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3.4.3 Analogue Inputs
Nano_Link
has two real inputs and two pseudo inputs (which read the battery voltage and the radio received signal
strength):
3.4.3.1 Real Inputs:
The two real inputs are very similar, and are read to a resolution of 12-bits (i.e. 0…4095). The equivalent circuit of
input 1 is as follows:
Analogue input 2 is identical, but omits the SENSE detector.
Nano_Link
generates an internal 12V supply, which is present all the time if the unit is configured for mains power,
but switched off in battery-powered units when not needed, to conserve power. It is used to power the analogue input
and output circuits, and the radio transmitter. It is also available for powering transducers if required.
If SENSE is within 1V of either 0V or 12V the input sensitivity is set to 0...100.0mV. Linking 1I to 1+ converts this to
a current input of 0...20.00mA. This is compatible with both 0…10mA and 4…20mA transducers, and can detect both
over-range and under-range errors. The means of connecting current transducers is thus:
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 +
-
2-wire current transducer input,
powered by
Nano_Link
+ -
+ -
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 +
-
2-wire current transducer input,
externally powered
+ -
+ -
0V
External supply
+10…24V
0V
10Vsw
+
-
SENSE
Vout
1M
1M
1-
1I
-
+
1+
1M
27K
47
H
47
H
5
27K
Содержание Nano Link IP67
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