Status WRX900 Series, Руководство по эксплуатации

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As you can see in figure 5 the error curve jumps up at the number of 24 probes.
For this reason, we recommend to use a maximum of 16 probes for the smallest
transmission interval of 1 s.
For the factory setting 10 s, a considerably larger number of probes is possible.
Estimation of the maximum number of transmitters
If more than the recommended 16 probes are to be used at a transmission interval
of 1 s, select a higher transmission interval to prevent an increased error quota.
Example:
16 probes at a transmission interval of 1 s = 32 probes at a transmission interval of
2 s
When the number of probes is to be increased additionally, the following
calculation results in the next example:
Example:
16 probes at a transmission interval of 1 s = 48 probes at a transmission interval of
3 s (theoretical)
At a transmission interval of ≥3 s, however, the telegram is transmitted twice. For
this reason, the number of probes to be used is halved.
16 probes at a transmission interval of 1 s = 24 probes at a transmission interval of
3 s (effective)
The identical behavior occurs from a transmission interval of ≥60 s. From this
transmission interval, the telegram is transmitted three times.
External transmitters
External probes can transmit on the same frequency. If, for example, the probe
and an external probe transmit their radio telegrams at the same time, the
telegrams are destroyed. Due to the fact, that the probes are not able to check
their own active transmission, no error is detected.
Electrical devices
In rough industrial environment, radio telegrams can be destroyed, for example,
by frequency converters, electrical welding equipment or poorly shielded PCs,
audio/video devices, electronic transformers, electronic ballasts, etc.
Error map-out
The radio transmission timeout parameter on the receiver can be used to map out
lost telegrams (either by external influence or collisions caused by a large number
of probes) and no error message appears. The value received last is retained over
2 to 20 transmission intervals and the alarm radio transmission timeout is only
then activated (display "----").