Rules for Honeywell's SCT Smart Configuration Toolbox which talks Honeywell's DE protocol (a binary oscillating square wave 4ma/20mA that is frequently referred to as the Honeywell bump) to Honeywell's field instruments like ST3000 pressure transmitters and the SMV multivariable.

The original, first generation SCT kit has metal clad PCMCIA card which connects to an external modem.   The PCMCIA card and modem are the same hardware since introduction, the software has gone through multiple updates (from floppy to CD, too).  

The 2nd generation SCT was announced in May or June 2008, supposedly USB compatible.  Comments below concern only 1st generation SCT.

1)  Transmitter must be powered

2)  Loop must have a minimum of 250 ohms of resistance.

3)  The SCT field leads MUST be connected across the transmitter's + and (-) terminals (not the test terminals, or the meter terminals).  

IMPORTANT: neither SCT nor the SFC (handheld communicator) will talk if the leads are connected across the loop's load resistor.  The load resistor is functionally equivalent to the analog input of the DCS/PLC/controller/recorder/indicator, which will not work for DE communications.  

The transmitter + & (-) terminals are functionally equivalent to I/S barrier points, or equivalent points in loop junction boxes.

It doesn't matter how a HART communciator connects in a loop, SCT/SFC/DE is not HART.

4)  If you've just installed the SCT software on the PC, you MUST restart Windows.

5)  If you launch SCT and SCT does not see' the PCMCIA card, close SCT and re-launch.

6)   If you upload from the SMV multivariable, the upload take 4 minutes, 50 seconds.   Grass grows faster. 

7)  Not all Honeywell temperature transmitters talk DE.  Honeywell pressure transmitters with a blue painted end cap are HART transmitters, not DE transmitters.

Budd