Value Series PH850 Portable pH Meter with Temperature Probe Only

What the AI5590 Is — and What It Isn't

The AI5590 is the Apera PH850 meter body paired with a standalone temperature probe — no pH electrode in the box. That's intentional. It targets facilities that already own Apera LabSen electrodes, labs standardizing on the BNC connector ecosystem, or operations buying multiple meters while sharing specialized electrodes (purified-water, spear-tip, flat-surface) across workstations. If you need the full kit with the 201T-F combination electrode, that's a different SKU.

The PH850 meter itself is the same rugged platform used across Apera's entire 850 lineup: IP57 water resistance, a silicone rubber grip boot, a foldable bench stand, and a large backlit LCD that displays pH, temperature, calibration status icons, and a dedicated stability indicator simultaneously. It runs on three AAA batteries — no USB power dependency in the field.

Measurement Performance for Commercial Cultivation

The meter delivers ±0.01 pH accuracy across the full 0–14 pH range at 0.01 resolution — sufficient for the tight fertigation windows (typically 5.8–6.2 for soil/coco, 5.5–6.0 for rockwool) that licensed cannabis operators run. Automatic Temperature Compensation (ATC) is active whenever a temperature probe or compatible 3-in-1 electrode is connected; manual temperature compensation is available as a fallback when using a probe-less BNC electrode.

Calibration is 1–3 points, auto-recognizing NIST buffers at 1.68, 4.00, 7.00, 10.01, and 12.45 pH. After the second or third calibration point, the meter displays electrode slope — a direct read on electrode condition that tells you when to replace the probe before readings drift out of spec. A built-in self-diagnosis function flags out-of-range values and calibration errors with on-screen guidance rather than silent failure.

ORP measurement is supported in mV mode when an ORP probe (model 301Pt-C, sold separately) is connected via BNC. For operations tracking dissolved oxygen, oxidation potential, or post-treatment water quality, no second meter is required.

Build Quality and Fieldwork Practicality

IP57 means the meter is protected against dust ingress and can be submerged in up to 1 meter of water for 30 minutes — meaningful in a commercial grow environment where meter housings routinely get splashed, dropped in reservoirs, or set down on wet benches. The silicone rubber boot absorbs shock from general impact and provides grip when hands are wet.

The foldable stand on the base lets the PH850 function as a benchtop unit when left on a workstation for continuous spot-checking — useful in head-house environments where the meter sits between reservoir adjustments. The large LCD runs clear readouts of pH, temperature, and calibration icons simultaneously, reducing the chance of misreading under low-light conditions in flower rooms.

Power is three standard AAA batteries. No proprietary cells, no charging cables to manage in a wet room. Meter body dimensions are 86 × 196 × 33 mm at 335 g — easy single-hand operation. The BNC connector is fully compatible with Apera's LabSen Series of specialty electrodes, so the same meter body works across general water, purified water, wastewater, or high-temperature applications as electrode needs change.

Where This Unit Fits a Commercial Build

The AI5590 configuration makes sense in three specific scenarios. First: facilities that already have Apera 201T-F or LabSen combination electrodes in service and need additional meter bodies without redundant electrode costs. Second: operations assigning different electrodes to different rooms or water sources (RO line vs. fertigation reservoir vs. runoff collection) and want a single meter standard across the floor. Third: procurement teams spec-ing replacement meters while legacy probes are still within service life.

For new builds without any existing Apera electrode inventory, evaluate the full PH850 kit (with 201T-F electrode and buffer solutions included) before selecting the AI5590. The meter platform is identical; the only difference is what arrives in the case.

Warranty: 3 years on the instrument, 6 months on the temperature probe, both from delivery. Apera is based in Columbus, Ohio and has been producing water-analysis instruments since 1991. HSC supplies Apera instrumentation to licensed cannabis and hemp operators nationwide — request a quote for current lead time and volume pricing.