How to Improve Field Bus Wiring

Field bus systems are part of the modern automation backbone.

Field bus wiring is essential to modern automation networks. This wiring protocol is connected to human operators, Internet access gateways and the individual sensors and automation components that drive a facility. Often, the biggest block to field bus wiring is the lack of isolation between the individual legs of the network, leaving opportunity for improvement.

Things You'll Need

• Network cable grounding supplies
• Current limiter or surge protector

Instructions

1. Make sure each leg of the trunk line is isolated. This ensures any noise on the lines -- that would otherwise be detrimental to the circuits -- exists in a manner that naturally cancels one another.

2. Ensure all cable legs are galvanically isolated from one another. Each leg must communicate, but with the grounds at different potentials. Doing so ensures a surge affecting one leg does not affect the other. If this is not done, the current limiter -- or surge protection device -- may be rendered ineffective.

3. Use independent power conditioners for each leg of the field bus system. This offers a further layer of galvanic isolation from one leg to the next -- ensuring one leg remains isolated, in the event of catastrophic failure.

References

• Relcom: The Importance of Isolation for Foundation Fieldbus

Resources

• Fieldbus Foundation: Wiring Installation Guide