Wiring and connection issues for RS485 signals after passing through the safety barrier
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I’m a beginner with RS 485; I’ve been working on another 485 design recently. Since safety in the field is a requirement, six RS485 safety gates were added (1 for communication power supply and 5 for pure power supply). There are 6 RS485 sensors at the site. After installing the safety barrier, to facilitate wiring, one 2-core RS485 communication cable and one 12-core power cable were used – the power cable supplies power to the sensors, with the power coming from the safety barrier. The power cable is connected to the sensors via a distribution box, and the communication cable also passes through this distribution box. However, the actual internal wiring is as shown in the diagram below. I’m not sure if this way of wiring is correct; I would appreciate it if experts could give me some advice. Thank you!
The wiring is incorrect. . . One communication safety barrier and six power supply safety barriers should be used. However, intrinsically safe instruments with RS485 outputs are generally powered by intrinsically safe voltage regulators, without the need for safety barriers. It is said that when using safety barriers for power supply, communication issues can lead to instability in the measured values, resulting in accuracy errors, especially when the measured values are small. Which brand of intrinsically safe gauge are you using, and what parameters is it measuring? .
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Only a intrinsically safe sensor + intrinsically safe cable + safety barrier can constitute an intrinsically safe system; having a safety barrier alone does not make something intrinsically safe.
The wiring is incorrect. . . One communication safety barrier and six power supply safety barriers should be used. However, intrinsically safe instruments with RS485 outputs are generally powered by intrinsically safe voltage regulators, without the need for safety barriers. It is said that when using safety barriers for power supply, communication issues can lead to instability in the measured values, resulting in accuracy errors, especially when the measured values are small. Which brand of intrinsically safe gauge are you using, and what parameters is it measuring? .