((OT)) Electronics (electrical) Problem

On Wed, 30 May 2007 02:02:04 GMT, "Jeff Strickland"
> wrote:

>My meter told me the bulb was good, but now I am not sure about the meter.
>Maybe the meter is okay, but the moron working the buttons leaves a bit to
>be desired. In any case, the bulb is dead, and the original power supply is
>putting out voltage.


Two thing, a 40VA replacement transformer is not going to power a 250
watt bulb. Next, a 250 watt 24 volt bulb is going to read about a dead
short on ohm test (much less than 1 ohm) While it will look like about
a 1.5 ohm load when hot, resistance decreases when element is cold so
do not be surprized if it look like or near a dead short on a 1x
scale. BTW, a 24volt 250 watt bulb is a pretty serious bulb and can
get pretty warm.
-----------------
TheSnoMan.com

Jeff Strickland wrote:
> I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought
> a new one.
>
> The new transformer is stated to provide 40VA, but the light does not
> come on. My guess is that a VA and a "regular" A are different. What's
> the difference?
>
>

Just another thought for you.

I decided to fix the pool lights at my brother in laws cottage 'way' up
north and talked to a pool tech before going.

He stated the power transformers were the weak point.

This fiber unit used a 12 V 75W 'pot light' and a colored spinning wheel
but supposedly could take a 100W.

Sure enough, I didn't even need to meter the power supply once I saw the
melted solder on the output transistors. A new unit was pricey and I
'really' don't like replacing 'weak points' with 'new' weak points.

So I went into the local town to the hardware store, picked up a 120V
50W bulb (the biggest they had, no 75's), went across the street to a
Radio Shack and found a couple pigtails that fit the bulb's base because
no one had the proper pigtail in town and converted the sucker to a
'line voltage' box.

Basically I tossed out the 12 volt crap and just went 120V. It works
great and some day when I go back up if I get ambitious I will up the
bulb to a 75W or even the 100W the 'fixture' says it can handle. There
is a colored wheel to avoid melting.

The owners are fine with the lower 50W though so.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
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"SnoMan" > wrote in message
...
> On Wed, 30 May 2007 02:02:04 GMT, "Jeff Strickland"
> > wrote:
>
>>My meter told me the bulb was good, but now I am not sure about the meter.
>>Maybe the meter is okay, but the moron working the buttons leaves a bit to
>>be desired. In any case, the bulb is dead, and the original power supply
>>is
>>putting out voltage.
>
>
> Two thing, a 40VA replacement transformer is not going to power a 250
> watt bulb. Next, a 250 watt 24 volt bulb is going to read about a dead
> short on ohm test (much less than 1 ohm) While it will look like about
> a 1.5 ohm load when hot, resistance decreases when element is cold so
> do not be surprized if it look like or near a dead short on a 1x
> scale. BTW, a 24volt 250 watt bulb is a pretty serious bulb and can
> get pretty warm.


Yeah, I know it's a serious bulb. It gets seriously hot.

I have fiber optic lighting in my swimming pool. The light itself lives in a
box in a nearby planter, and there is a bundle of fiber cables that go from
the pool to this box in the planter. As the fan cools the lamp, there is a
color wheel that turns between the end of the fiber cable and the lamp, and
the pool changes color as the wheel goes around.

I didn't know the math to convert VA to regular A until somebody here told
me, and in the example they gave, the result is the same as the "regular A"
rating on the spec sheet. The catalog only gave the VA spec, and because I
did not know the math, the information given seemed adequate.

Adding insult to stupidity, my meter told me that the lamp was very nearly a
dead short -- as you said it should be -- and that the transformer I had
wasn't putting out anything. Now that I bought a new transformer, I find
that the lamp is toast and the old transformer is actually still good. I
haven't figured out if the meter lied, or I asked the wrong questions -- it
is loaded up with a **** load of buttons and input taps, and it seems now
that I may not have pressed the right buttons and filled the right taps.

After all this back-and-forth about the problem, all I can add is that Jeff
ought to not throw good money after bad, or incur further risk to himself by
calling in a really good electrician (not the guy who can replace a wall
switch) and leave it to him. We all think we know a little about
electricity, and it's just enough to get a surprise in the form of a lethal
or nearly lethal shock.
I'd just as soon not read the news and find that Jeff Strickland was found
face down with two wires in his hands. ....."let's see now, was that 250
Amps or 250 Watts???"
Stick to plumbing repairs. Lots of professional electricians have
succumbed to electrical shock, but I've yet to hear of a plumber drowning.

"Mike Romain" > wrote in message
g.com...
> Jeff Strickland wrote:
>> I thought I knew this stuff, but there is a nuance that I'm not getting.
>>
>> I have a fiber optic lighting system in my swimming pool. It takes a
>> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
>> The power supply (transformer) does not put out any voltage, so I bought
>> a new one.
>>
>> The new transformer is stated to provide 40VA, but the light does not
>> come on. My guess is that a VA and a "regular" A are different. What's
>> the difference?
>>
>
> Just another thought for you.
>
> I decided to fix the pool lights at my brother in laws cottage 'way' up
> north and talked to a pool tech before going.
>
> He stated the power transformers were the weak point.
>
> This fiber unit used a 12 V 75W 'pot light' and a colored spinning wheel
> but supposedly could take a 100W.
>
> Sure enough, I didn't even need to meter the power supply once I saw the
> melted solder on the output transistors. A new unit was pricey and I
> 'really' don't like replacing 'weak points' with 'new' weak points.
>
> So I went into the local town to the hardware store, picked up a 120V 50W
> bulb (the biggest they had, no 75's), went across the street to a Radio
> Shack and found a couple pigtails that fit the bulb's base because no one
> had the proper pigtail in town and converted the sucker to a 'line
> voltage' box.
>
> Basically I tossed out the 12 volt crap and just went 120V. It works
> great and some day when I go back up if I get ambitious I will up the bulb
> to a 75W or even the 100W the 'fixture' says it can handle. There is a
> colored wheel to avoid melting.
>


I did the same thing, I bought a pack of 120v/50w bulbs and did a test run
with them. they are not bright enough.

It turns out that I don't know how to use my own volt meter (the one I built
20+ years ago from a kit). Crap! I hate when that happens.

The bulb is toast and the transformer is fine. I order new lamps and
reinstalled the transformer.




"Jeff Strickland" > wrote in message
news:6R27i.2970$J76.2363@trndny03...
>I thought I knew this stuff, but there is a nuance that I'm not getting.
>
> I have a fiber optic lighting system in my swimming pool. It takes a
> 24v/250A light bulb. The bubl does not light, but the filiment is okay.
> The power supply (transformer) does not put out any voltage, so I bought a
> new one.
>
> The new transformer is stated to provide 40VA, but the light does not come
> on. My guess is that a VA and a "regular" A are different. What's the
> difference?
>
>
>
>
>
>
>

"mack" > wrote in message
...
>
> After all this back-and-forth about the problem, all I can add is that
> Jeff
> ought to not throw good money after bad, or incur further risk to himself
> by
> calling in a really good electrician (not the guy who can replace a wall
> switch) and leave it to him. We all think we know a little about
> electricity, and it's just enough to get a surprise in the form of a
> lethal or nearly lethal shock.

A nearly lethal shock will give you years and years of health problems, as
any survivor of being struck by lightning can tell you.

I have a garage that was wired without a single junction box, except where
required for switches and receptacles. The cables are just spliced together
in the middle of the air. A piece of extension cord material was used to
feed one room. It was of course wire nutted into a piece of romex and then
sealed into a wall. I lost no time in telling the seller of the property
and the guy who wired the garage that both were morons.

Either get a real electrician or a Time/Life diy book.

> I'd just as soon not read the news and find that Jeff Strickland was found
> face down with two wires in his hands. ....."let's see now, was that 250
> Amps or 250 Watts???"
> Stick to plumbing repairs. Lots of professional electricians have
> succumbed to electrical shock, but I've yet to hear of a plumber drowning.
>
There is an electric pipe thawer that could give you quite a jolt. I see a
lot of burned fingers from sweating copper tubing together.

Saludos cordiales,

Earle

"mack" > wrote in message
...
>
> After all this back-and-forth about the problem, all I can add is that
> Jeff ought to not throw good money after bad, or incur further risk to
> himself by calling in a really good electrician (not the guy who can
> replace a wall switch) and leave it to him. We all think we know a
> little about electricity, and it's just enough to get a surprise in the
> form of a lethal or nearly lethal shock.
> I'd just as soon not read the news and find that Jeff Strickland was found
> face down with two wires in his hands. ....."let's see now, was that 250
> Amps or 250 Watts???"
> Stick to plumbing repairs. Lots of professional electricians have
> succumbed to electrical shock, but I've yet to hear of a plumber drowning.
>


I'm a handyman by trade, and applying Ohm's Law has never ever come up for
me in the past. Had I known the difference between VA and amperage, we would
not be having this discussion. I've added complete new circuits from the
fuse panel, replacing a light bulb ought to be a job I can handle. Having
said that, I did find it exceedingly difficult to get the correct
information from my meter, and I's still not sure if it was the meter that
was lying, or the idiot-in-charge pushing the wrong buttons.

And you should note that W and A are adjacent to one another on the
keyboard. While there is significant difference in 250A and 250W, the
keystrokes are nearly identical.

"Earle Horton" > wrote:

> Either get a real electrician or a Time/Life diy book.

The diy book might be safer, a good friend recently retired from his
job as a building inspector, he was a journeyman electrician by trade
before becoming an inspector so he knew the electrical code very well.

He said it was almost unbelievable the number of jobs done by
experienced, licensed, electrical contractors and/or electricians that
had to be ripped out and done over because of numerous code violations
and unsafe wiring done intentionally to save a buck.

You'd think it would be cheaper to wire a building correctly than to
tear it all out and do it over but the contractors lived with the
constant hope they wouldn't get caught... :-(


--
XS11E, Killing all posts from Google Groups
The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html

Jeff Strickland wrote:
>
> "Mike Romain" > wrote in message
> g.com...
>> Jeff Strickland wrote:
>>> I thought I knew this stuff, but there is a nuance that I'm not getting.
>>>
>>> I have a fiber optic lighting system in my swimming pool. It takes a
>>> 24v/250A light bulb. The bubl does not light, but the filiment is
>>> okay. The power supply (transformer) does not put out any voltage, so
>>> I bought a new one.
>>>
>>> The new transformer is stated to provide 40VA, but the light does not
>>> come on. My guess is that a VA and a "regular" A are different.
>>> What's the difference?
>>>
>>
>> Just another thought for you.
>>
>> I decided to fix the pool lights at my brother in laws cottage 'way'
>> up north and talked to a pool tech before going.
>>
>> He stated the power transformers were the weak point.
>>
>> This fiber unit used a 12 V 75W 'pot light' and a colored spinning
>> wheel but supposedly could take a 100W.
>>
>> Sure enough, I didn't even need to meter the power supply once I saw
>> the melted solder on the output transistors. A new unit was pricey
>> and I 'really' don't like replacing 'weak points' with 'new' weak points.
>>
>> So I went into the local town to the hardware store, picked up a 120V
>> 50W bulb (the biggest they had, no 75's), went across the street to a
>> Radio Shack and found a couple pigtails that fit the bulb's base
>> because no one had the proper pigtail in town and converted the sucker
>> to a 'line voltage' box.
>>
>> Basically I tossed out the 12 volt crap and just went 120V. It works
>> great and some day when I go back up if I get ambitious I will up the
>> bulb to a 75W or even the 100W the 'fixture' says it can handle.
>> There is a colored wheel to avoid melting.
>>
>
>
> I did the same thing, I bought a pack of 120v/50w bulbs and did a test
> run with them. they are not bright enough.
>

Is that as big as they make for that size I wonder?

I really like the brighter lights because they do a wicked show in a
snowstorm when sitting in the hot tub.

I think if I could get one without the diffuser lens on it all the light
would be in a spot on the fiber end. In my case I am only talking a
25-50W difference, not a couple hundred like yours...

I was almost thinking on cutting the diffuser off one just to see.

I also have worked on pools in various sizes since the 70's and have a
good working knowledge of the power setups so swapping over to a line
voltage light was easy.

Mike