Allen-Bradley 2080-DNET20, Руководство пользователя

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12 Rockwell Automation Publication 2080-UM004C-EN-E - March 2015
Chapter 2 Install and Wire Your Module
Wiring Considerations and
Applications for 2080-TC2 Type of CJC Sensor
The CJC sensor is a non-polarized, passive negative temperature co-efficient
thermistor (EPCOS B57869S0502F140). It is readily available in the market
with most third party suppliers/vendors.
Wire the CJC Thermistor on the 2080-TC2 Module
The position for the thermistor, as illustrated, helps to compensate for
thermoelectric voltages developed at screw junction equally for thermocouples
connected to channels 0 and 1. If the bead is not in proper contact with the screw,
there will be deviation in readings due to inadequate isothermal compensation.
Wire the Thermocouple Module and Thermocouple Sensor
in the Field
Connect the thermocouple sensors directly to the module terminals.
IMPORTANT
CJC Channel Error
The CJC channel on 2080-TC2 has a worst-case error of ±1.2 °C @ 25 °C.
This error does not include the manufacturer-specified sensor error
±0.2 °C @ 25 °C.
6.5 max
50 ± 2
0.25
2.41 max
5m
5m
B3
A3
1. Connect the thermocouples to
channel 0 and 1, respectively.
Then, connect and screw the
thermistor to terminals A3 and B3.
2. Once fitted, bend the black bead
of the thermistor such that it
makes contact with the A2 screw
securely.
A1 A2 A3 A4 A5 A6
B1 B2 B3 B4 B5 B6