Honeywell MCT404, Руководство пользователя

Страница: 22 / 166

2. Before you begin
2.2. Transmitter/Communication characteristics
10 MC Toolkit (MCT404) User Manual Revision 3
methods. In this case, the same FSK modulation method is used for conveying levels of PV (and other
variables) and also for communications.
CAUTION:
Before connecting to a HART transmitter, ensure that the MC Toolkit is not set up for DE
communications, whose current amplitude can "bump" process variables in either point-to-
point mode or in multi-drop mode.
Non-Honeywell HART Transmitters and Devices
HART-capable transmitters from any manufacturer and for any specific purpose are designed to
common-agreement standards that provide for inter-operability.
Guidelines published by the HART Communication Foundation enables manufacturers to design devices
that communicate via a set of standard commands and responses.
The FDC application software supports the HART Revision 5.0, 6.0 and 7.0 commands that are exposed
through the HART Communication Foundation Device Description files. For more information, refer to
tables in the Reference Data section 5.8.
The FDC uses Device Descriptions stored in the Pocket PC to communicate to all universal, common
and device specific commands. MC Toolkit will come with all HART Registered (updated once per
quarter) Device Descriptions pre-loaded.
URV URV
Figure 2-3 Honeywell DE Mode Value Scaling