Wavetek 4920

The Wavetek 4920 is an Alternating Voltage Measurement Standard (AVMS) engineered for precision AC voltage calibration in standards laboratories. It delivers high-accuracy RMS measurements across extended voltage ranges with selectable resolution up to 7½ digits, replacing thermal transfer standards with faster setup and improved operational efficiency. The instrument performs AC/DC and AC/AC transfer measurements with exceptional linearity and low noise uncertainty.

– Technical Specifications

Measurement Capability
• AC voltage ranges: 300 mV to 1000 V (standard 3, 10, 30 sequence)
• Optional millivolt ranges: 3 mV to 100 mV or 0.9 mV to 110 mV
• Extended variants: 1 mV to 1200 V
• Display resolution: 5 to 7 digits selectable; 100 nV maximum; 7½ digits available
• Input impedance: > 200 Ω/V or 10 MΩ // 20 pF

Frequency and Accuracy
• High accuracy mode: 1 Hz to 1 MHz (±30 ppm, 1 year @ 23°C ±5°C)
• Standalone measurement: ±28 ppm (1 year @ ±5°C)
• AC/DC transfer: ±14 ppm (1 year @ ±5°C)
• Optional wideband module extends capability to 50 MHz
• VSWR: 1.02:1 from 10 Hz to 50 MHz
• Linearity: 0.2 ppm of full scale
• Noise uncertainty: Better than 0.5 ppm RMS
• Measurement period: 2.5 seconds (including settling time)

Physical and Electrical
• Dimensions: 19″ W × 3.5″ H × 15″ D
• Weight: 15 lbs (6.8 kg)
• Line supply: 100–130 V or 200–260 V, 47–63 Hz
• Power consumption: 37 VA
• Operating temperature: 0°C to +50°C
• Storage temperature: −40°C to +70°C

– Key Features

• Simultaneous voltage and frequency display
• Fully programmable via IEEE-488.2 (GPIB) remote interface
• RS-232 connectivity available
• Calibration traceable to national standards
• Designed to UL1244 and IEC 348 safety standards

– Typical Applications

• AC voltage calibration and transfer standards
• Thermal voltmeter replacement in metrology labs
• Precision AC measurement verification
• AC/DC transfer standardization

– Compatibility & Integration

The 4920 integrates into automated calibration systems via GPIB/IEEE-488.2 programming. Optional millivolt and wideband modules extend measurement scope for specialized requirements.