IFM Electronic AC2521 Montageanleitung Seite 11

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 2 analogue input signals into digital signals is
< 1ms. The transmission time of the 2 16-bit values via the AS-inter-
face ideally is 7 AS-i cycles per value. For a cycle time of 5ms per AS-i
cycle this results in a transmission time of 2 x 7 x 5 ms = 70 ms via the
AS-Interface.
Thus the total transmission time for 2 analogue values ideally is 1 ms
(conversion time) + 70ms (transmission time) = 71 ms.
Example: Transmission time of 4 analogue channels
The conversion time for 4 analogue input signals into digital signals is
< 1ms. The transmission time of the 4 16-bit values via the AS-inter-
face ideally is 7 AS-i cycles per value. For a cycle time of 5 ms per AS-i
cycle this results in a transmission time of 4 x 7 x 5 ms = 140 ms via the
AS-Interface.
Thus the total transmission time for 4 analogue values ideally is 1 ms
(conversion time) + 140 ms (transmission time) = 141 ms.
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