mains light bulb tester.

[bryantramos79]

I have used the search tool and found thousands of threads and posts with the words "Mains light bulb tester", but no luck finding a post with instructions on how to make and use it.

 

[jerryo]

Hi,
try a site called "Decibel Dungeon"; if I remember correctly there are full instructions on the site. Very interesting site, so well worth a look at anyway.

 

[luka]

??

I don't get this... why not just connect it to mains and see if it works?

 

[thevoice]

I spent ten years as a professional lighting tech and never found a need for such a thing...

 

[Mooly]

I have used the search tool and found thousands of threads and posts with the words "Mains light bulb tester", but no luck finding a post with instructions on how to make and use it.

I assume you mean a light bulb tester to prevent damage to amps etc during fault finding

If so it's just a 60 or 100 watt mains filament bulb wired in series with the mains to the appliance.
If there is a fault, the bulb lights rather than blowing a load of semiconductors.

Perhaps "inrush current limiter" would be a better choice of words.

 

[bryantramos79]

@ jerryo, decibeldungeon is a helpful site, i'll have to do some more searching. @ Mooly, "I assume you mean a light bulb tester to prevent damage to amps etc during fault finding". Yes sir that's what i meant. I was gathering information about transformer wiring options and grounding techniques, and the bulb tester kept on showing up in the threads. That's what got me thinking i should build one for myself. Thanks for the help guys.

 

[Kinnja]

I haven't built one yet, but I expect to soon. I think one important issue is that the load--your amp for example, be in series with the bulb, not parallel.

I think the way the schematic at Decibel Dungeon is drawn can be a little confusing.

Check these two links:

The Dim-bulb Radio Tester

Dim Bulb Tester

 

[bob91343]

The poor man's variac I guess. I have used variable autotransformers for years and they are the best solution, but new ones today are ridiculously expensive.

 

[Enzo]

Enter "light bulb limiter" into google. You will get several links to instructions for building this extremely simple device on the first page of hits.

It is no more complex that inserting an incandescent light bulb in series with the equipment you are servicing. In its simplest form, a lamp socket with two clip wires coming from it, clipped in place of the mains fuse in the gear under test.

 

[bryantramos79]

thanks

Kinnja, two very helpful links thank you. And Enzo , i don't know why i didn't think to google it , thanks for the help, i appreciate the effort guys.

 

[AndrewT]

I spent ten years as a professional lighting tech and never found a need for such a thing...

and I am sure there are millions of other professionals in the electronics/electrical field that don't need one either.
They will all know how to safely wire up a twin primary transformer so that the windings are in phase and thus avoid a dead short across the mains supply.

It's us amateurs that need protecting from ourselves!

 

[Enzo]

Andrew, I think his point was that as a lighting person he didn't need something to test light bulbs.

You see? "light bulb tester" can be taken to mean a tester that uses light bulbs ( what we meant) or a tester OF light bulbs, (which we did not.).

 

[thevoice]

Yes, I took it to be a tester of lightbulbs. An odd thing to need.

I'm familiar with using a lightbulb in line with a device under test, but I hadn't heard it refered to as a lightbulb tester, or at least it didn't occur to me.

 

[Enzo]

I built a fuse tester once. If the fuse flashed, that meant it had been good.

 

[Speedskater]

Se the following schematic:

 

[sandbasser]

Here's a couple of links:

The Dim-bulb Radio Tester

Building a Gainclone chip amp power supply.

IMHO the "Decibel Dungeon" site is an excellent resource.

Both are essentially the same as Speedskater's schematic.

Regards,

 

[Steve Dunlap]

The poor man's variac I guess. I have used variable autotransformers for years and they are the best solution, but new ones today are ridiculously expensive.

Some amps will not power up on a variac without risk of damage. The light bulb prevents this.