IFM Electronic AS-Interface AC2520 Montageanleitung Seite 11

* periphery fault
A periphery fault is indicated if at least one of the signals AI1, AI2, AI3
or AI4 is outside the measuring range or if nothing is connected to at
least one analogue channel.
Measuring range of the Pt100 module
For the measuring ranges, the LED states and their meaning please see
the following table:
Range
-200 ... +850°C
< -219.4°C
-219.4°C ...
-200.1°C
-200°C ...
+850°C
+850.1°C ...
+883.6°C
> +883.6°C
Transmission time of the analogue values
The transmission time of the analogue values depends on the conver-
sion time of the analogue signals into digital signals in the AS-i mod-
ule and on the transmission time via the AS-Interface.
The conversion time for 4 Pt100 signals is 480ms.
The transmission time of the 4 16-bit values via the AS-Interface ideal-
ly is 7 AS-i cycles per value. For a cycle time of 5ms per AS-i cycle this
results in a transmission time of 4 x 7 x 5ms = 140ms via the AS-Inter-
face.
Thus the total transmission time for 4 temperature values ideally is
480ms (conversion time) + 140ms (transmission time) = 620ms.
Units
dec.
32767
-2194 ... -2001
-2000 ... 8500
8501 ... 8836
32767
Units
hex.
7FFF
F76E ... F82F
F830 ... 2134
2135 ... 2090
7FFF
LED AI1...AI4
analogue
flashes
on
on
on
off
Meaning
short circuit
below nominal
range
nominal range
above nominal
range
wire break
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