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1793
10-29-2008, 08:45 PM
I have a customer who is having the only 11 watt bulb "blow" about every three weeks. This one and only light is powered by an 88 watt transformer. This 88 watt transformer is the lowest wattage transformer Intermatic has, according to their website.

What can we do to make the bulb last longer?
stickboy1375
10-29-2008, 08:46 PM
I have a customer who is having the only 11 watt bulb "blow" about every three weeks. This one and only light is powered by an 88 watt transformer. This 88 watt transformer is the lowest wattage transformer Intermatic has, according to their website.

What can we do to make the bulb last longer?
Whats the voltage at the fixture? Can the transformer support such a small load?
1793
10-29-2008, 08:50 PM
Whats the voltage at the fixture? Can the transformer support such a small load?


Bulb, Lamp is 12v 11 watt.

Did not see anything that mentioned fewer lights.
Dennis Alwon
10-29-2008, 08:50 PM
I have a customer who is having the only 11 watt bulb "blow" about every three weeks. This one and only light is powered by an 88 watt transformer. This 88 watt transformer is the lowest wattage transformer Intermatic has, according to their website.

What can we do to make the bulb last longer?

Some transformer demand a minimum wattage. You may not have enough watts which may be causing an issue-- not sure how but....
stickboy1375
10-29-2008, 08:53 PM
Bulb, Lamp is 12v 11 watt.

Did not see anything that mentioned fewer lights.

Thats the voltage you read with the light on at the fixture?
1793
10-29-2008, 08:53 PM
... You may not have enough watts which may be causing an issue-- not sure how but....


Me either :roll:
Dennis Alwon
10-29-2008, 08:55 PM
Me either :roll:

Usually too low a wattage will make the light flicker which could cause a premature burnout.
hbiss
10-30-2008, 09:04 PM
This 88 watt transformer is the lowest wattage transformer Intermatic has, according to their website.

I'm not seeing an 88 watt but there is a 60. Anyway, have you measured the voltage AT THE LAMP? I suspect that because you have little load on the transformer the voltage output is going to be higher than what it is rated- which is with an 88 watt load and some amount of wire.

-Hal
mdshunk
10-30-2008, 09:06 PM
You're not hooked to the boost tap at the transformer, are you?

Many landscape lamps cross to an automotive lamp and handle vibrations and such a lot better, if you suspect that might be an issue.
Fishin-trician
10-30-2008, 10:23 PM
I had this same issue once. reread the manufacturer's specs and they required the first fixture to be no closer to the xformer than 10 ft., changed the wire layout and had no more problems with that fixture.
1793
10-31-2008, 08:45 AM
I had this same issue once. reread the manufacturer's specs and they required the first fixture to be no closer to the xformer than 10 ft., changed the wire layout and had no more problems with that fixture.

I'll try to get back to my customers to look at this and check the voltage at the light.
1793
10-31-2008, 08:49 AM
This 88 watt transformer is the lowest wattage transformer Intermatic has, according to their website.

I'm not seeing an 88 watt but there is a 60. Anyway, have you measured the voltage AT THE LAMP? ... which is with an 88 watt load and some amount of wire.

-Hal

This is the transformer my customer is using http://www.malibulights.com/index.php?action=subcategory&did=1&cid=4&sid=9&pid=ML88T
Oakey
10-31-2008, 09:13 AM
I had this same issue once. reread the manufacturer's specs and they required the first fixture to be no closer to the xformer than 10 ft., changed the wire layout and had no more problems with that fixture.
This helped me cure a similar issue as well. Also I cut the leads off the light and wired a tail to help make it easier to take a voltage reading, I'm assuming these are the lights with the compression clips.
mxslick
10-31-2008, 04:23 PM
As mentioned there is a minimum wattage one can connect to those transformers, I have measured an open circuit voltage of around 16-18vac on the typical transformers.

For an 88 watt transformer I would figure at least 20-25 watts to drop the voltage to 12-13 volts.

Or you can add a length of wire to drop some voltage too.
1793
11-07-2008, 11:07 AM
Voltage at the transformer is 12.1 and the same at the light, lamp.
The light fixture is about 11' from the transformer.

Anybody have any other thoughts on this?
stickboy1375
11-07-2008, 11:16 AM
Voltage at the transformer is 12.1 and the same at the light, lamp.
The light fixture is about 11' from the transformer.

Anybody have any other thoughts on this?

Cheap lamps and over voltage are the only things that come to mind.