On one of my exterior lights with integral PIR, the plastic lens cover
behind mesh grill on bulkhead has become all brittle; no doubt due to
UV degradation.

Has anyone any ideas what replacement material that's easily
available, (& UV resistant) may enable a repair??

On 1 Feb 2005 01:27:29 -0800, (Gel) wrote:

On one of my exterior lights with integral PIR, the plastic lens cover
behind mesh grill on bulkhead has become all brittle; no doubt due to
UV degradation.

Has anyone any ideas what replacement material that's easily
available, (& UV resistant) may enable a repair??

The cover usually has a moulded pattern that acts as a multi-segment lens, so you would need to
replace with something pretty much identical.

Yes thanks; its actually an outer lens. The unit is a fixed bulkhead
light, with integral PIR at top/set back somewhat, so there is no
movement adjustment.

That has a patterned lens and is OK; this is a white opaque plastic
just above the polycarbonate front cover[in front of lamp], and is
behind a 3" square of mesh.

Its plain white, and I just wondered what common plastic I may have
knocking around would suffice as relacement, as it seems to essentially
be there for waterproofing.

White plastic office folder type materials won't work as not UV
resistant.

Gel wrote:
On one of my exterior lights with integral PIR, the plastic lens
cover
behind mesh grill on bulkhead has become all brittle; no doubt due to
UV degradation.

Has anyone any ideas what replacement material that's easily
available, (& UV resistant) may enable a repair??

Diamond clear tape works, but is non-fresnel so will change the
detection pattern and sensitivity, you'll need to readjust the unit to
work right. You'll find the max detection range much shorter than
originally, so its good for terraced houses, but no use for country
pads with drives.

If the sun shines on it you may also want to add a top strip of brown
tape to keep sun of the detector to maintain sensitivity.

Proper lens would certainly be better, but have never seen them for
sale.


NT

Where would I get that; is it opaque/clear NT??
Tks

Where would you get clear tape??

What is going on here today?

On 1 Feb 2005 01:27:29 -0800, (Gel) strung
together this:

On one of my exterior lights with integral PIR, the plastic lens cover
behind mesh grill on bulkhead has become all brittle; no doubt due to
UV degradation.

Has anyone any ideas what replacement material that's easily
available, (& UV resistant) may enable a repair??

Buy a new PIR, you'll never get it to work again and the chances are
the UV has affected the PIR itself to some degree over the years.
--

SJW
Please reply to group or use 'usenet' in email subject