Connection between the proximity switch and DCS
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What additional cards are needed for connecting the proximity switch to the Zhejiang University ZHKD DCS system, and what is the wiring method? Automatic control instruments
Use a frequency card to measure the switching frequency of the proximity switch
What is this proximity switch used for? Isn’t it just a DI? Is it to measure the rotation speed?
If the proximity switch is a simple switch, it represents a digital signal: DI on the input card and DO on the output card
Specifically, check the wiring method of the DI card.
What is this proximity switch for? If it’s in that position, it’s just a regular DI
If it is an approach switch signal for the Namur signal, safety gate manufacturers generally provide corresponding cards to convert it into a dry contact signal before feeding it into the DCS； In the case of continuous quantity measurement (some call it encoders), it is actually a frequency signal; by connecting a frequency conversion (isolation) circuit, this signal can be converted into a standard 4–20 mA signal for transmission to the DCS. It can also be fed directly into the DCS’s frequency card, depending on whether explosion protection or isolation is required.
DI is used for position measurement, while PI is used for speed measurement