MoTeC C185 - Manual (Page 71)

66 Appendices MoTeC
CAN Bus Bandwidth Limit
The total available CAN bandwidth available on a single CAN bus is
1 Mbit/sec.
The bandwidth used by the total of all devices on a particular CAN bus must
not exceed approximately 90% of this value (900000 bits/second)
If the total bandwidth required exceeds this specification then some devices
should be connected to the second CAN bus.
Note: C185 Dash Manager will warn if the bandwidth is likely to be exceeded.
VIM
Approximate Bandwidth = Total Measurement Rate (samples/sec) x 30 (bits
per sample)
Note: The Measurement Rate for each input is equal to the logging rate for
that input or 50 Hz, whichever is higher.
Example Calculation
4 channels at 2000 Hz
20 channels at 500 Hz
40 channels at 20 Hz (Occupies 50 Hz)
Calculation:
Total Measurement Rate = 4 x 2000 + 20 x 500 + 40 x 50 =
20000 (samples/sec)
Approximate Bandwidth = 20000 x 30 = 600000 (bits/sec)
E888/E816
Device on first CAN Address
Bandwidth = 145000 (bits/sec)
Device on second CAN Address
Bandwidth = 55000 (bits/sec)
Other Devices
BR2, SLM , PLM Negligible
SDL, ADL2, MDD, M800 ECU TBD