Help needed - What protections does my circuits need?

Hello,

I have been developing a remote data acquisition system composed by one data acquisition and operation circuit which reads values from 4-20mA sensors and sensors with digital pulse outputs, one circuit to received solar energy and recharges a 12 V battery, and a circuit to do the 12v -> 24 v conversion (to supply the 4-20 mA sensors). A battery supplies the power to all the circuits and sensors.

Besides the EMC protection, what others kinds of protection should I implement in each circuit I have?
- ESD?
- Power input protection for overvoltages ? Using TVS?
- Power input protection for reverse polarity ? Using diodes in parallel ?
- Current-limiting circuit for each 4-20mA sensor present?
- What about an earth connection? Should I connect it to the battery GND?

Is there any book that treat these issues above?

Thank you,
rprodrigues

You should consider using isolation transmitters. They will free you from lots of troubles in potential.

1. protect your DAQ from dangerous voltage.
2. isolate the gound from the sensor and DAQ, and get clean datas.

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