Accurate and reliable measurements for ORP processes; completely eliminate ground-loop and noise issues.


The advanced “isolated” circuitry of the 720 Series II ORP Monitor/ controllers guarantees accurate and reliable measurements — completely eliminating ground-loop and noise issues.

The unique sensor preamp allows for longer distances between the sensor and the Monitor/controller without the loss of accuracy or reliability.

All Myron L® Monitor/controllers feature a highly refined and precise Temperature Compensation circuit. This feature perfectly matches the NERNST equation correcting the displayed reading to 25°C. The TC may be disabled to conform to USP requirements.


  • Built-in electronic calibration allows for fast quality checks without buffers. (Note: for maximum system accuracy buffers are recommended).
  • A push-to-test button makes set point checks easy, while the internal alarm set discourages unauthorized adjustments.
  • Standard on all controller models is a heavy-duty 10 amp output relay, operating on either increasing or decreasing readings. Bright green/red LEDs indicate above/below set point readings.
  • All 720 Series II models feature an IP65/ NEMA 4X water resistant and corrosion proof rated enclosure. Compact in size, at 152 x 122 mm/6 x 4.8 in., the 720 Series II models are suitable for panel, bench or surface mounting.

Model NumberDescription
728IIMonitor/Controller, ORP, DIG
728II-4AMonitor/Controller, ORP, DIG, 4-20mA OTPT
728II-4A-PCMonitor/Controller, ORP, DIG, 4-20mA OTPT, PWR CORD
728II-PAMonitor/Controller, ORP, DIG, ~70dB ALRM
728II-SCMonitor/Controller, ORP, DIG, 2ND ALARM MOD
728II-SC-PCMonitor/Controller, ORP, DIG, 2ND ALARM MOD, PWR CORD
728OBMonitor/Controller, ORP, CIRCUIT BRD, DIG
729II-4AMonitor Only, ORP, DIG, 4-20 mA OTPT
729OBMonitor Only, ORP, CIRCUIT BRD, DIG