APERA INSTRUMENTS / PH8500-WW / AI5559

Open-junction measurement
for demanding water samples.

The PH8500-WW brings the LabSen 333 pH/temperature electrode to Apera’s portable PH8500 meter for wastewater, emulsions and suspensions. Its POM body, open junction and polymer reference are selected for aqueous samples that can foul a conventional junction. Integrated temperature sensing and wired USB data handling support a repeatable measurement routine, from sample collection through review. This is a liquid-sample configuration, not a penetration probe for solid material.

Choose AI5559 for its sample-facing electrode design, not a broader promise about every wastewater matrix. The supplied LabSen 333 is replacement SKU AI3133. Use the conservative current range of 0–13 pH and 0–80°C, distinct from the meter’s wider display capability. POM construction and an open junction do not eliminate cleaning, prevent every clog or establish universal chemical resistance. Match the method to the sample before relying on a number.

An open junction for complex liquids

The LabSen 333 uses an open junction with polymer reference electrolyte, a design intended to reduce junction-clogging problems in wastewater, emulsions and suspensions. Its Long-Life reference is part of the electrode construction, not a guaranteed service duration. Inspect the measuring end between samples and remove residue before it affects the next result. No particle-size limit, solids percentage or maximum viscosity is established for this kit.

Temperature sensing without another probe

A built-in NTC 30 kΩ temperature sensor connects through the black RCA lead, while the blue BNC lead carries pH. Both are used with the supplied PH8500 for temperature-compensated measurement. Automatic compensation addresses the electrode’s response; it does not make samples at different temperatures chemically identical. Check the displayed temperature and sample conditions, and do not infer full compatibility with another meter from a BNC socket alone.

Records that can move off the meter

The PH8500 offers 500 sets of memory with manual and interval recording, plus USB connection to PC-Link. Current Web PC-Link supports compatible desktop Chrome or Edge on Windows or Mac, CSV export and browser printing. Saving as PDF depends on the browser and operating system. New readings logged while connected go to software, not meter memory, so export before closing. The workflow is not Bluetooth, ZenTest or an immutable electronic audit trail.

Know exactly what is supplied.

Wastewater and effluent checks

Use the wastewater configuration for appropriate treatment and effluent samples within the probe’s pH, temperature and chemical limits. Establish a representative collection method and use consistent handling when comparing locations or treatment stages. The manufacturer identifies these applications, but that is not a blanket qualification for every industrial discharge. Check unusual contaminants and aggressive chemistry separately rather than treating the POM body as immunity from damage.

Emulsions and suspended material

The open junction is a purposeful choice for compatible emulsions and suspensions that tend to cause problems with regular electrodes. Keep the liquid representative without forcing the tip into settled solids or scraping it along the vessel. No numerical solids loading or particle-size allowance is specified. If the sample cannot freely surround the measuring end, reassess preparation and probe selection rather than assuming a direct measurement is valid.

Portable rounds and bench follow-up

A backlit LCD, folding stand and IP57 meter enclosure suit a portable station that can also rest on a bench. Use the same calibrated probe and consistent sample handling when moving between locations. Check the clock before logging, identify samples in the laboratory record and review readings after the round. The case helps organize the equipment; it does not replace careful transport of a wet-stored electrode or dry electrical connectors.

Representative liquid.
Clean junction. Stable result.

Connect the blue BNC pH lead and black RCA temperature lead to the PH8500. Twist off the storage bottle cap, remove the electrode and rinse it with distilled or deionized water. Perform at least a two-point calibration before measuring with a new electrode, using standards appropriate to the expected sample range. Keep clean portions of buffer separate from samples and rinse between them so carryover does not become part of the result.

Collect a representative liquid sample and immerse the sensing membrane and open junction without pressing the tip against the container or coarse particles. Avoid scraping, crushing or using the probe to break up solids. Allow the reading to stabilize, and note the sample temperature and relevant handling conditions. A guarded tip still contains a sensitive measuring surface. Open-junction construction is not an instruction to ignore deposits, unusual response or a sample that cannot adequately contact the sensor.

For routine readings, save only after checking stability and confirming the sample identity in your working record. For interval measurement, verify settings and memory availability before leaving the instrument to record. If connected to PC-Link, treat the computer session as the destination for new readings and export the results before closing it. Browser reports and editable CSV files support review, but do not by themselves provide validated laboratory records, authenticated signatures or guaranteed retention.

No reference refill.
Wet storage still matters.

The LabSen 333 polymer reference is nonrefillable. Do not add liquid inside the electrode or follow refill instructions intended for the LabSen 803. External storage is a different task: keep the probe in its storage bottle with 3M KCl solution, replacing that solution when contaminated or insufficient. The supplied probe’s storage bottle and cap are shown, but a separate bulk KCl bottle is not confirmed for the PH8500-WW kit.

Rinse thoroughly before and after each measurement, then return the electrode to wet storage and tighten the cap. Distilled or deionized water is appropriate for rinsing, not for long-term storage. Keep the BNC and RCA connectors clean and dry. Avoid strong acid, strong alkali and dehydrating liquids such as absolute ethanol. If the sample is unusually aggressive or persistent residue remains, review compatibility and the electrode-specific cleaning instructions before continuing the measurement series.

For tough contamination, the manual specifies Apera AI1166 cleaning solution for 30 minutes, followed by gentle cleaning with a soft brush and at least one hour in 3M KCl. Rinse and recalibrate before returning to use. These cleaning and replenishment supplies are not included unless expressly listed. Manufacturer limited coverage is three years for the meter and six months for the probe from delivery; wear, misuse, improper storage and other specified causes are excluded. The warranty is not a service-life prediction.

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.