Rockwell Automation Publication 1715-UM001J-EN-P - December 2020
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Chapter 2 Installation Instructions
Figure 50 - 1715-TASIF16 and 1715-TADIF16 Analog Input Termination Assemblies
Analog Input Slew Tolerance
It is possible during sustained periods of abnormal input current slewing that
channels can be declared faulted as a consequence of diagnostics that are
otherwise designed to verify the channels are operating within their designed
safety accuracy.
To avoid spurious declaration of channel faults, it is necessary to ensure that
the input signal condition satisfies the maximum slew rate criteria that are
defined in the 1715 Redundant I/O System Specifications Technical Data,
publication
. So it can be necessary to condition the input signal
with low-pass filtering or sensor slew rate configuration.
Analog Input Module Field Devices
If there are two field devices, you normally connect them to two channels of a
fault tolerant pair of modules, for example to channel 0 and to channel 1.
The two input values (0 and 1) then must be voted by using logic or a function
block in the application program. This is accomplished by taking either the
lowest or highest value, depending on the application. The other option is to
use the two values in two simplex input modules, for example, both using
channel 0. In this case, the values must still be voted in the application
program in the same way as previously stated, but the system has less fault
tolerance, as the loss of one module removes one of the inputs.
32120 M
Fuse
Fuse
Holder
Channel -
C
TB1
TB2
CH0 CH1 CH2 CH3 CH4CH5 CH6 CH7 CH8CH9 CH10CH11CH12CH13CH14CH15
FS1
FS3
FS5
FS7
FS2
J1
16
c
c
c
c
1
1
1
1
16
16
16
J2
J4
J3
FS4
FS6
FS8
FS9
FS11
FS13
FS15
FS10
FS12
FS14
FS16
FH1
FH2
FH7
FH6
FH5
FH4
FH3
FH9
FH8
FH10
FH16
FH15
FH14
FH13
FH12
FH11
FH1
F1
OV OV CH0 CH1 CH2 CH3
CH4 CH5 CH6 CH7 CH8 CH9
CH10 CH11 CH12 CH13 CH14 CH15
TB1
TB2
J1
J2
16
16
1
1
1715-TADIF16
Analog Input Duplex
Termination Assembly
1715-TASIF16
Analog Input Simplex
Termination Assembly
45238
32120 M
Terminal Block Cable This Side
Field Connections This Side
Fuse Cover
Fuse Covers
Coding Pegs
Coding
Pegs