Digital Immersion Probe Precisely Measures Moisture in Oil

E+E Elektronik's rugged stainless steel MOP301 probe can be used in oils up to 120 °C (248 °F) and 20 bar pressure. By DA Editor / 11 Apr 2022

E+E Elektronik’s new MOP301 immersion probe precisely measures the moisture in transformer, lubrication or hydraulic oils as well as diesel fuel, with its main application being preventive maintenance of equipment and machinery. The stainless steel probe can be used in oils up to 120 °C (248 °F) and 20 bar pressure, with measured data for water activity, temperature and absolute water content available via the RS485 interface with Modbus RTU protocol.

Excellent measuring performance, rugged design

The E+E humidity sensing elements used in the MOP301 are characterized by their long-term stability and resistance to contamination, forming the basis for high-precision and reliable humidity and temperature measurement. 

The immersion probe is housed in a rugged, stainless steel enclosure, with protection class IP66, an oil-resistant cable and a moulded M12 connector. It can be used in a temperature range of -40 to 120 °C (-40…248 °F) and at up to 20 bar pressure. 

Various probe and cable lengths and the lean design enable particularly flexible installation of the MOP301, and thanks to the practical slide fitting, the immersion depth can be precisely set and changed if needed. In addition to this, an optional ball valve means that the probe can be installed and removed without interrupting the process and under pressure. 

Measured values and interfaces 

The MOP301 delivers oil moisture content as an absolute or relative value. The water activity (aw) states the relative moisture content of an oil and describes the relationship between the actual and maximum possible amount of dissolved water. The aw value reveals how close the oil is to the saturation point at a specific temperature. 

The MOP301 calculates the water content based on the measured water activity and temperature, with moisture content expressed in absolute figures (ppm or mg water / kg oil). The oil-specific parameters required for calculation can be factory pre-configured, written via Modbus RTU, or set retroactively with the aid of the PCS10 Product Configuration Software.

Extensible to a sensor unit

The MOP301 is also compatible with the Sigma 05 sensor hub by E+E Elektronik. The probe can be plugged into the host device based on the plug-and-play principle and thus extended to a sensor unit with analogue outputs and an optional display.

Posted by DA Editor Connect & Contact

Keep up to date with the latest news and
technical developments in Unmanned Systems.

Sign up to the UST weekly eBrief

By clicking "Sign me up" I consent to my personal information being processed for the purpose of sending me the 'eBrief' weekly e-newsletter. See our Website privacy policy.