GE VersaMax IC200PWR001 User Manual page 487

IC200ALG630
Analog Input, 16 Bit Thermocouple, 7 Channels
Cable Shield Connections
If possible, the cable should be grounded at the source device. If that is not
possible, the cable shield must be grounded at the source device. If that is not
possible, the cable shield must be grounded at the I/O module. This can be
done using an Auxiliary I/O Terminal (IC200TBM001, 002, or 005).
If the module is installed on a Terminal-style I/O Carrier (IC200CHS001, 002, or
005), shield connections can be made on an Auxiliary I/O Terminal that is
attached to the I/O carrier. If the module is installed on a Compact
Terminal-style I/O Carrier (IC200CHS022, 025), shield connections can be
made on an Auxiliary I/O Terminal that is mounted near the I/O carrier. Be sure
to ground the Auxiliary I/O Terminal Strip if you plan to use it for this purpose.
If the module is installed on a Connector-style I/O Carrier (IC200CHS003), the
cable shield can be connected directly to an Interposing Terminal
(IC200CHS011, 012, 015). Be sure to ground the Interposing Terminal. It is
recommended to use a shielded interposing cable as well between the
Interposing Terminal and the Connector Base. A custom shielded cable can be
made using the Connector kit (IC200ACC304). In addition, a custom shield
braid can be wrapped around standard Interposing Cables (IC200CBL105, 110,
120, 230). If this approach is used be sure to ground the braid.
Diagnostics
Alarm faults are reported if the processed value for a channel exceeds its
configured alarm limit. Over/Under range faults are reported if the millivolt value
for an input exceeds the limits of its span.
Open circuit is checked every time a thermocouple input is read (unless Open
TC checking is disabled). If the circuit is open, a fault is reported and the input
defaults to the configured channel default (this is 0 unless re-configured). If the
Thermocouple Type parameter has been configured as "none", open circuit
checking is not done. After an Open Circuit fault condition is corrected, the
module takes a few seconds to return to normal operation. During this time, the
module continues reporting the channel default input value. After the module
has recovered from the Open Circuit fault, it returns to normal inputs and
normal operation.
If there is a very large change in an input (for example, an input quickly goes
from 50mV to 400mV), the module may briefly report an Overrange fault on that
circuit even though the circuit is not actually over its configured upper limit. This
is temporary.
Thermistor Fault
A thermistor fault occurs if the calculated temperature value from the thermistor
is less than -10 °C or greater than +75 °C.
GFK-1504N Chapter 14 Temperature Sensing Modules
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