APERA INSTRUMENTS / PH950 / AI5620

Everyday pH precision.
A more organized bench.

PH950 brings pH measurement, sample stirring and electrode positioning into one benchtop kit. The included LabSen 211 glass pH electrode works alongside a separate MP500 temperature probe. The 606 TestBench combines a flexible holder, solution organizers and magnetic stirring, keeping calibration and routine liquid testing close at hand.

Choose PH950 for routine laboratory pH with 0.01 pH resolution and USB record transfer. Its instrument accuracy is ±0.01 pH ±1 digit. This is a pH/mV/temperature system, not a conductivity meter or an automated titrator.

Two probes, distinct jobs

LabSen 211 measures pH through a hemispherical glass membrane and ceramic junction. Its refillable Long-Life reference supports compatible general aqueous and TRIS-buffer work. The separate stainless-steel MP500 supplies temperature for automatic compensation; the pH electrode has no built-in temperature sensor.

A controlled mixing routine

The included 606 supports gentle mixing and repeatable electrode positioning. Adjust stirring from the meter. Hold RPM for about three seconds to save a speed; short-press to recall or switch. Keep the rotating bead clear of both probes. The workstation does not heat or regulate sample temperature.

Calibration without guesswork

Select USA, NIST or CH standard buffers and calibrate at one to three points. Custom buffers are a separate one- or two-point mode, not a three-point custom calibration. Use fresh portions and choose points appropriate to the intended sample range.

Know what this configuration supplies.

Routine laboratory liquids

Compare compatible aqueous samples in teaching, preparation and quality-control work. Standardize vessel, immersion depth, stirring and measurement temperature before comparing batches.

Water and process samples

Measure suitable collected water samples at the bench. Difficult low-conductivity, dirty or highly viscous samples may require a different electrode or a defined preparation method.

Buffer preparation and TRIS

Check compatible buffer solutions with a maintained Long-Life reference. TRIS suitability is not universal resistance to every protein, solvent or aggressive formulation.

Connect separately.
Calibrate deliberately.

Connect LabSen 211 to the BNC pH/mV input and MP500 to the RCA temperature input. The temperature channel uses a 30 kΩ NTC sensor. Remove the electrode storage bottle, rinse the sensing end and open the refill plug before calibration or measurement. Keep connectors dry.

Start standard calibration with the neutral buffer in the chosen series, then add appropriate acidic or alkaline points, up to three in total. Rinse between solutions and never return used buffer to its bottle. For custom buffers, enter their values and follow the same-temperature calibration and measurement procedure.

Immerse both probes in the sample without striking the vessel or stir bead. Allow the temperature and reading to stabilize before recording pH. Automatic compensation corrects electrode response, not every sample’s chemical temperature dependence. Keep this supplied electrode within 0 to 14 pH and a conservative 0 to 100°C working range.

3M KCl for refill.
3M KCl for storage.

Check the reference electrolyte level regularly. When it falls to about half the electrode height, refill with the specified 3M KCl through the refill opening. The blue inner sensing gel is not the refill liquid. This Long-Life electrode does not use Protelyte.

After testing, rinse away residue, close the refill plug and return the electrode to its storage bottle with 3M KCl soaking solution. Replace contaminated solution. Distilled or deionized water is for rinsing, not long-term storage; protect the glass tip from drying and impact.

If response becomes slow, inspect for deposits and follow the electrode manual’s appropriate cleaning and reconditioning procedure before recalibrating. Do not scrape the glass membrane. Keep the meter and electrical connections away from spills, and disconnect power before cleaning the workstation.

A stable reading is the start of the record.

Use the physical meter controls for measurement and calibration, then record or save a stable result. A held display and a stored record are different functions. Screen values in photographs are illustrative, not measurements of your sample.

Use calibration solutions and settings appropriate to the parameter and fitted electrode. Temperature compensation does not make different sample temperatures, preparation methods or chemistry equivalent. Follow the model-specific meter and electrode instructions before extending the method to a new sample.

USB records, with software boundaries made clear.

PH950 supports manual and timed logging with date/time records and access to the last calibration information. Current feature copy and the operating manual specify 200 sets, while an older specification block says 100. Confirm capacity for the supplied unit if it is critical to your workflow.

USB communication with legacy PC-Link 950 desktop software is documented, and a USB cable and software flash drive are included. The manual distinguishes downloading stored readings from collecting new readings while connected; readings uploaded during connected logging are not also saved in the meter.

The current product page links Web PC-Link 9500, but that application identifies a 9500-series protocol. PH950 browser compatibility is not confirmed. Do not depend on its CSV, JSON or browser-print features for this model without confirmation. Check desktop compatibility and save exported records before closing the session.