52k+ listingsShips to NLResponse within one hour+31 73 711 4717info@questpair.com

Ohaus ST3100M-B Benchtop Conductivity and pH Meter with Temperature Compensation

UsedOhausConductivity metersUnited States

Price on request

In stock

Can't find what you're looking for?

Measurement Range
00.0 μS/cm – 199.9 mS/cm; -5 °C – 110 °C; -2.00 – 20.00 pH; -1999 – 1999 mV; 0-20 MΩ•cm
Accuracy
± 0.5 % F.S.; ±0.01 pH; ±0.3 °C; ±1 mV
Measurement Resolution
0.01 μS/cm; 0.1 °C; 0.01 pH; 1 mV; 0.01 Ω•cm
Display
LCD, backlight
Accuracy ± (mV)
1 mV
All 25 specifications
  • Ships to NL
  • Response within 1 hour
  • Warranty available. Buy without worry
  • Support from a scientist

Specifications 25

Brands
Ohaus
New/Used
Used
Measurement Range
00.0 μS/cm – 199.9 mS/cm; -5 °C – 110 °C; -2.00 – 20.00 pH; -1999 – 1999 mV; 0-20 MΩ•cm
Accuracy
± 0.5 % F.S.; ±0.01 pH; ±0.3 °C; ±1 mV
Measurement Resolution
0.01 μS/cm; 0.1 °C; 0.01 pH; 1 mV; 0.01 Ω•cm
Display
LCD, backlight
Accuracy ± (mV)
1 mV
Accuracy ± (Temperature)
0.3 °C
Battery Life
Not Applicable
Conductivity accuracy (±)
0.5 %
Conductivity measuring range
0.0 – 199.9 µS/cm
Dimensions (HxLxW)
3.07 in x 6.89 in x 8.66 in (78 mm x 175 mm x 220 mm)
In-use cover
Included
Measurement Range (Temperature)
-5 °C – 110 °C
Net Weight
2.09 lb (0.95 kg)
pH accuracy (±)
0.01
pH measuring range
-2 – 20
pH resolution
0.01
Power
100 - 240 V
Resolution Cond. (Variable)
0.01 – 200
Resolution (Voltage)
1 mV
Temperature Compensation
Automatic
Temperature Resolution
0.1 °C
Temperature Sensor
30 KΩ NTC
Working Environment
14°F – 104°F, 85%RH, non-condensing (-5°C – 40°C, 85%RH, non-condensing)

Product description

Precision benchtop meter measuring conductivity, pH, mV, and temperature with auto compensation and data memory.

  • Measurement Ranges:
  • Conductivity: 0.0 μS/cm – 199.9 mS/cm
  • pH: -2.00 to 20.00
  • Voltage (mV): -1999 to 1999 mV
  • Resistivity: 0–20 MΩ·cm
  • Temperature: -5 °C to 110 °C (14 °F to 104 °F)
  • Accuracy:
  • Conductivity: ±0.5 % F.S.
  • pH: ±0.01 pH
  • Temperature: ±0.3 °C
  • Voltage: ±1 mV
  • Resolution:
  • Conductivity: 0.01 μS/cm
  • pH: 0.01
  • Temperature: 0.1 °C
  • Voltage: 1 mV
  • Resistivity: 0.01 Ω·cm
  • Display: Large backlit LCD for optimal viewing
  • Features:
  • Auto temperature compensation
  • Auto buffer recognition with six pH buffer groups
  • Five conductivity standard references
  • Automatic/manual endpoint detection
  • Adjustable electrode holder
  • Memory and Connectivity:
  • Stores up to 99 pH and conductivity measurements
  • RS232 interface for connection to external devices/printers
  • Power Supply: 100 – 240 V input
  • Physical Specs:
  • Dimensions: 78 mm x 175 mm x 220 mm (HxLxW)
  • Weight: 0.95 kg (2.09 lb)
  • Includes protective in-use cover
  • Temperature Sensor: 30 KΩ NTC
  • Operating Environment: 14°F – 104°F, 85% RH non-condensing (–5°C – 40°C)

This model provides reliable, multifunctional measurement of conductivity, pH, temperature, and mV suitable for laboratory applications requiring precise electrochemical analysis.

Why Questpair exists

Lab equipment markets are fragmented. Buyers spend weeks calling distributors, comparing quotes, and verifying supplier reliability. Sellers struggle to reach global research labs.

We built Questpair to fix this. Every supplier on the platform is verified before listing. Every quote you receive comes from a real, vetted seller. AI prepares your case in minutes, then a real specialist takes over.

We're an independent team based in The Netherlands, working with research labs and procurement teams across Europe and worldwide.

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.

Reply in one hour

Can't find the exact configuration?

Tell us what you need and a scientist finds it for you, usually within the hour.

Last updated 9 November 2026