Oldham BM25, User Manual

Page: 35 / 80

4
– Wireless Version
35
Chapter 4
| Wireless Version
This product complies with FCC Maximum Permissible Exposure (MPE)
requirements when used with an approved antenna and the antenna is at
least 20 cm away from the user. Use of the product closer than 20 cm may
exceed the MPE limits. Use of any antenna other than approved antennas
will invalidate the certification of the product.
Overview
Available as an option, the radio communication allows
several BM 25Ws to communicate on the same network (
BM
25 mode) or to send information wirelessly to a MX40 or X40
controller (CONTROLLER mode).
Wireless communication is made via a 2.4 GHz radio and
emitted power is less than 100 mW. Maximum distance
between two communicating devices is 3,300 feet line of
sight. Up to 30 BM 25Ws can be meshed on the same
network and up to 16 networks can coexist with no
interference.
The network topology used by the BM 25W is a MESH
network. In a mesh network all hosts are connected peer to
peer without central hierarchy, thereby forming a net-like
structure. Consequently, each node can receive, send and
relay data. This avoids having sensitive points, which in case
of failure, cut the connection of the network. If a node is
down, its neighbors go through another route.
Mesh topology allows fast and simple deployment, high
coverage versatility and high fault tolerance. It significantly
reduces installation and operating costs of networks. These
solutions reproduce the architecture of the Internet while
optimizing for wireless.
Figure 20 : Wireless
version, recognizable
by the presence of an
antenna
BM 25 Mode
When in BM 25 mode, BM 25Ws send information regarding gas alarm and fault
status. Once a BM 25W is in gas alarm, the alarm is repeated on all other BM 25Ws on
the same network.