Starting at $771.00

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  • Fast, accurate, & stable measurement
  • Rugged, versatile design
  • Long lasting rebuildable reference
  • Quick connect cable or integral cable
  • VP8 Connector Cable in multiple lengths
  • Operating temp: 41 to 248°F (5 to 120°C)

The 3500P and 3500VP are the foundation of the Rosemount Analytical PERpH-X™ high performance pH / ORP sensor offering. The 3500P sensors incorporate several design innovations that prolong the life of the sensor in difficult applications. These include the improved durability of the pH glass electrode, the increased stability of the reference electrode and the overall reliability of the mechanical design. The resulting sensors live longer, respond faster and drift less thereby minimizing maintenance and lowering the total cost of ownership.

The ACCUGLASS™ pH glass electrode provides exceptional resistance to thermal and caustic degradation. This translates to less breakage from thermal stress or shock and improved speed of response for fast and accurate calibrations even after months of service.

The PERpH-X™ sensors feature an enhanced double junction reference electrode that excels in harsh applications. The specially designed porous Teflon® liquid junction has a large surface area to maintain a steady reference signal in dirty fouling applications. The large surface area and high porosity also minimize junction potentials leading to accurate measurements without standardization. The porous Teflon® reference junction is easily replaced in the event that it becomes fouled or plugged.

The 3500P/3500VP pH / ORP sensors accomplish measurement in difficult applications with the use of a molded Ryton™ body. The chemically resistant construction is further enhanced by the choice of EPDM, Viton® or Kalrez orings. The versatile 1" MNPT body design also incorporates front and rear facing threads to provide a wide range of mounting options. The PERpH-X™ high performance pH / ORP sensors are designed to provide superior performance in the most chemically aggressive dirty fouling applications.


Rosemount Analytical Connector Cable
Lengths of cable with VP8 sensor connectors
In Stock
Rosemount Analytical 11-conductor Extension Cable


Please consider these optional accessories.

Rosemount Analytical pH Buffer Solutions
pH buffers for the precision calibration of pH meters
Rosemount Analytical Replacement O-ring Kits
Replacement o-rings for Teflon junction
Rosemount Analytical Refill Kits
30 cc Syringe (4-5 refills per syringe)
Rosemount Analytical Porous Teflon Reference Junction Kits
Porous teflon reference junction kit
Rosemount Analytical Solution Kits
Contain everything needed to rebuild the reference electrode
Rosemount Analytical 23555-00 Junction Box
Compatible with models 54, 5081, 1055 & Xmt preamplifiers
Rosemount Analytical NPT Process Connection
CPVC flow through tee with 1.5in NPT process connection
Rosemount Analytical Tee Flow Through Mounting Assembly
Tee Flow Through Mounting Assembly with 2"PVC with 3/4, 1", or 1 1/2 NPT
Rosemount Analytical 99CC Calibration Certificate
One certificate per lot at standard factory ranges only, includes the model, serial and/or tag numbers (does not include actual test data)
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: