Specifications

RADIOLINK
Frequently Asked Questions
15
Technically, up to 30 alarms can be interconnected but the limiting
factor is likely to be due to distance between alarms and obstructions
that may block the radio signal. In most domestic properties a realistic
maximum number of alarms would be 12.
A fixed wall switch, Ei411H, is available. This allows Test, Hush and Locate
features to be incorporated into a RadioLINK system without having to
reach up to the smoke alarms. The switch is the same size as a normal
light switch and is powered by a Lithium cell having a realistic 10 year
life. This means that the switch is easily installed, as it does not require
any wiring, the signals to the alarms being transmitted by a radio link.
A Manual Call Point, Ei407, is available for use in larger installations.
This also has the benefits of a Lithium cell power supply and no wiring
connection being required.
In applications where a relay is required to signal to other devices the
Ei428 is available; this is mains operated, but has a rechargeable Lithium
cell back-up supply to ensure that it is operational even in a mains
failure. This is an essential requirement when signalling to Warden Call
Systems. The unit is supplied with a cover to enable it is to be sited at
any convenient position within the property.
BS 5839: Pt.6: 2004 recognises the benefits of radio communication in
the note to Clause 15.5 dealing with power supply requirements for
smoke alarms, thus: “This recommendation [for a single final circuit] does
not apply if the form of interconnection is not capable of conducting
current, e.g. if the means of interconnection compromises radio
communication rather than wiring”.
Building Regulations Document B (England & Wales) allows the use of a
radio link between alarms under section 1.21. The Building Regulations in
Scotland and Northern Ireland currently make no reference of a radio link,
but it is considered that the new recommendations of BS 5839: Pt.6: 2004
would be an acceptable means of meeting the requirements of both
documents.
Yes, the individual smoke alarms and RF bases are not electrically
connected so a phase difference will not affect them. The only
connection between the alarms and bases is by a radio signal.
15. How many
alarms can be
interconnected
using
RadioLINK?
16.Is there any
method of
controlling a
RadioLINK
system?
17. BS 5839: Pt.6:
says that all
alarms must be
on one final
circuit. Will
RadioLINK
comply with this?
18. Can the smoke
alarms be
connected on
different
phases of the
mains supply?