Vimar 03925, Руководство по установке

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Application information
7. Application information
7.1 Transmission range
The main factors that influence the system transmission range are:
- Type and location of the antennas of receiver and transmitter
- Type of terrain and degree of obstruction of the link path
- Sources of interference affecting the receiver
- “Dead spots” caused by signal reflections from nearby conductive objects.
Since the expected transmission range strongly depends on this system conditions, range tests should always be performed to determine the reliably achievable
range under the given conditions.
The following figures should be treated as a rough guide only:
■
Line-of-sight connections
Typically 10 m range in corridors, up to 30 m in halls
■
Plasterboard walls / dry wood
Typically 10 m range, through max. 2 walls
■
Ferro concrete walls / ceilings
Typically 5 m range, through max. 1 ceiling (depending on thickness)
■
Fire-safety walls, elevator shafts, staircases and similar areas should be considered as shielded
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 include:
- Switch mounting on metal surfaces (up to 30% loss of transmission range)
- Hollow lightweight walls filled with insulating wool on metal foil
- False ceilings with panels of metal or carbon fibre
- Lead glass or glass with metal coating, steel furniture
The distance between the receiver and other transmitting devices such as computers, audio and video equipment that also emit high-frequency signals should be
at least 0.5 m.
Note that interference from other radio equipment operating in the 2.4 GHz band (WiFi routers, smartphones, wireless audio and video systems, etc.) can have major
impact on radio performance.
7.2 Receiver configuration
03925 communicates user actions (rocker push / release) using a sequence of advertising telegrams as described in chapter 3.
In order to maximize the likelihood of reception of these telegrams, it is necessary that the receiver is either permanently in receive mode on the selected radio chan-
nels or – if this is not possible – is in receive mode periodically on one of the chosen radio channels for a certain minimum period of time.
The two key timing parameters for the periodical reception case are the scan interval (time between the start of two consecutive scanning cycles) and the scan dura-
tion (for how long will the receiver scan within each scanning cycle).
03925 transmits the advertising events with a pause interval of 20 ms between two transmissions. The transmission of the advertising event itself requires approxi-
mately 1 ms per radio channel (meaning approximately 3 ms in total when using 3 radio channels) which means that the total time between the start of two advertising
events is approximately 23 ms.
Considering that the receiver might start scanning directly after the start of one transmission, we can therefore determine that it should remain active (scan duration)
for at least 23 ms to check for the start of the next transmission.
Likewise, we need to ensure that the receiver will become active (scan period) no later than right before the beginning of the third advertising event. So the longest
period for which the receiver can be inactive is given by the time from the beginning of the first advertising events until the beginning of the third advertising event,
meaning approximately 46 ms in total.
The likelihood of correct reception obviously increases if more than one of the redundant advertising events is received. It should also be considered that the receiver
is typically scanning on different radio channels. Therefore the theoretical maximum of 46 ms should be significantly reduced to increase the likelihood of correct
reception.
It is therefore recommended to use a setting of 30 ms scan period and 23 ms scan interval for cases where continuous reception is not possible.