Tube light problem

[Homesafe]

Hi, As above I have a problem with my tube light, I changed it recently cos the old one apparently stopped working so I went and bought a new one and also changed the starter too.
I believe you have to change the starter every time you get a new tube , maybe I'm wrong.
Anyway the tube now has started to have problems coming on and when it does come on then it starts going on and off every few secs randomly.
However when I turn the starter round and the light comes on it stays on regardless even if the starter is taken out.
When it is switched off tho it doesnt switch back on obviously cos theres no starter.
Help!!
It did all the above with 2 starters so that eliminates them.( I think)

 

[mfarrow]

If the light stays on with the starter turned round why not leave it that way?

A starter is just that, a starter. It's not required for continued functioning. It's not uncommon to hear of tight-fisted people taking a single starter around a room to start lamps individually when they've only one working one left!

It sounds like the unit, the ballast, might be on it's way out. Either swap the fitting or try an electronic starter. These are usually green.

 

[Lectrician]

Sounds like a faulty or under rated starter to me!

 

[viewer]

I think the OP means that moving the starter makes it work. As two known to be good starters give same effect maybe the connections inside the lamp are loose or the starter holder is badly made. Does the starter wiggle in its socket? You could either take the lamp back (best) or use the starter holder from the old lamp.

 

[ericmark]

I would guess wrong size tube but also could be wrong type of starter. This is common with ageing tubes also.

On the ballast there will be tube size written I have seen where a thin tube has been fitted instead of the original thicker one for this to happen. A 1500mm or 5 foot tube can be 65W (T12 38mm dia) or 58W (T8 26mm dia) both fit but using wrong one will cause this fault.

 

[ekmdgrf]

I would connect a small motor to the starter and power it off the light. When you switch the light on, the motor rotates the starter and the lights comes on.

 

[viewer]

Sorry, misread; thought the whole unit had been changed.

 

[Homesafe]

It could be wrong starter, the tube is new but as the one taken out is starting to go dark on one end ( the old one wwas dark at both ends, )which usually indicates a knacked tube or summat doesnt it?

 

[winston1]

I believe you have to change the starter every time you get a new tube , maybe I'm wrong.

Wrong, there is no need to change the starter when you get a new tube. Maybe your new starter is the wrong type. Try the original old starter.

 

[333rocky333]

check the wattage of the lamp is compatible with the wattage stamped on your starters.

 

[Homesafe]

Thanks guys, I will check the tube v the stoarter first, why does the tube get darker at the ends?

 

[Lectrician]

I believe you have to change the starter every time you get a new tube , maybe I'm wrong.

Wrong, there is no need to change the starter when you get a new tube. Maybe your new starter is the wrong type. Try the original old starter.

In commercial applications, it is always best to change both.

A faulty lamp, left on for a sustained period will age the starter considerably.
A faulty starter, left on for a sustained period will age the tube considerably.

Always change them as a pair.

 

[bernardgreen]

why does the tube get darker at the ends?

Most common reason is the phospher coating being burnt by the heaters being on for too long due to the starter not operating correctly.

When switched on the starter is closed and current flows through the heaters ( filaments at each end of the tube ) in series. The heat makes the gas in the tube more conductive and thus easier to strike. Once the tube has struck the start ( should ) open and the current through the heaters ceases.

Another reason is the current through the tube is too high

The current through the tube also flows along the heaters and with excessive current they can remain hot enough to scorch the phospher over long period of time. Often caused by a faulty ballast.

 

[winston1]

I believe you have to change the starter every time you get a new tube , maybe I'm wrong.

Wrong, there is no need to change the starter when you get a new tube. Maybe your new starter is the wrong type. Try the original old starter.

In commercial applications, it is always best to change both.

A faulty lamp, left on for a sustained period will age the starter considerably.
A faulty starter, left on for a sustained period will age the tube considerably.

Always change them as a pair.

Faulty lamps or starters should not be left on for sustained periods. In the various commercial premises I have worked in throughout my career I have never seen a sparks change a starter when the tube was changed.
Anyway the OP is not a commercial premise and it appears changing the starter has caught him out as I suspect he has replaced a good one with the wrong type.

 

[JohnW2]

In the various commercial premises I have worked in throughout my career I have never seen a sparks change a starter when the tube was changed.

I cannot argue with that but, FWIW, I've always changed starters when I've changed tubes in my residential installations.

Of course, it could be argued that, unless (s)he is instructed by customer to also change the starter, it's not in an electrician's interest to do so. If they don't change the starter, there is the prospect of another call-out fee to change the starter, and perhaps a call-out fee a bit sooner if a non-changed starter results the new tube's life being reduced.

Given that starters cost so little (in comparison with other costs) it would seem pretty sensible for the customer to instruct the electrician to change starter as well as tube, for the converse of the reasons that it might not be in the electrician's interest to do that!

Kind Regards, John