Hi all,

I have just added an IR beam across the path of the door, for an extra bit
of people/animal safety and to let me know when the tail end of my car is
just clear of the door. One of these - Ebay item 170185660628.

It should work with pretty well any system, as it works on ac/dc 12v to
240v, making or breaking a relay when the beam is interrupted over a maximum
door width of up to 5m using a reflector at the far end from the sensor -
and about half the price of some of them.

I set it at the same height as my cars tow ball, so I can watch its LED as a
means to confirm when the car is clear of the door -which is as near as
matters the advised mounting height for such things anyway.

I have BTW in the recent wet weather found a minor disadvantage with roller
doors v canopy panel type doors - if the door is wet when it is opened, they
drip incessantly once rolled up inside the garage. I also notice a quite
wide and drafty gap along the width of the top of the door just below the
powered roller - between door and the surface the roller is mounted upon. I
have just gone to some trouble to seal up some of the other drafts, so I'll
need to look at finding an effective way to seal this one too. Not much
point in a well sealed and insulated roller door, if it leaks drafts all the
way along the top, is there?

--
Regards,
Harry (M1BYT)

On 2008-01-15 20:30:16 +0000, "Harry Bloomfield"
said:

Hi all,

I have just added an IR beam across the path of the door, for an extra bit
of people/animal safety and to let me know when the tail end of my car is
just clear of the door. One of these - Ebay item 170185660628.

It should work with pretty well any system, as it works on ac/dc 12v to
240v, making or breaking a relay when the beam is interrupted over a maximum
door width of up to 5m using a reflector at the far end from the sensor -
and about half the price of some of them.

I set it at the same height as my cars tow ball, so I can watch its LED as a
means to confirm when the car is clear of the door -which is as near as
matters the advised mounting height for such things anyway.


I believe that there is a safety standard around all of this which I
thought was meant to be applied to all new powered garage doors.

Mine has one sensor beam fitted to the door frame I guess about 500mm
up from the floor. This is intended to catch items in the way before
the door closes or animals or small kids running through as the door is
closing.

The other is a beam fitted to the door itself. This is intended to pick
up objects higher up such as adults and cars.

At any rate, one thing to think about, if doing this as a DY project,
is how the logic interlocks work.

The tricky case is one where the door is closed and a box etc. stored
inside tips over and blocks the beam. Simple logic will prevent the
motor from operating. However, if there isn't a manual means to open
the door, or a pedestrian door to the garage, then one can be class F.