APERA INSTRUMENTS / PH8500 / AI5520

Take the pH method with you.
Bring the readings back.

Build a portable routine for general-water pH testing with the PH8500, its supplied 201T-F pH/temperature electrode and USB data workflow. The backlit display brings the selected reading, temperature and measurement indicators together, while the fold-out stand lets the same instrument work beside a sample vessel at the bench. A carrying case keeps the core testing kit together between locations.

Choose AI5520 when pH is the primary measurement and the samples suit a general-water electrode. Choose PC8500 for pH plus conductivity, or EC8500 for conductivity-focused work. Within the pH family, PH8500-PW uses LabSen 803 for low-ionic water, PH8500-WW uses LabSen 333 for wastewater and suspensions, and PH8500-MS uses LabSen 243-6 for small samples. These are different electrode configurations, not extra probes in this box.

One electrode, two connections

The 201T-F combines the pH glass membrane, reference system and temperature sensor in one probe. Its blue BNC connection carries pH/mV and its black RCA connection carries temperature. The sealed gel KCl reference is nonrefillable, so routine care is external rinsing, cleaning and wet storage, not opening the probe to replenish electrolyte. The supplied probe supports automatic temperature compensation without a separate temperature probe.

Portable controls, useful feedback

The meter provides ±0.01 pH ±1 digit accuracy, selectable 0.1 or 0.01 pH resolution and a stability indicator to guide when a result is ready to record. Calibration review includes the latest offset, slope and date/time. Selectable stability criteria and optional automatic hold support a repeatable reading routine. IP57 housing and the fold-out stand suit movement between work areas; keep connectors clean, dry and appropriately protected.

Know where each reading is saved

Away from the computer, manual M+ saving and timed logging use the meter’s 500-set memory. USB PC-Link provides a computer workflow through desktop Chrome or Edge on Windows or Mac, with CSV export and browser printing. Crucially, new readings logged while connected go to PC-Link software instead of meter memory. Export and check the files before ending a session; a connected session is not a duplicate meter backup.

Know exactly what is supplied.

General-water checks

Use this base configuration for compatible aqueous samples where a conventional general-water pH electrode fits the method. Collect a representative sample, allow temperature to settle and use a consistent immersion and stabilization routine. The meter’s wider electronic range does not turn the supplied probe into a high-temperature or strongly caustic sensor.

Bench-to-site comparisons

Take the same instrument and calibration routine between sample locations and the laboratory. The portable format is useful when a fixed benchtop station would interrupt the work. Record sample identity separately alongside the exported results, and check the meter clock before logging so date and time remain meaningful to your own records.

Choosing a specialty kit

Very low-ionic water, fouling wastewater and tiny sample volumes call for different electrode decisions. The PW, WW and MS configurations address those distinct tasks; they do not simply add meter accuracy. For MS, the published 60 µL minimum depends on the included 6 mm semi-micro container. Do not apply that volume to this full-size 201T-F.

Calibrate for the sample.
Record after stabilization.

Connect both electrode plugs, remove the storage bottle and rinse the sensing end with distilled or deionized water. Shake away excess rinse water without rubbing the glass membrane. Set the intended buffer series and check the date, time and logging settings before starting a run. When fitting a new 201T-F, follow its instruction to perform a three-point calibration before relying on measurements.

Begin pH calibration with the neutral buffer for the selected series: pH 7.00 for USA or 6.86 for NIST. Use fresh portions and additional points appropriate to the expected samples. The kit supplies 50 mL each of pH 4.00, 7.00 and 10.01 buffer. Rinse between standards and samples, gently stir to release bubbles, and wait for the stability indicator before saving. Temperature compensation corrects electrode response, not every temperature-driven change in sample chemistry.

Decide whether the run belongs in meter memory or in a connected PC-Link session before collecting results. Timed logging uses a configured interval; manual saving suits selected stable readings. Review the latest calibration information with the data, export the CSV for spreadsheet work and use browser print when a report is needed. Verify the saved output before clearing memory or closing the browser. Keep your sample notes and file backups under your laboratory’s own procedure.

Read the meter.
Know what is held.

Use the physical controls for standalone measurement and calibration. The stable-reading indicator and HOLD help you read a result; a held display is not an onboard measurement-history logger for later upload.

Keep the connectors and battery compartment dry when changing parts. Follow the exact manual for key sequences, battery orientation and cap sealing. Screen values in photographs are illustrative, not test results or a promise of compatibility with another sensing head.

Build a local record.
Keep the transfer workflow clear.

Each 8500 meter can measure and calibrate without a computer. It can retain up to 500 data sets, including date, time, measured value, unit, temperature and the last calibration record. M+ supports manual saving after stability; timed logging can be set from one minute through 99 hours 59 minutes. Deleting stored values cannot be undone.

For computer work, use the meter USB connection with the current Web PC-Link workflow on a desktop Chrome or Edge browser under Windows or Mac. The tool supports CSV output and browser-print reporting. Do not assume Firefox compatibility, a native Excel/PDF export format, an immutable audit trail, electronic signatures or regulatory validation.

When connected to PC-Link, new records go to the software rather than to the meter memory. Save and export important records before closing the browser. USB logging does not guarantee automatic backup, permanent retention or protection from user deletion. Keep the exact meter, configured probe and sample method with any record.