DRAFT - 11 December 2014
DRAFT - 11 December 2014
2
DRAFT - 11 December 2014
INM MTL4850_54 Rev4
The multiplexer module, MTL4850 or MTL4854, uses a plug-in style with fixing screws to
provide a simple and secure installation method onto the backplane.
Up to 32 field devices can be accommodated by each HART multiplexer module, which is
then connected via an RS485 to USB (or Ethernet) converter, to the PC running the HART
maintenance software. Depending upon the management software, up to 63 of the multiplexer
modules can be connected to it, making a potential count of 2016 smart field devices on one
serial link. See Figure 2.1 for a diagrammatic impression of this structure.
For intrinsically safe applications, consideration must be given to the safety parameters for
each field loop. For further information, please refer to MTL or your local representative.
The MTL4850 has a single HART modem to service the channels connected to the module
whilst the MTL4854 has four HART modems. The latter enables simultaneous communication
with multiple field devices through a single multiplexer, providing obvious benefits for
applications where speed of data access is important.
NOTE
For any application of the multiplexers where connection is made to signals which are part
of a safety instrumented system then the MTL4850 must be used. Refer also to the safety
manual for the MTL4850 available from the MTL website.
HART
®
is a registered trademark of the HART Communication
Foundation
Safe area
Hazardous area
Figure 2.1
- System Overview (typical installation)
Up to 63 MTL4850/54 modules
