JUMO Wtrans T03, Operating Manual

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4 Transmitter range
32
4.2 Impairment of wireless transmission
Collisions when using too many transmitters
When using a large number of transmitters, do not select a transmission interval which is too low as oth-
erwise the radio frequency will be unnecessarily occupied. A transmission interval that is too low leads
to a very high data volume on the selected frequency, which can lead to collisions with other transmitters.
The collisions can cause telegrams to be destroyed during wireless transmission.
Fig. 4-1 The telegrams of a transmitter reach the receiver without collisions
Fig. 4-2 The telegrams of several transmitters can collide
External transmitters
The radio frequency is also available to other users. External transmitters can transmit on the same fre-
quency. If, for example, the transmitter and an external transmitter transmit their radio telegrams at the
same time, the telegram will be destroyed. No error is detected because the transmitters cannot check
their own transmission while transmitting.
Electrical devices
In a harsh industrial environment, wireless telegrams can be destroyed by such things as frequency con-
verters, electrical welding equipment, poorly shielded PCs, audio/video devices, electronic transformers,
electronic ballasts, etc.
Radio telegram
ID, measuring
value
Receiver Transmitter
Radio telegrams Transmitters
ID, measuring
value
ID, measuring
value
ID, measuring
value
ID, measuring
value
ID, measuring
value
Receiver