Yoke P911 Benchtop pH Meter

Overview

The Yoke P911 Benchtop pH Meter is a high-precision, single-parameter electrochemical analyzer engineered for routine and quality-critical pH, mV, and temperature measurements in laboratory, QC/QA, and educational environments. Built upon a stable potentiometric measurement principle—utilizing the Nernst equation to quantify hydrogen ion activity—the P911 delivers traceable, reproducible results across an extended pH range of −2.000 to 19.999. Its design adheres to fundamental electrochemical instrumentation standards, featuring ultra-high input impedance (>1 × 10¹² Ω) and sub-picoampere input current (<2 × 10⁻¹² A) to minimize electrode polarization and ensure signal fidelity—even with high-impedance glass electrodes or low-conductivity samples. The instrument supports full GLP (Good Laboratory Practice) workflows through timestamped data logging, automatic calibration diagnostics, and audit-ready parameter recording.

Key Features

• 6.5-inch LED display with high-contrast, multi-parameter readout (pH, mV, temperature, electrode status, calibration progress, and time/date)
• Industrial-grade Omron tactile membrane keypad rated for >100,000 actuations—optimized for glove-compatible operation and long-term reliability
• Auto-buffer recognition across three internationally referenced calibration series: US/EU (e.g., pH 4.01, 7.00, 10.01), NIST-traceable (e.g., pH 4.005, 7.000, 10.012), and Chinese national standard buffers (GB/T 27505–2011)
• Integrated temperature compensation (manual or automatic, 0–100 °C) using either built-in sensor or external Pt1000 probe input
• IP54-rated enclosure—dust-protected and splash-resistant—suitable for shared lab benches and humid environments
• Onboard memory stores up to 2000 measurement records with full metadata (pH value, mV, temperature, calibration ID, date/time, electrode ID if registered)

Sample Compatibility & Compliance

The P911 is validated for aqueous and low-ionic-strength solutions typical in pharmaceutical dissolution testing, environmental water analysis, food & beverage quality control, and academic research. It accommodates standard BNC-input combination pH electrodes (e.g., gel-filled, refillable, or double-junction configurations) and supports electrode health diagnostics—including slope calculation (%), offset voltage (mV), and response time estimation—to assist users in verifying sensor readiness prior to measurement. The device conforms to ISO/IEC 17025-relevant operational rigor and supports regulatory documentation requirements under FDA 21 CFR Part 11 when paired with validated data export procedures (e.g., timestamped CSV via USB mass storage). All calibration and measurement data comply with GLP record-keeping expectations, including mandatory fields for operator ID, sample ID, and environmental conditions.

Software & Data Management

Data are stored internally in non-volatile memory and exported directly via USB 2.0 interface to standard USB flash drives. Exported files use UTF-8 encoded CSV format—natively compatible with Microsoft Excel, LibreOffice Calc, and LIMS import modules—without proprietary software dependencies. Each record includes column headers: “Timestamp”, “pH”, “mV”, “Temperature (°C)”, “Calibration Buffer Used”, “Electrode Slope (%)”, and “Operator ID” (user-definable). Optional Bluetooth 4.2 module enables wireless pairing with certified thermal printers (e.g., Zebra ZQ520, Brother QL-820NWB) and secure BLE data streaming to Windows/macOS applications or mobile platforms (iOS/Android) via Yoke’s documented API framework—facilitating integration into automated reporting pipelines.

Applications

• Pharmaceutical QC: pH verification of injectables, buffers, and stability study samples per USP and EP 2.2.3
• Environmental labs: Monitoring pH in wastewater effluent, surface water, and acid mine drainage per ASTM D1293 and ISO 10523
• Food & beverage: Batch consistency checks for dairy, brewing, and juice processing lines
• Academic teaching: Electrochemistry labs requiring Nernstian behavior demonstration and calibration protocol training
• Research chemistry: High-precision titration endpoint detection and zeta potential sample conditioning

FAQ

Does the P911 support automatic temperature compensation (ATC) with external probes?
Yes—it accepts standard Pt1000 RTD sensors via dedicated analog input, enabling ATC across 0–100 °C with ±0.1 °C resolution.
Can calibration history be reviewed or deleted individually?
Calibration events are logged with timestamps and buffer IDs; users may review full history but cannot selectively delete entries—only clear all logs via administrator password.
Is the USB export function compatible with macOS and Linux systems?
Yes—CSV exports are plain-text and universally readable; no drivers required. Tested on macOS Ventura and Ubuntu 22.04 LTS.
What electrode types are recommended for extreme pH ranges (e.g., 13)?
For pH 13, select high-pH resistant electrodes with Li⁺-glass formulations. Standard electrodes may exhibit alkaline error above pH 12.5.
Does the instrument meet electromagnetic compatibility (EMC) standards for laboratory use?
Yes—complies with IEC 61326-1:2013 Class A emission and immunity requirements for professional laboratory equipment.