A&D AD-4961 Multi-Stage Weight Checkweigher System

Overview

The A&D AD-4961 is a modular, high-speed industrial checkweigher engineered for precision weight verification and dynamic product sorting in regulated manufacturing environments—including food, pharmaceutical, nutraceutical, and consumer goods production lines. Unlike monolithic weigh systems, the AD-4961 adopts a four-unit architecture: feed conveyor module, weighing conveyor module, control unit, and structural frame—each mechanically and electrically decoupled to support rapid field replacement without system recalibration. Its measurement principle relies on high-stability strain-gauge load cells integrated into a rigid stainless-steel weighing platform, operating under controlled dynamic conditions to minimize vibration-induced noise and ensure repeatability at line speeds up to 320 parts per minute. The system complies with fundamental metrological requirements outlined in OIML R51 (automatic catchweighers) and supports traceable calibration protocols aligned with ISO/IEC 17025-accredited practices.

Key Features

• Modular design enabling hot-swap replacement of non-functional units—reducing mean time to repair (MTTR) to under 15 minutes without requiring OEM technician intervention.
• Direct-drive gear transmission system for conveyor belts—eliminating belt slippage and ensuring consistent linear velocity across the full operational range (15–20 m/min).
• Fully stainless-steel frame and control enclosure (SUS304), combined with anodized aluminum conveyor components and food-grade polyurethane belt surface—meeting hygiene standards for wet-clean environments (e.g., IP65-rated ingress protection).
• 7-inch WVGA color touchscreen interface with intuitive icon-based navigation—supporting multilingual UI (English, Japanese, Chinese, Spanish) and real-time graphical feedback including weight distribution histograms and pass/fail trend charts.
• Integrated dual-range weighing capability: 0.01 g resolution at 500 g capacity and 0.1 g resolution at 2000 g capacity—optimized for heterogeneous product portfolios within a single production shift.
• Onboard recipe memory stores up to 1000 distinct product configurations across 10 user-defined groups—enabling rapid changeover between SKUs without external PC dependency.

Sample Compatibility & Compliance

The AD-4961 accommodates solid, rigid, or semi-rigid items measuring 30–300 mm in length and up to 200 mm in width—suitable for packaged tablets, blister cards, canned beverages, snack pouches, and small electronics assemblies. Its mechanical stability and low-noise signal conditioning allow reliable operation even with irregularly shaped or lightly vibrating products. The system meets CE marking requirements under the Measuring Instruments Directive (MID 2014/32/EU) for automatic weighing instruments. It supports audit-ready data integrity through optional timestamped event logging and configurable digital I/O triggers compliant with FDA 21 CFR Part 11 when paired with validated software platforms. Routine verification procedures align with ASTM E177 (Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods) and USP (Weighing on an Analytical Balance).

Software & Data Management

Data acquisition and remote supervision are enabled via native Modbus TCP/RTU protocol implementation—allowing seamless integration with SCADA, MES, and PLC systems (e.g., Siemens S7, Rockwell ControlLogix, Mitsubishi MELSEC). All weight records, pass/fail decisions, and alarm events are timestamped and exportable via USB mass storage or Ethernet transfer in CSV or XML format. The embedded communication stack supports simultaneous connections from up to three external clients—including HMI terminals, supervisory PCs, and metal detectors (via RS-232C handshake). Firmware updates are performed over-the-air using signed binary packages, preserving configuration integrity during version upgrades. Optional cloud gateway modules enable TLS-encrypted telemetry to AWS IoT Core or Azure IoT Hub for centralized fleet monitoring.

Applications

• Pharmaceutical secondary packaging lines verifying tablet count accuracy prior to carton sealing.
• Ready-to-eat meal producers validating net weight compliance per EU Regulation No. 1169/2011 labeling requirements.
• Confectionery manufacturers performing inline rejection of underfilled candy bags based on statistical process control (SPC) limits.
• Medical device assemblers confirming presence and quantity of sterile components in peel-open pouches.
• Contract manufacturers supporting multi-client production schedules with fast recipe recall and secure user-level access control (three-tier permission model).

FAQ

What is the maximum allowable item weight for high-resolution mode?
The AD-4961 achieves 0.01 g resolution only within the 500 g capacity range. Exceeding this limit automatically switches to the 2000 g range with 0.1 g resolution.
Can the system interface with a metal detector without additional hardware?
Yes—the RS-232C port is preconfigured for direct serial handshake with industry-standard metal detection units (e.g., Mettler Toledo Safeline, Thermo Fisher Sentinels), enabling synchronized reject actuation.
Is calibration traceable to national standards?
Calibration certificates issued by A&D’s ISO/IEC 17025-accredited calibration laboratory include NIST-traceable reference masses and uncertainty budgets per ISO/IEC 17025:2017 Clause 6.5.
Does the touchscreen support glove operation?
The projected capacitive display is rated for operation with standard nitrile or latex gloves, and haptic feedback can be enabled for tactile confirmation of touch inputs.
How is firmware updated in a GMP environment?
Firmware updates require digital signature verification and generate immutable audit logs—including operator ID, timestamp, pre-update checksum, and post-installation functional test results—fully compatible with ALCOA+ data integrity principles.