QUESTION:  
How can I protect the current inputs of a C7-633P?

ANSWER:  
A suppressor circuit is sensible in the following cases, among others:

• Wrong wiring of the input during the commissioning (e.g. 24 V are applied accidentally)
• A fault of the sensor may cause e. g. a short circuit. Due to the damaged shunt resistor on the C7, the device would have to be sent in for repair.

Subsequent image shows a wiring diagramm, with which you can protect current inputs of a C7-633P.

Fig.1: Suppressor Circuit Analog Input ( 14 KB )  

Used Devices:
PTC: Company EPCOS, Order number B59980-C80-A70
Zenerdiode: Company Motorola, Order number 1N5339 (5,6V; 5W)