3.4 Transmission Range
The main factors that influence the system transmission range are:
o
Type and location of the antennas of receiver and transmitter
o
Type of terrain and degree of obstruction of the link path
o
Sources of interference affecting the receiver
o
“Dead” spots caused by signal reflections from nearby conductive objects
Since the expected transmission range strongly depends on these system conditions, range
tests should categorically be performed in early project phases!
The following figures for expected transmission range are considered by using a PTM, or STM
transmitter device and the RCM radio receiver device with preinstalled whip antenna and may
be used as a rough guide only:
•
Line-of-sight connections:
Typically 30m range in corridors, up to 100m in halls
•
Plasterboard walls / dry wood:
Typically 30m range, through max. 5 walls
•
Brick walls / aerated concrete:
Typically 20m range, through max. 3 walls
•
Ferroconcrete walls / ceilings:
Typically 10m range, through max. 1 ceiling
•
Fire-safety walls, elevator shafts, staircases and supply areas should be
considered as screening
.
The angle at which the transmitted signal hits the wall is very important. The effective wall
thickness – and with it the signal attenuation – varies according to this angle. Signals should
be transmitted as directly as possible through the wall. Wall niches should be avoided. Other
factors restricting transmission range:
•
Switch mounted on metal surfaces (up to 60% loss of transmission range)
•
Hollow lightweight walls filled with insulating wool on metal foil
•
False ceilings with panels of metal or carbon fiber
•
Lead glass or glass with metal coating, steel furniture
The distance between EnOcean receivers and other transmitting devices such as computers,
audio and video equipment that also emit high-frequency signals should be at least 1m.
A summarized application note to determine the transmission range within buildings is
available as download from
www.enocean.com
.
©EnOcean GmbH, W. Heller
Page 16 of 19
PTM 200C User Manual V1.01
