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The calibration means that a reading of 4000 corresponds to full scale. A reading between 4001 and 4095 indicates that
the input is over-range.
If SENSE is midway between 0V and 12V,
Nano_Link
assumes the transducer to be a strain gauge pressure sensor.
These give an output voltage that is proportional to the supply voltage and to the pressure, and are normally calibrated
to give 100mV FSD when powered from 12VDC.
Nano_Link
accommodates this by changing the reference to 1.00%
of 12V. It thus self-adjusts for tolerances on 12V:
Note that the 12V supply from
Nano_Link
is only present when the station is awake. A base-station is
constantly awake, as is an outstation in Constant Power Mode. However, a battery-powered outstation
conserves power by only energising the transducers when needed. It will thus activate the 12V supply only when
it receives a command requesting an analogue reading. The supply is then raised for a short period before
sampling the analogue, to give the transducer time to stabilise. Power is switched off immediately after the
response has been sent to the base-station.
If the user wishes to test transducers at a battery-powered site, he should set the station to constant power mode for the
duration of the tests, remembering to return it to normal afterwards to conserve the battery.
For more information on operating modes refer to Chapters 7 and 8.
A N A L O G U E S
O / P
I N P U T S
1 -
2 -
+
1 -
1 I
1 +
2 -
2 I
2 +
-
3-wire current transducer with common 0V,
powered by
Nano_Link
+ -
O/P
+ -
O/P
A N A L O G U E S
O / P
I N P U T S
1 -
2 -
+
1 -
1 I
1 +
2 -
2 I
2 +
-
3-wire current transducer with common 0V,
externally powered
+ -
O/P
+ -
O/P
0V
External supply
+10…24V
A N A L O G U E S
O / P
I N P U T S
1 -
2 -
+
1 -
1 I
1 +
2 -
2 I
2 +
-
4-wire strain gauge transducer,
powered by
Nano_Link
+ -
A
B
+ -
A
B
Содержание Nano Link IP67
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