HART handheld communicator issue

This post was last edited by liu530014416 on 2024-1-31 11:53. Everything is fine; if you disagree, give it a try. You gave me too many points; I’m going to upload a video. In the fifth case, by removing the resistor, the handheld device can still communicate.

This post was last edited by zhoudingshengs on 2024-1-31 at 11:49. For reference: 1. The term \"handheld operator\" does not specifically refer to the Emerson HART475; Emerson holds a high market share, and it is precisely because of the HART (Rosemount) protocol that it became successful. The renowned “*75” in the instrumentation world has essentially become a standard feature for every user, and various *75 models have come to symbolize hand-held controllers. In fact, there are many handheld controllers available on the market, such as those from Yokogawa, Honeywell, ABB, Fluke, Zhongkong, and Jingyi. 2. In addition to the HART communication protocol, the handheld controller supports other HART protocols as well: those invented by Emerson (Rosemount), which are currently the most widely used methods. Brain Brown Protocol: A type of Yokogawa monopoly; due to its high market share, this protocol has remained strong, and there is only one controller that supports it – the BT200. DE protocol: Honeywell transmitters using this protocol were available over a decade ago, but they gradually disappeared from the market. There are also FF, PA, Modbus, etc.

A has never been used…. Ours do not support this functionality; BC has been used, and some handwriting recognition devices do not require the use of resistors

It depends on whether the internal resistance of the power supply is sufficient; in your case, it’s clear that the internal resistance is not enough, so AD is the solution

I’m confused; as far as I remember, isn’t it sufficient to have enough resistance in the circuit? BCD should all work; A probably won’t. Is there a standard answer for this, or do anyone who has used it have anything to say?