Honeywell recently obsoleted the STT350 series. There are other STT series that Honeywell had previously obsoleted. If you get a call for one of these series, you will need to cross that series over to the STT750 or STT850 series. A major difference between these two temperature transmitters is that the STT750 uses HART communication. The STT850 offers both DE and HART. HART is the most common form of communication in transmitters today. DE is Honeywell’s original form of communication. If you are replacing an older Honeywell transmitter, you will need to sell the STT850 because that older transmitter is going to be DE. We are going to be stock both the STT750 and the STT850.
You may ask why stock both? Why not just stock the STT850 since it covers both types of communication. The simple answer is price. The STT750 is a less expensive option as opposed to the STT850.
For more information please contact your local George T. Hall Company Representative.