Benchtop pH / mV Meter

AMT620 Lab Benchtop pH Meter

Keywords: AMT620, lab pH meter, benchtop pH meter, pH mV meter, ATC MTC pH meter

Benchtop pH/mV meter with 1/2/3-point calibration, automatic or manual temperature compensation, and 1,024-record data logging.

Model AMT620 is a microprocessor-controlled benchtop pH/mV meter for aqueous solutions in institutional, industrial and production laboratories. It reads pH from 0.00 to 14.00 pH and ORP/electrode potential over ±1999.9 mV, with sample temperature from −5.0 to 105.0 °C. Resolution is 0.01 pH, 1 mV and 0.1 °C, and pH accuracy is ≤ 0.01 pH.

Temperature compensation can run automatically (ATC) or be keyed in manually (MTC) — the display always tells you which mode is active. Four buffer sets are built in (Standard, Mettler-Toledo, NIST and MERCK) so the meter recognises whichever buffers your lab already stocks. After each calibration the meter judges the electrode itself and shows a smiling, neutral or frowning face, so you know whether to keep or replace the sensor. Up to 1,024 readings can be stored manually, automatically or on a 1–60 minute timer, then recalled on screen or streamed to a PC over the RS232 port.

Key Features

1.  Wide measuring range — 0.00–14.00 pH, ±1999.9 mV and −5.0–105.0 °C, with 0.01 pH / 1 mV / 0.1 °C resolution.

2.  1 / 2 / 3-point calibration — one point adjusts the zero offset, two points correct offset and slope, three points also compensate non-linearity across a wide pH span.

3.  ATC and MTC temperature compensation — automatic measurement (0.0–100.0 °C) or manual entry; accuracy ≤ 0.5 °C.

4.  Four selectable buffer sets — b1 Standard (1.68/4.00/7.00/10.01), b2 Mettler-Toledo (2.00/4.01/7.00/9.21), b3 NIST (1.68/4.01/6.87/9.18) and b4 MERCK (2.00/4.00/7.00/9.00/12.00).

5.  Electrode self-diagnosis — after calibration the LCD shows a smiling, neutral or frowning face together with the Offset and Slope values, plus 9 error codes (Err1–Err9) for fast troubleshooting.

6.  1,024-record memory — manual storage, automatic storage of every stable reading, or timed logging at 1–60 minute intervals; each record carries value, temperature, ATC/MTC status, date and time.

7.  RS232 output — connect to a PC with the companion software and readings transfer straight to the computer instead of internal memory.

8.  Six-key operation — ON/OFF, MODE, CAL, M+/∧, RM/∨ and READ; a long press of READ toggles the auto ending-point function, a long press of MODE opens the P1–P5 parameter menu.

How to Use

1.  Set up — fit the electrode holder arm on the base, plug the pH combination electrode and the DC9V adapter into the rear panel. As soon as the adapter is powered the meter enters standby (hold) mode.

2.  Select the buffer set — hold MODE to enter the parameter menu and set P2 to the buffer set (b1–b4) that matches the buffers you are using.

3.  Calibrate — press CAL, rinse the electrode and immerse it in the first buffer. The meter recognises the buffer value automatically. Continue through the 2nd and 3rd buffers if you need higher precision, or press READ to stop and return to measurement.

4.  Measure — rinse the electrode with distilled water and immerse it in the sample. Shake the vessel gently for a few minutes, then short-press READ. With auto ending-point on, the “/A” icon appears and the value is held when stable; with it off, the “Γ” icon appears and measurement continues.

5.  Switch to mV — press MODE to move between pH and mV measurement; the rinsing and reading procedure is identical.

6.  Store & recall — press M+ once the reading is stable to store it, short-press RM/∨ to recall the last record, or long-press RM/∨ to clear all memory (the display flashes “CLr.”).

Technical Specifications

Applications

1.  Routine pH and mV measurement of aqueous solutions in institutional, industrial and production laboratories

2.  Quality control and incoming inspection of liquid raw materials and finished products

3.  Water treatment, wastewater and environmental water testing

4.  Food and beverage analysis, including acidity and fermentation monitoring

5.  Chemistry teaching and research labs requiring documented readings

Spare Parts

1.  pH combination electrode (BNC)

2.  Electrode holder set

3.  DC9V power adapter

4.  RS232 data cable and communication software (download from www.amtast.com, search “amt620”)