• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Dim Bulb Tester Question!

reardonp6

reardonp6

Hot Ruddered Bum
Subscriber
I just built a dim bulb tester, I'm pretty sure I hooked everything up correctly, my question is how do I test it, without a shorted piece of equipment? I'm using a 60 w bulb, it does not burn brightly when somthing is pluged in, that is good, however it does not dim which it should do without a short! When I turn on the tester, with the amp luged in, the amp comes on, just no dimming of the test lamp. Thanks for your help!
 
Register to hide this ad
How powerful is the equipment? Sometimes they act that way. Put a different bulb in, try a 100W'r. If something was terribly wrong the bulb would be bright.

Barney
 
Oerets said:
How powerful is the equipment? Sometimes they act that way. Put a different bulb in, try a 100W'r. If something was terribly wrong the bulb would be bright.

Barney
Click to expand...
I tried a 100 watt bulb, still no dim glow! I will try a different piece of equipment and
see if I get any results. Thanks for your input.
 
Typically you would see the bright to dim of the DBT because of initial inrush current while filter caps charge with an amplifier for example. The dimming or another way to put it, brightness of the DBT bulb, depends on the wattage size and the DUT. You could have an amp that is operating perfectly normal with a 100W as your DBT but the bulb is glowing. This isn't indicative of a short or problem but just that it's drawing enough current to light the bulb more or less depending on well, the CURRENT DRAW. Now if the DBT is BRIGHT while testing something means your choking an otherwise properly operating piece of equipment too much i.e DBT bulb wattage to small or there IS excessive current draw from the device.

Here is a neat "trick" you can use in order to test the function of your DBT. In order to test your DBT use TWO bulbs of the SAME wattage. For example, plug a 40W, 60W or 100W bulb in to the DBT and use the same wattage bulb in a regular lamp for your DUT. You will find that both lamps will "share" the current and light up equally. This will confirm that your DBT is working correctly. Here are some easy visualization experiments and to get an idea of the current relationship between the DBT and DUT. Try a 100W bulb in the DUT lamp with a 40W or 60W in the DBT. The DBT bulb will light up bright and you'll likely see a very faint glow from the 100W DUT lamp with a 40W and a bit more of a glow with a 60W. Now if you were to reverse things with either a 40W or 60W as the DUT with the 100W in the DBT the same effect results but the DUT lamp will light brightly with a faint glow from the 100W DBT.
 
OverLoad said:
Here is a neat "trick" you can use in order to test the function of your DBT. In order to test your DBT use TWO bulbs of the SAME wattage. For example, plug a 40W, 60W or 100W bulb in to the DBT and use the same wattage bulb in a regular lamp for your DUT. You will find that both lamps will "share" the current and light up equally. This will confirm that your DBT is working correctly. Here are some easy visualization experiments and to get an idea of the current relationship between the DBT and DUT. Try a 100W bulb in the DUT lamp with a 40W or 60W in the DBT. The DBT bulb will light up bright and you'll likely see a very faint glow from the 100W DUT lamp with a 40W and a bit more of a glow with a 60W. Now if you were to reverse things with either a 40W or 60W as the DUT with the 100W in the DBT the same effect results but the DUT lamp will light brightly with a faint glow from the 100W DBT.
Click to expand...

Nice idea. :thmbsp:
 
maybe you wired it wrong ...try plugging something in without the lamp in circuit and see what happens .
 
petehall347 said:
maybe you wired it wrong ...try plugging something in without the lamp in circuit and see what happens .
Click to expand...
Perhaps a little elaboration is in order :)

If things are wired properly one would expect that the DUT will not get any power whatsoever with the DBT bulb removed. If there is power to the DUT with the DBT bulb removed then there's some wiring issues.
 
OverLoad said:
Perhaps a little elaboration is in order :)

If things are wired properly one would expect that the DUT will not get any power whatsoever with the DBT bulb removed. If there is power to the DUT with the DBT bulb removed then there's some wiring issues.
Click to expand...

Unless he wired the HOT and Neutral leads to the bulb and jumped off the light to the receptacle. Just to make sure of your wiring, HOT to the bulb on one lug, HOT out of the bulb to the Hot on the receptacle. Neutral straight to the receptacle.
 
Last edited:
Yup, that's certainly a possibility.

Edit: I'd prefer things be referred to correctly as HOT and NEUTRAL, not common and positive.
 
Last edited:
Silverman said:
Unless he wired the HOT and Neutral leads to the bulb and jumped off the light to the receptacle. Just to make sure of your wiring, HOT to the bulb on one lug, HOT out of the bulb to the Hot on the receptacle. Neutral straight to the receptacle.
Click to expand...
If I'm understanding what you are describing here, then the lamp socket would simply be in parallel with the DUT receptacle and the DUT would still get power whether the bulb is inserted or not.
 
petehall347 said:
we have live and neutral here ...some places have hot and cold .. i understand both .
Click to expand...
Hot and live would be acceptable. I also understood positive and common as what was original referred to here but when you find that as proper anywhere in the world with respect to AC please do let me know.
 
OverLoad said:
If I'm understanding what you are describing here, then the lamp socket would simply be in parallel with the DUT receptacle and the DUT would still get power whether the bulb is inserted or not.
Click to expand...

Yes that is what I am describing. I am not the best at getting what is in my brain on paper in a clear message. I think it the age factor.:scratch2:

The dim bulb receptacle should not have any power to it if the bulb is removed.
 
You must log in or register to reply here.
Back
Top Bottom