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D1300M Modbus Modules with Thermocouple Input


The D1300M modules measure thermocouple temperature sensors. Thermocouples consist of two wires made from dissimilar metals. The wires normally are joined or bonded together at one end to create a junction. This junction of different metals generates a predictable voltage output with changes in temperature.

The D1300M thermocouple input modules use an isolated 15-bit analog to digital converter to measure the thermocouple output voltage, performs cold-junction compensation and linearizes the digital data. The digital data values are scaled into 16-bit unsigned integer data format that represent a percentage of the full-scale input range. The data values are transmitted to a host computer using the Modbus RTU serial protocol via an RS-232 or RS-485 serial port.

The D1300M thermocouple input modules contain two discrete digital input and three open-collector digital outputs. The digital outputs can be used to control solid-state relays and annunciators.  They can be pulled up to +30Vdc and sink up to 30mA without damage.  The discrete digital inputs can accept +/-30Vdc signals without damage.  The discrete switching levels are <+1Vdc = logic “0”, >+3.5Vdc equals a Logic “1”.

Because the Modbus protocol does not support Echoing the RS-232 versions of D1000M series are limited to one module per serial port. Applications requiring more than one module should use RS-485.

Use the links below to download a Datasheet, User’s Manual or view the Modbus Scaling Example.

Download Datasheet

Download Manual

Modbus Scaling Overview

The D1300M series modules can also be mounted on a DIN-Rail using the MK-1 mounting kit.

Thermocouple Measurement Ranges:
[one_half]J= -200 to +760 C
K= -150 to +1250 C
T= -200 to +400 C
E= -100 to +1000 C [/one_half][one_half_last]B= 0 to +1820 C
S= 0 to +1750 C
R= 0 to +1750 C
C= 0 to +2315 C[/one_half_last]


Additional information

Dimensions 3.6 × 2.45 × 1.1 in

• Types: J, K, T, E, R, S, B, C
• Accuracy (errors from all sources) from 0 to +40C ambient: +/-1deg C max (J,K,T,E types). +/-2.5 deg C max for (R,S,B,C types).
• Resolution: 1 degree (C or F).
• Common mode rejection: 100db at 50/60 Hz.
• Lead resistance effect: <20uV per 350 ohms.
• Input burnout protection to 250 VAC.
• Input impedance: 100 megohm min.
• Three open-collector digital outputs.
• Two digital inputs.
• Open thermocouple indication.
• Automatic Cold-junction Compensation