| (19) |
 |
|
(11) |
EP 0 991 042 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
10.01.2001 Bulletin 2001/02 |
| (43) |
Date of publication A2: |
|
05.04.2000 Bulletin 2000/14 |
| (22) |
Date of filing: 21.09.1999 |
|
| (51) |
International Patent Classification (IPC)7: G08B 29/06 |
|
| (84) |
Designated Contracting States: |
|
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
28.09.1998 GB 9821059
|
| (71) |
Applicant: APOLLO FIRE DETECTORS LIMITED |
|
Havant Hampshire P09 1JR (GB) |
|
| (72) |
Inventor: |
|
- Payne, Roger Dennis
Havant, Hampshire PO9 1JH (GB)
|
| (74) |
Representative: Cozens, Paul Dennis et al |
|
Mathys & Squire 100 Grays Inn Road
London WC1X 8AL
London WC1X 8AL (GB) |
|
| |
|
| (54) |
Signalling device and monitoring system |
(57) A signalling device, such as a fire detecting device, has a head (2) which is removable
from a base (1). The head has circuit means (4,5,6) for sensing and signalling a change
in given condition. The base is connected to supply lines and has fault signalling
means (3) for generating a fault signal due to head removal or some other device fault.
As the same signal is generated in each case, the invention provides an economic,
simple and reliable solution to the problem of signalling fault conditions. Preferably,
the fault signalling means includes a first circuit (3) in the base (1) which responds
to an output from a second circuit (7) in the head (2) so that, if the head is not
fitted to the base, the first circuit (3) responds to the absence of said output from
the second circuit (7) in order to apply the fault signal to the lines.