IMC CANSAS - Reset-Plug; CAN Data Transfer Rate

40 Startup
imc CANSAS Users Manual - Doc. Version 1.9 - 05.12.2014© 2014 imc Meßsysteme GmbH
2.6.5 Reset-plug
To set a CAN module to its shipping condition you need a reset plug. That 9-pin standard DSUB plug must
be jumpered between Pins 3 and 4.
2.6.6 CAN data transfer rate
As signal lead lines become longer,
the maximum reliable data transfer
rate decreases. Furthermore, the
possible data rate depends on the
bus timing, which in turn is
determined by the hardware
configuration and software version.
Data rate over line length for CANSAS-modulse or imc-USB Interface
The diagram shows the transfer rate for present-day imc CANSAS- modules and the imc USB Interface
Line length [m]
Data rate [kBit/s]
Note
Devices from imc are built with electrical
isolation from the bus. Devices without
electrical isolation achieve somewhat higher
values for the maximum line length: 40m at
1000kBit/s or 100m at 500kBit/s.
25
1000
85
500
200
250
500
50
1000
20
Net data rate
Conversely, the net data rate depends on the package size and on whether the Standard Frame or the
Extended Frame is used. For instance, if each imc CANSAS message has been optimally packed in 8byte
chunks, the Standard Frame is used and there are no further subscribers connected to the node, the rate
reaches 576,6 kBit/s, amounting to 36kSamples/s. The table shows the net data rates for 1 MBit/s.
Data length
Net data rate with
Data length
Net data rate with
Standard Frame
Extended Frame
Standard Frame
Extended Frame
0
-
-
5
360,4 kBit/s
305,3 kBit/s
1
72,1 kBit/s
61,1 kBit/s
6
432,4 kBit/s
366,4 kBit/s
2
144,1 kBit/s
122,1 kBit/s
7
504,5 kBit/s
427,5 kBit/s
3
216,2 kBit/s
183,2 kBit/s
8
576,6 kBit/s
488,5 kBit/s
4
288,3 kBit/s
244,3 kBit/s