GenRad 1482 Series Induction Standard

The 1482 Series from IET Labs, continuing the GenRad tradition, is recognized worldwide as one of the most reliable and stable low-frequency inductance standards available. Designed for laboratories and national metrology institutes that require a highly accurate reference, these primary standard inductors offer exceptional long-term stability, typically better than 10 ppm per year, and remain within ±0.01% annually. Their proven track record over decades makes them ideal for calibration, metrology, and demanding research environments.

High Stability and Exceptional Accuracy

Each inductor in the 1482 Series is built to deliver outstanding long-term stability. The inductors feature a ceramic, non-magnetic core and a uniformly wound toroidal coil that minimizes external magnetic interference. Because of this construction, magnetic pickup from surrounding fields is virtually eliminated. The coil is suspended in a mixture of cork and silica gel and then encapsulated in a robust aluminum case, providing mechanical damping and thermal stability.

With a temperature coefficient of approximately 30 ppm per degree Celsius, the inductors exhibit predictable behavior that allows for simple, accurate temperature corrections. Each unit is individually calibrated at multiple frequencies and supplied with a detailed calibration certificate that lists measured values, test conditions, and measurement uncertainties.

Construction and Ease of Use

The 1482 Series covers a wide inductance range from 1 µH to 10 H. Models of 500 µH and above include three terminals, enabling both two-terminal and three-terminal connections. Lower-value inductors are equipped with additional terminals that allow short-circuit compensation without altering the setup. This ensures that the measured inductance remains independent of lead inductance, which is particularly important for very low inductance values.

All models feature high-quality, gold-plated binding posts spaced at the standard ¾ inch. These low-resistance terminals provide excellent contact reliability and include a removable grounding strap for flexible measurement configurations.

Low-Frequency Performance

The 1482 inductors are designed as low-frequency reference standards and are calibrated at 100 Hz, 200 Hz, 400 Hz, and 1 kHz. Units below 2 mH are also calibrated at 10 kHz. Their construction results in high Q-factors at 100 Hz, with each unit’s actual Q-value documented in its calibration certificate. Resonant frequency and DC resistance are also measured and listed individually.

For higher-power applications, the inductors offer generous headroom: they can dissipate up to 3 watts for a 20 °C temperature rise, while precision measurements are typically performed at 200 mW to maintain optimal stability.

A Reliable Standard for Advanced Measurement Environments

The 1482 Series has been used by national laboratories and precision metrology facilities around the world for decades. Their combination of mechanical robustness, thermal stability, and traceable calibration makes them a trusted reference for verifying, comparing, and calibrating instruments such as bridges and LCR meters.

Whether used in research facilities, manufacturing quality control, or primary metrology laboratories, the 1482 Series offers a stable, reproducible, and traceable inductance reference for any application demanding the highest level of precision.

MODELS

For more information please contact our consultants.