SERIAL COMMUNICATIONS EXAMPLE
-34-
PROCESS CONTROLLING SYSTEM
Six Model IMS units with Serial Communication Option
are used to monitor and control water tank levels at a
chemical manufacturing plant. The tanks are at different
areas of the factory and one IMS is located at each of the
tanks. The communications lines are run to an industrial
computer located in the production offices.
The drawing below shows the Current Loop set-up. Each
IMS is given an address and programmed accordingly
(Program Module #7). A baud rate of 1200 is selected.
An application program is written, which sends and
retrieves data from the IMS units.
Note: On all IM indicators, the SO+ and the +20 mA SRC
are connected internally. Therefore it is not necessary to
have this terminal tied to any other terminal on the unit if
that unit is serving as the loop supply source.