PRO-TC-MAN-17V01 (0802)
Copyright © 2017 Define Instruments
12
C Multiplexing
The Multiplex (
MPX
) feature was designed for PLC interface, and allows the
PLC to determine, via the controller's 'Pk/Val' and 'Hold' function pins (see 3.6),
which temperature channel will be used as a data source for the analog output.
To activate this feature, your analog output data source must be set to
MPX
(see 6.6B). When you activate
MPX
, the default functions of the 'Pk/Val' and
'Hold' pins will be deactivated, and the pins will be used to determine which
temperature channel is used for the analog output, as shown in the table below.
Channel
Pk/Val
Hold
TEMP 1
OFF
OFF
TEMP 2
ON
OFF
TEMP 3
OFF
ON
TEMP 4
ON
ON
Note that when changing the 'Pk/Val' or 'Hold' pins in
MPX
mode, you need to
allow a settling time of at least 0.5 seconds before reading the analog output
current.
5.5 - Peak & Valley
Peak and Valley are the maximum and minimum values measured since the instru-
ment was turned on or reset. (These values differ from
MAXTMP
and
MINTMP
, in
that they will hold the maximum and minimum values until they are reset.)
The Peak and Valley data source can be set (in 6.3F), to a range of options as shown
in table 5.1.
Peak and Valley can be viewed from the front panel using shortcut keys (see 2.3),
or appear continually on the main display (if you set one of these variables as your
display data source). They can also be reset via the front panel (2.3), the rear pins
(3.6), or by restarting the controller.
While 'Peak' and 'Valley' have their own data source, they can also be
used as data
sources
- for the display, analog output, serial output, or setpoint control.
