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Ohaus Pen Meter ST20M-C Portable Electrochemical Meter for pH, Conductivity, and Salinity

UsedOhausConductivity metersUnited States

€127.39excl. VAT

In stock

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Meter Type
Conductivity; pH; Salinity
Measurement Range
0.0 – 99.0 °C; 0.00 – 14 pH; 0.00 – 19.99 ms/cm; 0.0 – 10.0 ppt
Accuracy
± 0.05 pH / ± 0.5 °C; ±2.0 % F.S.
Measurement Resolution
0.01 pH; 0.01ms/cm; 0.1 ppt; 0.1 °C
ATC
Yes
All 24 specifications
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Specifications 24

Brands
Ohaus
New/Used
Used
Meter Type
Conductivity; pH; Salinity
Measurement Range
0.0 – 99.0 °C; 0.00 – 14 pH; 0.00 – 19.99 ms/cm; 0.0 – 10.0 ppt
Accuracy
± 0.05 pH / ± 0.5 °C; ±2.0 % F.S.
Measurement Resolution
0.01 pH; 0.01ms/cm; 0.1 ppt; 0.1 °C
ATC
Yes
Temperature Compensation
Not Applicable
Automatic Shutdown
Yes, After 6 minutes of non-use
Battery Life
100 Hours with Disposable Batteries
Calibration
3 Point
Conductivity accuracy (±)
2 %
Conductivity measuring range
0.00 – 19.99 mS/cm
Dimensions (LxHxW)
7.28 in x 1.5 in x 1.77 in (185 mm x 38 mm x 45 mm)
Net Weight
3.88 oz (110 g)
Number of Buttons
3
pH accuracy (±)
0.05
pH measuring range
0
Power
4 AG13 Batteries (Included)
Protection Rating
IP67
Temperature Display
Yes
Temperature Sensor
50 KΩ NTC
Working Environment
50°F – 104°F, 85%RH, non-condensing (10°C – 40°C, 85%RH, non-condensing)
Wrist Strap
Yes

Product description

Portable pen meter measuring pH, conductivity, salinity, and temperature with IP67 waterproof rating and 3-point calibration.

Ohaus Pen Meter ST20M-C Model #30393200

  • Measurement capabilities: Conductivity, pH, Salinity, and Temperature
  • Ranges:
  • Temperature: 0.0 – 99.0 °C
  • pH: 0.00 – 14 pH
  • Conductivity: 0.00 – 19.99 mS/cm
  • Salinity: 0.0 – 10.0 ppt
  • Accuracy:
  • pH: ±0.05
  • Temperature: ±0.5 °C
  • Conductivity: ±2.0 % Full Scale
  • Resolution:
  • pH: 0.01
  • Conductivity: 0.01 mS/cm
  • Salinity: 0.1 ppt
  • Temperature: 0.1 °C
  • Temperature compensation: Automatic Temperature Compensation (ATC) enabled, using 50 KΩ NTC sensor
  • Calibration: 3-point calibration for accuracy
  • Design: Durable plastic housing with IP67 waterproof rating, protective sensor cap, wrist strap, and automatic shutdown after 6 minutes of inactivity
  • Power: Operates with 4 AG13 disposable batteries, providing approximately 100 hours of battery life
  • Physical dimensions: 185 mm x 38 mm x 45 mm (L x H x W)
  • Weight: 110 g (3.88 oz)
  • User interface: 3 buttons for simplified operation
  • Operating conditions: Ambient temperature 10°C – 40°C, up to 85% relative humidity, non-condensing environments
  • Additional features: Temperature display function and rugged design suitable for field and laboratory use

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Frequently asked questions

How long does laboratory equipment typically last?

With a service contract, ten to fifteen years is normal for most benchtop instruments. Detectors and pumps are the parts that wear first.

Can I get service for older equipment?

Often, yes. Verified suppliers frequently work with service partners converting the instrument. If applicable, we can list servicing options alongside the offer.

Where can I buy parts?

Ask a scientist through the request button. Parts are often available even when the instrument itself is discontinued.

What is the typical lead time for refurbished equipment?

Two to six weeks, depending on refurbishment scope and whether calibration is included.

Does laboratory equipment ship internationally?

We ship to 38 countries. Crating and customs handling are quoted with the instrument.

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Last updated 22 October 2026