What is the purpose of the riveted tabs on these downlighters

[Milleniumaire]

Can anyone explain the purpose of the riveted tabs on the Enlite EN-DLM981X downlight as shown in these photos?

20190707_152004

• Milleniumaire
• 7 Jul 2019

20190707_152016

• Milleniumaire
• 7 Jul 2019

These fittings require a 75mm hole to be drilled, which is slightly wider than the body of the downlight, however these tabs near the facing end of the light fitting will dig into the 12mm thick plasterboard. I'm struggling to understand the purpose of these, other than to damage the plasterboard and make it more difficult to push the light fittings into place. I can only assume they are meant to stop the light fitting "twisting" and possibly to hold it more securely, but why, when they have two powerful spring loaded anchors? It also means it is necessary to be very careful about what direction the fitting is installed as once pushed into the hole, it can't be turned.

 

[securespark]

Have you asked Enlite?

 

[Milleniumaire]

If I had asked Enlite, I wouldn't be posting the question on this forum!

Besides, it's Sunday.

Thought I would ask the experienced guys on diynot as their purpose may be obvious to people who install downlights regularly and therefore deal with lots of different makes and models.

 

[Tigercubrider]

Aren't they meant to bend as you insert the downlighter from below? Then spring back?
They'd stop a down lighter dropping back out

 

[Milleniumaire]

Hi Tigercubrider, they do have a little bit of flex in them, but not much, so I'm sure as the light fitting is pushed up into the ceiling they will be bent into the light fitting body, but as they are wider than the 75mm diameter hole, they will still result in the plasterboard being crushed/damaged as they are pushed up. They won't spring back however because they will be lodged into the plasterboard i.e. they aren't high enough up the body of the fitting to be pushed into the ceiling void. I would have thought the spring loaded clips would be sufficient to prevent the fitting from dropping back out.

 

[EFLImpudence]

I don't know. I used to snap them off - to prevent the damage for the reasons you state.

 

[Milleniumaire]

I don't know. I used to snap them off - to prevent the damage for the reasons you state.

Interesting. That also crossed my mind! However, as they are fire rated, I'm not sure they should be modified. I suspect the tabs will give a more tight fitting, which is what might be necessary to achieve the required fire rating.

 

[Notch7]

Id guess they are there to centralise the downlighter in the plasterboard hole.

 

[Milleniumaire]

Because this particular fitting is fire rated, the bezel is separate and incorporates a glass cover and a rubber/silicone seal and it screws into the fitting after the fitting has been fixed to the ceiling. I suspect therefore these tabs are meant to give the body of the fitting more purchase so when the bezel is screwed on, it gives a good tight seal and doesn't "pull" the fitting down from the ceiling, which might happen if only the spring loaded anchors were used to hold the fitting in place.