Installation and use MR16
13
3 – SYSTEM DESIGN
3.1 WARNINGS FOR CORRECT INSTALLATION
Maximum distance in the connection between two radio sets is determined by the strength and cleanness
of signal from receiving set. A number of factors may either reduce the strength of received signal or
interfere with signal reception. With proper contrivances, these factors can be removed or minimised.
The strength of radio signal is affected either by the absorption of materials the signal is to run through or
by radio waves reflection phenomena. Below table shows how the different materials affect the power of
transmitted radio signal.
Low absorption
Medium absorption
High absorption
Reflection
Wood (e.g. cabinets,
furniture), plastic,
synthetic materials (e.g.
plexiglas), glass, drilled
bricks (e.g. partition
walls).
Water(e.g. aquariums),
integer bricks, marble.
Concrete, bulletproof
windows, metal
structures (e.g.
household appliances,
piping, railings)
Mirrors, metal surfaces
In some cases, the signal may practically extinguish, e.g. inside metal cabinets.
On the contrary, radio signal may be jammed by not sufficiently screened electronic equipment, electric
motors or other devices working in radio frequency.
For radio devices correct installation apply following precautions:
•
position the devices far from sources of electromagnetic noise, such as electric motors, electric panels,
etc.;
•
do not mount the devices on metal surfaces or close to large metal objects, or inside metal structures,
such as metal boxes or cabinets;
•
should chosen position not allow suitable radio communication, try to displace the device to another
position to see if radio communication is improving.
Warning:
always displace peripheral unit (detector, siren, etc.), not radio module.
To position the various devices, comply with following rules:
•
Radio module MR16
:
o
must be mounted close to wired alarm control panel, possibly not on walls made of either concrete
or integer bricks;
o
its position must allow to see warning LEDs easily;
o
its position must as much as possible be a “middle” position with respect to the various radio
devices.
•
Micro contact DC500
:
o
must be placed inside protected premises;
o
the detector must be placed on door or window frame and the magnet must be placed on door or
window frame wing or leaf, as far as possible from pintles or hinges.
