Fluorescent pins

Thread Starter

xchcui

Joined May 12, 2014
227
T-8-Fluorescent-Bulbs-387-IAPcrs.jpg




Hi.

As far as i know,the tips of the pins are usually sealed by a kind of solder.
Recently,i bought several fluorescent bulbs,that most of their tips were
opened(missing that solder,so i could see the other side,if i looked through the opened pins).
May this condition interfere with the fluorescent bulb operation or reduced
its life?I was even surprised that it turned-on at all.:confused:Thanks.
 

MrSalts

Joined Apr 2, 2020
2,043
View attachment 272120




Hi.

As far as i know,the tips of the pins are usually sealed by a kind of solder.
Recently,i bought several fluorescent bulbs,that most of their tips were
opened(missing that solder,so i could see the other side,if i looked through the opened pins).
May this condition interfere with the fluorescent bulb operation or reduced
its life?I was even surprised that it turned-on at all.:confused:Thanks.
The sealing is done with an alloy that matches the thermal expansion of the glass - otherwise the glass will crack when it shrinks on cooling.
If it is an LED-replacement bulb (non-fluorescent bulb), it will not be sealed. Also, the temp at those terminals will likely get too hot to avoid melting solder.
 

MisterBill2

Joined Jan 23, 2018
12,690
I have NEVER come across a florescent lamp tube with the end pins embedded in the glass. Always wires from the elements are sealed in the glass and then most often crimped into the pins, because it is much cheaper than soldering.
The tube in the photo certainly has the pins crimped on the wires, no question about that. The LED tubes usually have the wires crimped, but not always.
 

Thread Starter

xchcui

Joined May 12, 2014
227
Thanks for your answers.
The photo that i attached was taking from the web.It was just to show what pins i was talking about.As your answers were based on this photo,i guess that i made a mistake when i uploaded it.
So i upload again the original photos of one of my fluorescent pins,both sides:
WhatsApp Image 2022-07-26 at 14.16.41.jpegWhatsApp Image 2022-07-26 at 14.13.28.jpeg





As you may see,the tips(edges)of the pins are not completely sealed.(crimp?)Shouldn't the tips of the pins be sealed?
Can't the gas escape out from this,not sealed,pins?
 
Last edited:

Ya’akov

Joined Jan 27, 2019
6,260
Thanks for your answers.
The photo that i attached was taking from the web.It was just to show what pins i was talking about.As your answers were based on this photo,i guess that i made a mistake when i uploaded it.
So i upload again the original photos of one of my fluorescent pins,both sides:
View attachment 272232View attachment 272231





As you may see,the tips of the pins are not completely sealed.(crimp?)Shouldn't the tips of the pins be sealed?
Can't the gas escape out from this,not sealed,pins?
Those pins are not open to the inside of the tube. In some designs, the pins have wires that come from the tube inserted in them and them soldered in place from the end. This design uses a different method of electrically connecting them. It has no effect on operation or lifetime.

[EDIT: fixed confusing punctuation and changed the dude back into a tube as it was meant to be.]
 
Last edited:

MisterBill2

Joined Jan 23, 2018
12,690
If the the has stopped working then you can measure the resistance between the pins, it should be just a few hundred ohms or less. If it is an open circuit and the pins do not appear to be crimped onto the wires then soldering the pin inside might fix the tube, if a poor connection is the problem. But usually that is not the point of failure for tubes.
 

Thread Starter

xchcui

Joined May 12, 2014
227
If the the has stopped working then you can measure the resistance between the pins, it should be just a few hundred ohms or less. If it is an open circuit and the pins do not appear to be crimped onto the wires then soldering the pin inside might fix the tube, if a poor connection is the problem. But usually that is not the point of failure for tubes.
The bulbs are new and they are working.I just wasn't sure about
the condition of the pins(as i described before).
I understand,according to Ya'akov explanation,that it has no effect on operation or lifetime.
But if the bulb will flicker within a short time,may it be a poor connection,
as you suggested?
[EDIT: fixed confusing punctuation and changed the dude back into a tube as it was meant to be.]
Ya'akov,may you explain your last edit?i didn't understand what you meant.
 

Ya’akov

Joined Jan 27, 2019
6,260
The bulbs are new and they are working.I just wasn't sure about
the condition of the pins(as i described before).
I understand,according to Ya'akov explanation,that it has no effect on operation or lifetime.
But if the bulb will flicker within a short time,may it be a poor connection,
as you suggested?

Ya'akov,may you explain your last edit?i didn't understand what you meant.
The edit was to the post, the message in brackets was an explanation. The word "tube" had been autocorrected to "dude", I fixed it and some punctuation.
 

Thread Starter

xchcui

Joined May 12, 2014
227
The edit was to the post, the message in brackets was an explanation. The word "tube" had been autocorrected to "dude", I fixed it and some punctuation.
Okay,i understand.For some reason,i missed the fact that your sentence was written in past tense,so it made me think,mistakenly,that you referred to a problem with my post.:oops:
Thanks for your help.:)
 
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