Content deleted Content added
Removed incomplete manufacturer ID table. Table contained only around 1/4 of all listed manufacturers and was over 20 years out of date. Removing the table encourages the user to look at the official HART manufacturer table (easily found with an internet search) and decreases both maintenance load on the editor and informality of the page. Additionally, the deleted table was presented in decimal, while HART IDs are typically presented in hexidecimal in industry. |
Tag: Reverted |
||
Line 16:
The protocol was developed by [[Rosemount Inc.]], built off the [[Bell 202 modem|Bell 202]] early communications standard in the mid-1980s as a proprietary digital communication protocol for their smart field instruments. Soon it evolved into HART and in 1986 it was made an [[open protocol]]. Since then, the capabilities of the protocol have been enhanced by successive revisions to the specification.
==Modes(unknown)==
[[File:Smart current loop positioner.png|thumb|Example of current loops used for sensing and control transmission. The HART protocol can be overlaid on the 4–20 mA loops.]]
There are two main operational modes of HART instruments: point-to-point (analog/digital) mode, and multi-drop mode.
| |||