Description

The Ametek WDG-V is a high-accuracy digital weight indicator and load cell signal conditioner engineered for industrial process weighing applications, including tank weighing, hopper batching, conveyor belt scales, and loss-in-weight feeders. As part of Ametek’s legacy line of precision instrumentation—originally developed under the Stoddard Industries or Sartorius Industrial Products heritage—the WDG-V converts low-level millivolt signals from strain gauge load cells into stable, calibrated digital readings and standardized analog or serial outputs for integration into PLCs, DCS systems, or standalone control panels.

Designed for reliability in demanding environments, the Ametek WDG-V features a robust metal housing with a NEMA 4X-rated front panel, protecting internal electronics from dust, moisture, and washdown conditions common in food processing, chemical plants, and bulk material handling facilities. Its dual-display architecture shows both gross/net weight and tare values simultaneously, while programmable setpoints enable direct control of fill/empty relays—eliminating the need for external logic modules in simple batching tasks. The WDG-V supports up to four 350-ohm load cells, auto-zero tracking, and digital filtering to suppress vibration-induced noise, ensuring consistent performance even on unstable platforms or outdoor silos.

Widely deployed as a drop-in replacement for obsolete analog gauges (such as the WDG-III or WDG-IV series), the Ametek WDG-V bridges the gap between legacy mechanical scales and modern digital automation. By delivering repeatable, drift-free measurements with configurable outputs, it enhances process consistency, reduces material waste, and supports compliance with quality standards like ISO 9001 or GMP—making the WDG-V far more than a display: it’s a critical node in precision material management.

Technical Specifications

Main Features and Advantages

High-resolution signal conditioning with advanced filtering: The WDG-V employs a 24-bit A/D converter and multi-stage digital filtering to deliver stable weight readings even in high-vibration environments—critical for applications like truck scales near rail lines or silo weighing in cement plants. Its auto-zero tracking compensates for thermal drift or minor mechanical shifts over time, maintaining calibration without frequent manual intervention.

Flexible output options for seamless system integration: Whether your control system requires a 4–20 mA loop for DCS analog input cards or an RS-232 stream for batch recorders, the WDG-V provides both simultaneously. The analog output is fully isolated and scalable (e.g., 4 mA = 0 kg, 20 mA = 10,000 kg), while the serial port supports continuous or polled data transmission in ASCII format—ideal for interfacing with Rockwell PLCs or Wonderware SCADA.

User-friendly operation with minimal setup time: The WDG-V features intuitive front-panel buttons and a clear LED display that guides users through calibration, tare, and setpoint configuration without software. Calibration can be performed using live weights or simulated mV inputs, and all settings are stored in non-volatile memory—surviving power cycles and reducing commissioning delays during maintenance swaps.

Robust industrial construction for long service life: Unlike plastic-bodied competitors, the WDG-V uses a die-cast aluminum front bezel and steel enclosure, resisting impact, corrosion, and EMI. Its conformal-coated PCB ensures reliability in humid or chemically aggressive atmospheres, such as pulp & paper mills or wastewater treatment plants where chlorine exposure is common.

Dual relay control for standalone batching: The WDG-V includes two independent SPDT relays that can trigger fill valves, conveyor stops, or alarm horns based on high/low weight thresholds. This enables simple “fill-to-target” operations without a PLC—reducing system cost for small-scale blenders or additive dosing stations.

Backward compatibility with legacy scale infrastructure: Designed as a direct upgrade for older WDG-series gauges, the WDG-V matches existing cutout dimensions and wiring pinouts—allowing retrofit in minutes without panel modifications. This makes it a cost-effective path to digital accuracy for aging production lines still running on analog instrumentation.

Application Field

The Ametek WDG-V is extensively used across industries where precise weight measurement directly impacts product quality, safety, or regulatory compliance. In food and beverage manufacturing, it controls ingredient batching for sauces, dairy blends, or dry mixes—ensuring recipe fidelity and avoiding costly overfills. Similarly, in pharmaceutical compounding, the WDG-V’s high repeatability supports GMP documentation by providing auditable weight records via its RS-232 port.

In bulk solids handling—such as grain elevators, coal terminals, or plastic pellet silos—the WDG-V monitors inventory levels in real time, triggering reorder alerts or preventing overloading that could damage structural supports. Its vibration immunity proves invaluable on outdoor bins subject to wind sway or nearby equipment operation. Chemical plants rely on the WDG-V for closed-loop control of catalyst hoppers, where ±0.1% dosing accuracy affects reaction yield and emissions.

Even in recycling and waste management, the WDG-V powers compactors and balers by measuring bale weight before ejection, optimizing logistics and billing. Municipal water districts use it in polymer feed systems for flocculation control, where consistent dosing prevents sludge carryover. Across all these scenarios, the WDG-V transforms raw load cell signals into actionable intelligence—proving that in industrial automation, accurate weight isn’t just data—it’s value.

Related Products

• WDG-IV: Predecessor analog weight gauge—lower accuracy, no digital output

• WDG-V-485: Variant with RS-485 Modbus RTU instead of RS-232

• LCI-100: Ametek load cell junction box—pairs with WDG-V for multi-cell systems

• Sartorius PR6201: High-precision load cell—commonly used with WDG-V in tank weighing

• WDG-V-DIN: DIN-rail mount version of WDG-V for control cabinet installation

• AMETEK 9300: Advanced digital indicator—successor with Ethernet/IP and color touchscreen

• WDG-V-RELAY-KIT: External relay expansion module for additional control points

• CAL-WEIGHT-KIT: Certified test weights—recommended for field calibration of WDG-V

Installation and Maintenance

Pre-installation preparation: Before installing the Ametek WDG-V, verify that the load cell wiring follows a 6-wire (sense+/-) configuration if cable runs exceed 50 feet, to compensate for voltage drop. Ensure the excitation voltage at the load cell terminals measures 10 VDC ±0.2 V. Mount the WDG-V in a location free from direct steam, RF sources, or excessive heat (>60°C). For panel mounting, use the provided gasket to maintain NEMA 4X integrity, and ground the chassis to the plant earth grid to prevent ground loops.

Maintenance recommendations: The Ametek WDG-V should undergo annual calibration using certified test weights traceable to NIST standards. Check terminal tightness every six months, especially in high-vibration areas. If the display flickers or readings drift suddenly, inspect the load cell shield wire for continuity to ground—shield faults are a common cause of noise. Keep firmware (if applicable) updated via serial port, though most WDG-V units are hardware-configured. Always power down before connecting/disconnecting load cells to avoid damaging the sensitive input amplifier.