Micromod MOD: Modcell 2050R Users Guide - Manual (Page 152)

IB-23C650
BASIC OPERATION
A transition in the state of either digital input (opened to closed, or closed to
opened) will now cause a set-point transfer. For example, if the digital inputs
are set up for set-point selection between LOC, LO3, LO4, and REM (using
DIRECT action, with Input 2 enabled and local/remote transfer allowed), a state
change of the digital inputs to DI-1 closed and DI-2 opened will cause a
transfer to LO4. The following table shows the results of digital input state
transitions of two digital inputs used for set-point transfer between LOC, LO2,
LO3, and LO4 and for transfers between LOC, LO3, LO4, and REM using
DIRECT and REVERSE action.
Example of Digital Input Action vs Set-point Source for Two Digital Inputs
Digital Input Action*
DI-2
DIR REV
DI-1
DIR REV
Set-Point Source
(L1,L2,L3,L4)
selected
SPT Source
(L1,3,4,R)
selected
SPT Source
closed open closed open LOC LOC
closed open open closed LO2 LO3
open closed closed open LO3 LO4
open closed open closed LO4 REM
Output Tracking using Digital Input
When output tracking is enabled as a digital input function and the assigned
digital input goes ON, then the controller goes to manual and the current
proportioning output tracks input 2 (an electrical not temperature input). Auto
and Manual keys are ignored, front panel adjustment is not allowed, autotune
is not allowed and, if the computer activity timer is not in use, the mode
annunciator (upper 3 character display) will indicate TRK. When the digital
input goes OFF, the controller transfers bumplessly back to its original mode.
CONTROL OUTPUT LIMITING
High and low output limits are entered in MA. OUTP MENU. The output
limiting function applies when the controller is operating in automatic, and also
in manual if manual limiting is selected. If manual limiting is not selected, the
manual output can be adjusted to its maximum or minimum value regardless
of the limit settings.
ALARMS
Four display alarms and up to three alarm relays may be configured to
respond to alarm conditions. The trip action on the relays may include any
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