Board-to-Board Bus Daisy Chain - Ground Loop?

[digi001]

Question For a Board-to-Board Bus structure like CAN :

---Say 4 PCBs hooked up from 1 PSU
---All PCBs Daisy Chained with CAN Bus
---Very Noisy Industrial Environment

Does it make sense to possibly isolate each CAN bus for improved noise issues and eliminate any possible ground loops?

 

[ckshivaram]

BACK to basics... CAN was never designed for a common ground system as it is a distributed system with different grounds... any number of nodes there will be no common ground..

It uses differential bus technique for minimising the noise in a signal...Reducing industrial noise is left to user to do externally

 

[digi001]

Ok, Yes so CAN is differential and uses a Transceiver.

And say 3 PCBs are powered by 400V-DCtoDC-24V-DCtoDC-5V then 5 other PCBs powered (same)400V-DCtoDC-(same)24V-DCtoDC-12V then individual PCB Linear Regs to 5V.

All CANs are connected. Is grounding loops even an issue here?

 

[ckshivaram]

grounding is never an issue in CAN BUS communication. . Is your source 400V DC... each board will have a regulator of its own and does not need common ground.

sensors can be placed anywhere in the system and have transceivers o each board that in turn are connected through CAN bus to each other... we cant expect all sensors to have a common ground...

Hope you get my point...

 

[digi001]

Ok yes I understand....Thanks!