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The relevant RSSI levels can be deduced from the output currents using the following graph:
The radio receiver has a sensitivity of about -10dB
V, and a good radio path should have a margin of at least 10dBµV
so the RSSI should ideally read at least 0dBµV, or 7.5mA, in each direction.
8.1.3 Radio Path Test Set (S2.6…S2.8 = 011)
This mode is identical to the Radio Commissioning mode described above, but the base-station
must
be fitted with an
Alphanumeric Display Module. The base-station is assumed to run from an internal battery, and to be used in
conjunction with a battery-powered
Nano_Link
outstation, making the test set portable.
The base-station is normally asleep, to conserve battery power. Every 10 seconds it interrogates the pushbuttons on the
display module. If any is pressed it wakes up and starts polling the outstation every 5 seconds. The display module can
be used to monitor the RSSI in both directions.
For added confidence, the base-station simulates activity on its digital inputs, which should be replicated at the
outstation. If the outstation’s digital outputs are fed back to its digital inputs, the activity should also be replicated on
the base-station digital outputs.
The system can be activated by pressing the ENABLE button on the display (or closing a switch connected in parallel
with it). The display remains active for 15 seconds after the switch is opened, following which the base-station goes to
sleep to conserve batteries.
-15
-10
-5
0
5
10
15
20
25
0.0
5.0
10.0
15.0
20.0
mA
RSSI (dBuV)
Содержание Nano Link IP67
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