31.6.4 Restrictions - LT and EX Module
-
Power for the analog module should be separate
from the LT unit's power supply. When turning the LT unit ON, first
supply the module with power for 1 second or longer before you turn
ON the LT unit. After turning the power OFF, wait long enough
before powering on again to prevent malfunctions.
-
When using the analog module (set up with 4 to 20
mA), and signals are less than 4 mA or greater than 20 mA, an
abnormal data error message displays. In this scenario, inputs
retain their previous values before the error.
-
Internal communication between the LT unit and EX
module may experience a maximum delay of scan time + 20
milliseconds.
In addition, because the EX module (hardware) also has a delay, to
calculate the actual delay time for inputs and outputs, you need to
also add the EX module delay time.
-
The following analog modules do not detect analog
external power errors. For input modules, errors are detected as an
input data error.
-
EXM-AMI4LT
-
EXM-ARI8LT
-
EXM-AVO2HT
-
EXM-AMM6HT
-
When using inputs less than the Lower Limit for
the Input Range on the EXM-AMI4LT, an input range error is detected
unless the voltage setting is about -1 V and current setting is
about -4 mA. Using inputs less than the lower limit could influence
other CH, and lower their input values..
The number of Connectable EX modules
The number of EX modules that can be
connected differs depending on the display or EX module type used.
Please refer to the following table for details.
|
Series
|
Number of units
|
Connectable EX Modules
|
|
LT-3200 Series
|
1
|
All EX modules
|
|
2
|
EX module in group A, B and C, as below
|
|
LT-3300 Series
|
1
|
All EX modules
|
|
2
|
EX module in group A, B and C, as below
|
|
3
|
EX module in group A and B, as below
|
EX Modules in Each Group
|
Group
|
EX Module Name
|
|
A
|
EXM-DDO16UK
EXM-DDO16TK
|
|
B
|
EXM-DDI8DT
EXM-DDI16DT
EXM-DDO8UT
EXM-DDO8TT
EXM-DRA8RT
EXM-DRA16RT
EXM-DMM8DRT
EXM-AMI2HT
EXM-AMI4LT
EXM-AMO1HT
EXM-AVO2HT
EXM-AMM3HT
EXM-ALM3LT
EXM-AMM6HT
|
|
C
|
—
|
|
D
|
EXM-DMM24DRF
EXM-ARI8LT
|
Change from LT-3300 Series to LT-3200
Series
-
If an I/O is mapped to an I/O number (I12 to I15,
Q6 to Q15) that does not exist in the LT-3200 Series, the following
error message will appear.
-
If too many EX modules are connected, the
following error message will appear.
|
