Rosemount Analytical Model 385+ pH / ORP Sensor
Starting at $539.00

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  • Range: 0-14 pH
  • Disposable Tefzel and titanium design
  • Platinum ORP electrode
  • ORP: ±1500 mV
  • Maximum Process Pressure: 100 psig
  • Long-life

The Rosemount Analytical Triple-junction Model 385+ is now offered with SMART capabilities. SMART option becomes enabled when used with the Model 1056, 1057 Analyzer and on 6081P wireless transmitter. The pH-loop capabilities include auto-recognition of the SMART sensor, automatic upload of calibration data and associated time stamp, historical recording of pH diagnostics (slope, offset, reference impedance, glass impedance). This trending data allows technicians to predict frequency of maintenance and estimate sensor life for a particular process condition. Additional SMART features include factory calibration, resetting SMART sensor calibration data with user menus without power cycling, and manufacturing information.

The Rosemount Model 385+ Sensor is designed to provide advanced sensor diagnostics available with the Models 54e,1055, 1056 or 1057 pH/ORP Analyzer, or Models 81, 3081, 4081, 5081, 6081 or Xmt Transmitter. (Please refer to the instrument's product data sheet for complete information.) These advanced sensor diagnostics provide preventative maintenance by notifying the operator to replace an aged sensor or clean a fouled sensor for continuous optimum performance.

The Model 385+ Sensor measures the pH or ORP (Oxidation Reduction Potential) of aqueous solutions in pipelines, open tanks, or ponds. It is suitable for applications where a low cost, industrial, disposable sensor is required. The combination electrode features a peripheral ceramic junction. The triple junction reference cell provides longer life in processes containing sugar, ammonia, chlorides, sulfides or other poisoning ions. The Model 385+ body is constructed of molded, chemically resistant Tefzel in two standard body versions.

The retraction version is housed in a titanium tube, with a plug-in style surface mount preamplifier in a weatherproof junction box. It is designed for use with a standard 1-1/2 in. ball valve assembly for process mounting where a separate sample stream is difficult or impossible to provide. The entire installation process is accomplished without line depressurization and minimal process fluid loss. Following sensor removal from the ball valve, maintenance and replacement is easy.

The insertion/submersion version has two body configurations: 25 ft (7.6 m) integral cable and preamplifier; 15 ft (4.5m) integral cable for use with remote preamplifier.

The Model 385+ pH/ORP Sensor: Standard features include a Tefzel sensor body with a triple junction gel filled reference electrode and automatic temperature compensator housed in a titanium tube. The retractable version comes with a weatherproof junction box, a process connector, and preamplifier. The insertion/submersion version has two optional body configurations: integral SMART preamplifier (-03) option. The SMART is standard preamp option. It is offered with 25 ft (7.6 m) integral cable. A conventional Model 385+ is offered with 15 ft (4.5 m) integral cable for use with remote preamplifier if the distance to the instrument exceeds 15ft. The 385+ is designed to be used with the Models 54e,1055, 1056 or 1057 pH/ORP Analyzer, or Models 81, 3081, 4081, 5081, 6081 or Xmt pH/ORP Transmitter.


Rosemount Analytical 11-conductor Extension Cable

Mounting Bracket


Please consider these optional accessories.

Rosemount Analytical 23166 Connector
1 x 1in with o-ring groove, in 316 SS or titanium
Rosemount Analytical pH Buffer Solutions
pH buffers for the precision calibration of pH meters
Rosemount Analytical Ball Valve Assembly
Ball valve assembly in 316 SS
Rosemount Analytical 9510066 Process Connector
Process Connector, Nylon, Submersion. 1" MNPT
Rosemount Analytical 23550-00 Junction Box Remote
Rosemount Analytical 23555-00 Junction Box
Compatible with models 54, 5081, 1055 & Xmt preamplifiers
Rosemount Analytical Electronic Calibration
Certificate for specific unit, includes model, serial and/or tag numbers, test standards, NIST report numbers, & the actual test data
Rosemount Analytical Certificate of Origin
Original certificate of origin with chamber of commerce stamp


This product can be used in the following applications: