Removable PCB terminal block cold junction compensation

A method of implementing cold junction compensation on an input module including a terminal block and a printed circuit board, the terminal block being configured to receive at least one pair of first and second electrical wires of an external thermocouple, the terminal block including first and second connector assemblies for electrically coupling the first and second electrical wires of the external thermocouple to the printed circuit board, the method comprising:

• measuring a temperature using a sensor on the printed circuit board;
• measuring a temperature or voltage using a first internal thermocouple of the first connector assembly of the terminal block, the first internal thermocouple having two first conductive legs which are formed of different materials and are separated at an end to form a first jaw connector for physically and electrically connecting or disconnecting an edge of the printed circuit board to or from the terminal block;
• determining a cold junction temperature for the external thermocouple based on the temperature measurement from the sensor and the temperature or voltage measurement from the first internal thermocouple;
• and
• performing the cold junction compensation for a measurement of a hot junction temperature of the external thermocouple using the determined cold junction temperature,
• wherein the second connector assembly includes a second internal thermocouple having two second conductive legs which are formed of different materials and are separated at an end to form a second jaw connector for physically and electrically connecting or disconnecting an edge of the printed circuit board to or from the terminal block,
• wherein a temperature differential between the terminal block and the printed circuit board is determined based on a voltage difference between the two legs for each of the internal thermocouples, and the cold junction temperature is calculated based on the temperature measured by the sensor and the determined temperature differentials for each of the internal thermocouples, and
• wherein the cold junction temperature is calculated based on an average of the temperature differentials for each of the internal thermocouples of the first and second connector assemblies.

A non-tangible computer readable medium storing computer code, which when executed by a processing circuit, performs a method of implementing cold junction compensation on an input module including a terminal block and a printed circuit board, the terminal block being configured to receive at least one pair of first and second electrical wires of an external thermocouple, the terminal block including first and second connector assemblies for electrically coupling the first and second electrical wires of the external thermocouple to the printed circuit board, the method comprising:

• measuring a temperature using a sensor on the printed circuit board;
• measuring a temperature or voltage using a first internal thermocouple of the first connector assembly of the terminal block, the first internal thermocouple having two first conductive legs which are formed of different materials and are separated at an end to form a first jaw connector for physically and electrically connecting or disconnecting an edge of the printed circuit board to or from the terminal block;
• determining a cold junction temperature for the external thermocouple based on the temperature measurement from the sensor and the temperature or voltage measurement from the internal thermocouple;
• and
• performing the cold junction compensation for a measurement of a hot junction temperature of the external thermocouple using the determined cold junction temperature,
• wherein the second connector assembly includes a second internal thermocouple having two second conductive legs which are formed of different materials and are separated at an end to form a second jaw connector for physically and electrically connecting or disconnecting an edge of the printed circuit board to or from the terminal block,
• wherein a temperature differential between the terminal block and the printed circuit board is determined based on a voltage difference between the two legs for each of the internal thermocouples, and the cold junction temperature is calculated based on the temperature measured by the sensor and the determined temperature differentials for each of the internal thermocouples, and
• wherein the cold junction temperature is calculated based on an average of the temperature differentials for each of the internal thermocouples of the first and second connector assemblies.