On Thursday, May 7, 2015 at 10:34:07 PM UTC+1, Capitol wrote:
Another John wrote:
I've said this before in a similar thread a few months (a year?) ago:

- I paid about 800 for our electric, remote controlled roller door,
fitted by "a bloke who works at the factory where they make them".

- It's a cheap door, but we have been delighted with it (WONDERFUL
compared to the extremely heavy, draughty, up'n'over that it replaced.
However ...

- ... the only safety mechanism to prevent it relentlessly closing on an
obstruction is a 'magic eye'. This work fine for cars, people --
anything bulky; but if you have left (say) a spade propped in the
doorway, it won't see it. It will close, and it will snap its flimsy
plastic clamps, which secure it to the roller. It is a big and fairly
skilled job to replace these.

- Thanks to breaking the clamps TWICE, I have developed an intensely
ingrained habit of watching the door close. This habit is still not 100%
good enough -- I closed the door on a shallow box only last week --
missed by the magic eye, and also by my own eye: a horrible crunching
ensued, but I *think* I may have got away with it as Basil said.

- Next time I get such a door installed I will splash more money and get
one with e pressure detector across the whole bottom edge, which will
stop, and reverse, the mechanism as soon as anything is touched: that is
the proper way to do it (I now know :-( ).

John

Up and over motorised doors sense the closing force and reverse when a
current limit is exceeded. I don't know if roller doors have this function.

Yes, In our door it can be adjusted easily. If not set correct the door will give false stop and returns or keep trying to go through he floor for a few seconds.