Eurotherm Carbon Probe AP1 In-Situ


SKU: Carbon Probe


Cable Assemblies

Miscellaneous and Accessories


Eurotherm Carbon Probe AP1 In-Situ

Eurotherm Carbon Probe Spec Sheet (PDF)

The AP1 is a consumable item, like a thermocouple, which is mounted with its tip in contact with the furnace atmosphere, ideally close to the working zone. The probe produces an output voltage which, in conjunction with the process temperature and atmosphere, can be interpreted in terms of the atmosphere carbon potential of the furnace. The probe is designed to be used with controllers with a high impedance input. The Eurotherm AirRef enclosure provides a continuous reference air supply to support the standard operation of the probe.


Accuracy +/- 0.05 weight % carbon in normal operating range
Power Supply No
Mounting No
Options None
Isolation No
Ports No
Port Parameters No
Readout % carbon probe into 8MOhms
Output 1.00-2.00V dc
Power Consumption No
Response Time Less than 1.0 second
Thermocouple Type K, Type N, Type R, Type S


In-situ atmosphere measurement
Repeatable product quality
Energy cost savings
Improved Overall Equipment Effectiveness (OEE )


Key Features:
The AP1 In-Situ probe offers:
High repeatability
A burn-off port as standard
Rapid response
Measurement with Thermocouple Types K, R, S, N, or without a thermocouple
Compatibility with a wide range of process controllers


Eurotherm Carbon Probe AP1

The AP1 In-Situ Carbon probe is a direct and continuous carbon potential probe. It uses a patented design which features a cylinder of special zirconium oxide formulation, welded into the end of an alumina tube by means of a eutectic welding process – the resultant homogenous structure provides a very robust design. The probe sheath is a high temperature special alloy with a flow-through tip design to minimize soot collection and maximize sensor response. External signal and thermocouple connections are made via a quick disconnect plug, this enables a quick and reliable installation.

The probe can measure very low oxygen partial pressures with extreme accuracy and repeatability. It can be used to control furnace atmospheres and gas generators over a full range of carburising and hardening applications.


Works in all common reducing atmospheres:

Nitrogen/natural gas


The AP1 probe is suitable for high temperature carburizing heat treating, carbonitriding and endothermic gas generators. It should not be used for nitriding applications.

An inlet port for the supply of reference air to the inner electrode is in the head of the probe, along with the electrical connections to the inner and outer electrodes. The probe is generally fitted with a thermocouple to give the process temperature within the probe tip region and is also fitted with a “burn-off” port to allow the burn-off of carbon/soot deposits on the sensor tip, as requried.

Additional information

Weight 10 lbs
Dimensions 36 × 5 × 5 in

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