Ask Control Engineering
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Which version of HART?
October 18, 2011
Dear Control Engineering: Given that HART has gone through multiple revisions, if I look at an individual device, how do I tell which generation it is?
It’s true that HART has been updated over its history, but it has retained a high degree of backward compatibility. Still, there are situations where identifying which revision applies to a given piece of hardware could be useful. One sure thing is that a WirelessHART device uses HART 7, but wired devices aren’t so easy. Here’s some advice from Ron Helson, executive director of the HART Communication Foundation:
"If you need to know the revision level of a HART-enabled device, here are a few things to consider. HART 5 represents the vast majority of installed devices – going back to units from 1993 and representing more than 95% of all HART devices. HART 6 and HART 7 devices are relatively new so they make up the balance of the devices. If you device is more than 5 or 6 years old, it is probably a HART 5 device. Likewise, if your device is a WirelessHART device, it must be a HART 7 device which is the latest revision of the HART Specification.
"There are several ways to determine the revision level of a device but here are two of the easiest methods. The best way is to ask the supplier who can confirm the revision level using the device model and serial number. Or, you can visit www.hartcomm.org and check the Product Catalog. Simply use the search tool to find the device and the supplier, click on the device model number and the HART revision level is listed in the product profile."