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HP125 Series Multi-Sense Humidity Probe

Product Description

The HP125 Multi-Sense Humidity Probe is a cost effective, easy to use solution to many industrial and laboratory measurement and control applications. The HP125 probe exploits the latest advancements in polymer humidity sensing technology and compact electronic circuitry. It is designed to continuously measure up to 4 measurement parameters using a single intelligent sensor tip including RH%, calculated Dew Point, Temperature and either Absolute Pressure or Barometric Pressure!


The Smart Sensor Tip carries all configuration information and calibration data and automatically downloads to the HP probe once connected! Easily replaced, the Smart Sensor Tip can be replaced in seconds. Upon installation into the probe, it gets recognized and automatically synchronizes with the main software within the HP125 probe. This means that you have the option of quick turn-around for annual calibrations! No need to take the probe out of service for weeks for shipment and calibration off-site. Simply replace the old Sensor Tip with a new one! Each new tip comes with a NIST traceable calibration certificate for your records.


The HP125 probe provides 0-10VDC analog voltage outputs plus an RS-232 serial interface. The RS-232 offers reporting functions only. Each probe is configured with a smart sensor tip. The sensor tip is protected by a sintered metal filter cartridge. Both the filter and the sensor tip are replaceable. The probe may be directly inserted into process measurement points or may be coupled with a variety of application oriented sampling accessories for very flexible installation opportunities.

The probe may be used Stand-Alone or in combination with the HP125-DCM (Display Control Module) or the SENTRY series of Compressed Gas Alarm Modules. The probe comes with wire leads (labeled) for respective analog output and power inputs (25VDC Power).



• LDP option: measure dew point down to -60C

• Probe Configurations:

HP125 : RH / Temperature / Calculated Dew Point

HPP125 : Pressure / RH / Temperature / Calculated Dew Point

HPB125 : Barometric Pressure / RH / Temperature / Cal. Dew Point

• Display Control Module:

Provides local display of measured parameters and operating status

(2) adjustable relay alarms

(2) configurable 4-20 mA outputs

Bi-directional RS-232 Serial Interface

Standard power: 24 VDC, optional VAC power adapter


• CAM compressed air module: Sample chamber for probe. Provides sample flow to sensor probe and includes a ball valve to isolate the probe from the pressurized source during service. 3/4 inch NPT Female pipe threaded port to compressed air system take-off point

• Pipe Flange: For Probe insertion to 4 inch process flange; available in SS or PVC

• Serial Output Interface Cable: connects PC or to SENTRY, available for changing factory settings

• Uni-Strut Surface Mount adapter

• Surface Wall Mount


The HP125 control module offers many standard features including:

• Replaceable Smart Sensor Tip

• Analog Voltage Output (0-10VDC) for each measured parameter

• RS-232 Serial Interface for reporting function

• Replaceable Sintered Filter Element protects the sensor

• 24VDC Power Input


Common Applications of the HP125:

HVAC Duct Systems

Purged Atmosphere: Glove Box

Environmental Chambers

Isolation Chambers: PHARMA

Engine Testing: Air Intake& Exhaust

Modified Atmosphere Packaging

SEMICON: Furnace/ Lithography

Medical Packaging

Dryer Efficiency

Pharmaceutical Testing

Biologics & Cell Culture

Fluidized Beds

Food Storage / Packaging

Clean Rooms & Data Centers


  • Air Separators
  • Atmospheric Sciences
  • Automotive
  • Compressed Air
  • Food and Beverage
  • Furnace
  • Government Agencies
  • HVAC
  • Medical Gas
  • Metrology
  • Pharmaceuticals
  • Plastics
  • Power and Energy
  • Semiconductor
  • General Purpose
  • R&D Test & Measurement
  • Dynamometers
  • Engine Test Cells