AMT620 Lab pH Meter

AMTAST Lab pH Meter

AMT620 Lab Benchtop pH Meter

Keywords: AMT620, lab pH meter, benchtop pH tester, ATC/MTC, 3-point calibration

High-accuracy benchtop pH/mV meter with 2–3 point calibration, ATC/MTC temperature compensation, self-diagnostics and GLP data storage for research and QC laboratories.

The AMT620 is a precision benchtop pH meter built for research, production and QA/QC laboratories. It measures pH (0.00–14.00; up to -2.00–16.00 pH on the 620Pro), mV (±2000 mV) and temperature (-5.0 to 105.0 °C) with 0.01 pH / 1 mV / 0.1 °C resolution and ≤0.01 pH / 3 h long-term stability. A microprocessor-driven design supports up to 3-point calibration, automatic or manual temperature compensation (ATC/MTC), and self-diagnostics to flag electrode slope, zero offset or out-of-range readings.

The instrument ships with a custom segment LCD, an electrode holder and a pH combination electrode. The 620Pro variant adds RS-232 PC connectivity, auto and timing data storage (up to 1024 datasets with date/time), and extended buffer libraries including NIST, Mettler-Toledo and MERCK. With its ABS housing (200 × 160 × 65 mm, 0.65 kg) and DC 9 V adapter, the AMT620 sits neatly on any lab bench.

Key Features

1.  High-Resolution pH / mV / Temperature — 0.01 pH, 1 mV and 0.1 °C resolution with ≤0.01 pH / 3 h long-term stability.

2.  2- or 3-Point Calibration — Calibrate with up to three buffer points from NIST, Mettler-Toledo or MERCK libraries (620Pro).

3.  ATC and MTC Temperature Compensation — Compatible with external temperature probes for ATC, plus manual entry for MTC.

4.  Self-Diagnostics (Err1–Err9) — On-screen error codes alert users to electrode damage, buffer mismatch, slope drift or memory full.

5.  GLP Data Storage (620Pro) — Up to 1024 measurements with value, unit, temperature, ATC/MTC status, date and time.

6.  RS-232 PC Communication (620Pro) — Stream measurements directly to a PC for monitoring, archiving or further analysis.

7.  Sensor Performance Display — Real-time icons show electrode response (good / acceptable / replace).

8.  Auto Endpoint Detection — Locks readings when stable so you can record results with confidence.

How to Use

1.  Connect and Power On — Attach the pH combination electrode to the BNC socket, plug the DC 9 V adapter into a mains outlet and switch on via the front panel.

2.  Prepare the Electrode — Remove the storage cap, rinse with distilled water, and verify the reference junction is immersed in the sample to be tested.

3.  Select Buffer Set — Press and hold MODE for 1.5 s, then choose a buffer library (b1 standard, b2 Mettler-Toledo, b3 NIST, b4 MERCK on the 620Pro) to match your reagents.

4.  Calibrate — Rinse the electrode, immerse in pH 7 buffer first (then pH 4 and pH 10 / 9.18 as needed), and press CAL. The meter auto-identifies each point and stores the slope and offset.

5.  Measure the Sample — Rinse and immerse the electrode in the sample, set the temperature (ATC or MTC), and read the stable value on the LCD or transfer it to PC via RS-232 (620Pro).

6.  Save / Review Data — Use the M+/∧ key to store readings manually, or enable auto / timing storage (620Pro) and review the log with the RM/∨ key.

Technical Specifications

Model	AMT620 (620Pro)
pH Range	0.00 – 14.00 pH (-2.00 – 16.00 pH for 620Pro)
mV Range	±2000 mV (±1999.9 mV on 620Pro)
Temperature Range	-5.0 – 105.0 °C
Resolution	0.01 pH / 1 mV / 0.1 °C
Accuracy	≤0.01 pH / ≤0.1 % FS mV / ≤0.5 °C
Stability	≤0.01 pH / 3 h
Input Impedance	≥10¹² Ω
Calibration Points	Up to 3 points (620: b1 standard; 620Pro: NIST / Mettler-Toledo / MERCK libraries)
Buffer Sets (620)	pH 1.68 / 4.00 / 7.00 / 10.01
Buffer Sets (620Pro)	b1 standard, b2 Mettler-Toledo, b3 NIST, b4 MERCK
Temperature Compensation	ATC and MTC, 0.0 – 100.0 °C
Memory	620: 64 sets – 620Pro: 1024 sets with date / time and ATC/MTC status
Communication	RS-232 (620Pro only)
Self-Diagnostics	Err1 – Err9 (electrode, zero, slope, buffer, memory)
Environment	5 – 35 °C, ≤85 % RH
Power Supply	DC 9 V adapter (AC mains input)
Dimensions	200 × 160 × 65 mm
Weight	0.65 kg

Applications

1.  Research institutes — chemistry, biology, environmental science and clinical laboratories

2.  Industrial QC labs — water treatment, effluent monitoring and process chemistry

3.  Production lines — pharmaceutical manufacturing, food and beverage processing

4.  Petrochemical and metallurgy — drilling fluids, plating baths and metal-finishing solutions

5.  Education and training — university analytical chemistry and instrument labs

6.  Regulatory compliance testing — GLP / ISO 17025 workflows with stored audit-trail data

Spare Parts

Optional accessories available for separate purchase — select any combination based on your testing needs:

1.  pH combination electrode (BNC) — replacement or spare glass-body electrode

2.  Temperature probe — for ATC (auto temperature compensation)

3.  RS-232 cable and PC software kit (620Pro) — for data transfer to PC

4.  Buffer solution packs — NIST / Mettler-Toledo / MERCK libraries for periodic calibration

5.  Electrode holder assembly (replacement / spare)

6.  DC 9 V power adapter (replacement / spare)