for dc the life time of the bulb will be reduced when using ac. A transformer would supply an ac output.

 

[brgrt2T]

Feit do not specify precisely the supply type needed: ac or dc.
Generally an LED will need a dc voltage, that sort of light bulb normally needs constant voltage, as opposed to constant current.
I attach the specification sheet for the type of bulb you may have.
This clarifies that each bulb is 6.6W and 12V.
Because you are running two of them at once you would need 13.2W as a minimum but this would mean you were running the power supply at maximum load, so perhaps a 15W or higher wattage supply would be better. Some examples of a simple plug in arrangement might be this one (24W) or this one (18W) the output is a 12V barrel plug which would mean you would either need to get a suitable socket to match and wire that onto the lamp or cut off the plug and carefully and safely join the cable to the lamp cable. other LED drivers may have flying leads to wire up to or just terminals to connect a plug and the lamp onto.
This may be something beyond what you wish to do, but is really as simple as it comes, however it does require some knowledge and a safe approach to electricity.
Occasionally manufacturers allow the bulb to work with 12 Vac supply, however if they are designed for dc the life time of the bulb will be reduced when using ac. A transformer would supply an ac output.

Thanks, Richard, for the information. I'll Feit on Monday.

 

[brgrt2T]

Thanks, Richard, for the information. I'll Feit on Monday.

Hi Richard,

Feit says the bulb is both AC/DC. It also comes with an internal LED driver. Apparently, most LED bulbs come with drivers and don’t need transformers. Thus while feit stocks halogen transformers, I’d have to look elsewhere for an LED driver. I guess drivers are so hard to find because most residential bulbs don’t need then.

I don’t understand the examples you provided of the kind of plug-in arrangement I could use. The page shows adaptors, not drivers or transformers. Are you saying I can use adaptors in place of transformers?

I was talking to an electrical supply place, and the guy was very surprised that my lamp was wired for 120 volts. He suggested that the lamp might have an internal transformer. Do you think that’s a possibility? I’m looking for a nearby electrician to have the circuit tested. Would I damage the lamp, or explode the bulb, if I popped in a 12V bulb to test the circuit?

You say in your last sentence that: “A transformer would supply an ac output.” But if the bulb has a built-in driver, would it work DC?

Thanks,

Tamara

 

[Richard Burns]

I think that it may be too complicated for me to attempt to explain the various means of using varying voltages.
If this is too complex to follow then it may be something that it would be safer to get the electrician to do if he comes over. It would take about 20 minutes, if he has the parts.
If you put a 12V bulb into a 120Vac light fitting then it will fail instantly. If your supply voltage is 120Vac then it is simple to have a lamp using that voltage and it would not have a transformer in the lamp.
Adaptors is the name given to a switched mode power supply that provides a dc voltage output in a similar manner to an LED driver, but they are more readily available and cheaper.
If Feit state that the bulbs can use ac or dc then you can use either an ac or a dc supply at 12V and the internal circuitry of the bulb will provide the correct input to the LEDs in the bulb.
Some halogen transformers have a minimum wattage required to run which may mean they would not work with only 13.2W load so if you buy one of them then check the minimum as well as the maximum load.

 

[brgrt2T]

I think that it may be too complicated for me to attempt to explain the various means of using varying voltages.
If this is too complex to follow then it may be something that it would be safer to get the electrician to do if he comes over. It would take about 20 minutes, if he has the parts.
If you put a 12V bulb into a 120Vac light fitting then it will fail instantly. If your supply voltage is 120Vac then it is simple to have a lamp using that voltage and it would not have a transformer in the lamp.
Adaptors is the name given to a switched mode power supply that provides a dc voltage output in a similar manner to an LED driver, but they are more readily available and cheaper.
If Feit state that the bulbs can use ac or dc then you can use either an ac or a dc supply at 12V and the internal circuitry of the bulb will provide the correct input to the LEDs in the bulb.
Some halogen transformers have a minimum wattage required to run which may mean they would not work with only 13.2W load so if you buy one of them then check the minimum as well as the maximum load.

Hi Richard,

I understand everything you wrote, but I still have a question. Can I pop a 12-volt bulb into my lamp to test whether my lamp functions at both voltages? My thought is that my lamp may have an internal transformer. If the bulb doesn't light, that gives me my answer. I just want to know from you that I won't damage my lamp or have the bulb explode in my face with this experiment.

Thanks,

Tamara

 

[Richard Burns]

If you put a 12V bulb into a 120Vac light fitting then it will fail instantly.

Hi Richard,

I understand everything you wrote, but I still have a question. Can I pop a 12-volt bulb into my lamp to test whether my lamp functions at both voltages? My thought is that my lamp may have an internal transformer. If the bulb doesn't light, that gives me my answer. I just want to know from you that I won't damage my lamp or have the bulb explode in my face with this experiment.

Thanks,

Tamara

A 12V bulb in a 120V supply will probably just light brightly for a fraction of a second and then burn out, it might go with a bang, it might trip the supplying circuit, it might explode, but not too likely, do not try this.

 

[brgrt2T]

A 12V bulb in a 120V supply will probably just light brightly for a fraction of a second and then burn out, it might go with a bang, it might trip the supplying circuit, it might explode, but not too likely, do not try this.

OK. Thanks.

 

[brgrt2T]

I think that it may be too complicated for me to attempt to explain the various means of using varying voltages.
If this is too complex to follow then it may be something that it would be safer to get the electrician to do if he comes over. It would take about 20 minutes, if he has the parts.
If you put a 12V bulb into a 120Vac light fitting then it will fail instantly. If your supply voltage is 120Vac then it is simple to have a lamp using that voltage and it would not have a transformer in the lamp.
Adaptors is the name given to a switched mode power supply that provides a dc voltage output in a similar manner to an LED driver, but they are more readily available and cheaper.
If Feit state that the bulbs can use ac or dc then you can use either an ac or a dc supply at 12V and the internal circuitry of the bulb will provide the correct input to the LEDs in the bulb.
Some halogen transformers have a minimum wattage required to run which may mean they would not work with only 13.2W load so if you buy one of them then check the minimum as well as the maximum load.

Hi Richard,

I hope this will be the last time I bother you with a question. But I want to make sure I understand what you say here:

“If Feit state that the bulbs can use ac or dc then you can use either an ac or a dc supply at 12V and the internal circuitry of the bulb will provide the correct input to the LEDs in the bulb.”

Are you saying that if an LED bulb can use ac or dc, I don’t need an LED transformer to step down the voltage in my lamp to 12 volts?

Thanks,

Tamara

 

[Richard Burns]

You can use either 12Vac or 12Vdc, you cannot use 120Vac or 230Vac.
That is what I mean when I say you can use ac or dc at 12V.

Just buy a transformer or driver or power supply or adaptor that will input 120Vac and will output either 12Vac or 12Vdc and will operate when it has a load of 13.2W i.e. its minimum rating is below 13W and it maximum rating is above 14W.
Then wire this into your power cable to the lamp: safely, in a box and with no strain on the connections, because the cable is clamped.
Plug in the light bulbs, plug in the power supply and the lamp should work OK.

 

[brgrt2T]

Hi Richard,

I finally rewired the lamp yesterday, and it turned out to be very easy. But here's the strange thing. The LED bulb is as hot as my halogen bulb. How is this possible? Do you think there is a problem with the rewiring?

Tamara

 

[Richard Burns]

A halogen bulb will operate at about 200°C external and 400°C internal and an LED bulb will fail when the LED exceeds 70°C.
An LED bulb will get hot, but only enough so that you would not wish to touch it for a period of time, not generally enough to burn you.
If the temperature of the bulb exceeds this then it will fail in short order.
A higher temperature would be experienced if the voltage was higher than specified but the bulb would not last very long and would be very bright.
If the bulbs are the same temperature as halogen bulbs then they are probably not LED bulbs but halogen bulbs.

 

[brgrt2T]

The bulbs are LED. You can search for the specs by entering: "feit bulb bpexn/930ca" into the search bar. The bulbs are so bright that I had to remove one, and even then the remaining light is bright. It almost hurts my eye.

Do you think the bulb is wacky or is something wrong with my wiring? I got the adapter that you linked me to.

Can the bulb ruin my lamp? I have to wait till after Labor Day to get in touch with the manufacturer, but I need the light till then.

 

[Richard Burns]

Led bulbs tend to have very concentrated light source that would be inconvenient to look at directly, but then again halogen are fairly similar in comparison to the style of bulb you have.
Brightness wise it should be a close match to a halogen bulb's brightness for illuminating an area, the beam angle is similar and the light output should be similar.
If the output is significantly brighter then I would feel there is something wrong somewhere but I cannot understand what could cause this, any errors in wiring should make the bulbs dimmer or fail to work, it would only be by supplying something like a 24V supply that the bulbs would be very hot and bright (and probably fail soon) but the type of power supply I suggested cannot supply a different output voltage, even if the input voltage were 240V the adaptor should be able to cope with this and still provide 12V output.
If the bulbs were wired in series in the lamp then they would be now very dim, if the adaptor was supplying 120V then the bulbs should fail instantly.
Possibly worth checking that the adaptor is a 12V power supply and not a 24V one and is also not one that has an adjustable choice of output voltages and been set on the wrong setting, usually a rotary or slide switch somewhere.
Other than that I am lost as to the cause.

 

[brgrt2T]

I checked the specs on the adapter, and they are as advertised. The output is 12 VDC, and there is no adjustment possible. I’m attaching its spec sheet.

I have another question. When I pulled the plug from the wall to check the specs on the adapter, one of the wires pulled loose. The connector holds only about ⅜ of an inch of stripped wire in its slots. (I’ve attached a screenshot so you can see.) I tightened the screws as far as they would go. Obviously, it didn't do the job. Should I put electrician's tape around the end of the wires? Does this connector sound safe to you?

Thanks,
Tamara

I have another question. When I pulled the plug from the wall to check the specs on the adapter, one of the wires pulled loose. The connector holds only about ⅜ of an inch of stripped wire in its slots. (I’ve attached a screenshot so you can see.) I tightened the screws as far as they would go. Obviously, it didn't do the job. Should I put electrician's tape around the end of the wires? Does this connector sound safe to you?

 

[DPG]

If the wires are pulling out of the terminal then I would try doubling the wire back, ie. so that there is twice the thickness of conductor.

Bearing in mind the issues you are having, I would be tempted just to buy a new lamp all together. It can't be worth all this surely?