Resistance calibrator 742A series

ohmmeterfor electrical measuring instrumentsfor acoustic emission detectors

Product overview

• High-accuracy working standards for precision, on-site resistance calibration.
• Compact, rugged calibrators designed for easy transport and field use.
• No oil or air baths required; operating temperature range 18°C to 28°C with temperature characterization provided.
• Six-month stability typically 2.5 ppm; supplied with temperature correction table in 0.5°C increments.
• Designed to minimize resistance changes from thermal and mechanical shock; retrace typically < 2 ppm after 0°C–40°C cycling.

Key features

• High-accuracy working standards suitable for on-site calibration of resistance measurements.
• Small, rugged, and easy to transport for field laboratories and service engineers.
• Temperature stability and six-month stability to 2.5 ppm.
• Operating temperature: 18°C–28°C; temperature characterization included to reduce uncertainty.
• Resistance change minimization for thermal and mechanical shock.

Specifications (table)
General Specifications
12 values from 1 Ω to 19 MΩ in x1 and x1.9 ranges — Best 1 year specification: ±4 ppm
Operating Temperature — 18°C to 28°C
Storage Temperature — 0°C to 40°C
Retrace error (hysteresis): 23°C–18°C–23°C cycle — negligible resistance shift
23°C–28°C–23°C cycle — negligible resistance shift
23°C–0°C–23°C cycle — < 2 ppm resistance shift
23°C–40°C–23°C cycle — < 2 ppm resistance shift
Calibration documentation — 17025-accredited calibration report included
Size — 8.6 cm H x 10.5 cm W x 12.7 cm D (3.4 in H x 4.15 in W x 5 in D)
Weight — 0.68 kg to 0.91 kg depending on model


Models

• 742A-1 — 1 Ω Resistance Standard
• 742A-1.9 — 1.9 Ω Resistance Standard
• 742A-10 — 10 Ω Resistance Standard
• 742A-25 — 25 Ω Resistance Standard
• 742A-100 — 100 Ω Resistance Standard
• 742A-1k — 1 kΩ Resistance Standard
• 742A-10k — 10 kΩ Resistance Standard
• 742A-19k — 19 kΩ Resistance Standard
• 742A-100k — 100 kΩ Resistance Standard
• 742A-1M — 1 MΩ Resistance Standard
• 742A-10M — 10 MΩ Resistance Standard
• 742A-19M — 19 MΩ Resistance Standard

Technical specifications

• Available values: 12 values from 1 Ω to 19 MΩ in x1 and x1.9 ranges.
• Best 1-year specification: ±4 ppm.
• Six-month stability: 2.5 ppm.
• Operating temperature: 18°C to 28°C (use supplied calibration table for 0.5°C correction increments to reduce uncertainty).
• Storage temperature: 0°C to 40°C.
• Retrace (hysteresis): typically negligible for small cycles; < 2 ppm for 0°C–40°C cycling.
• Calibration documentation: 17025-accredited calibration report supplied with each unit.
• Size: 8.6 cm H x 10.5 cm W x 12.7 cm D.
• Weight: approximately 0.68–0.91 kg depending on model.
• No oil or air baths required; suitable for on-site use with temperature characterization provided.