Electric resistance standard AR-1250A/B

This model AR-1250 standard resistor is specifically designed for use as an external standard resistor in AC/DC thermometry bridges and ultra-precise thermometry instruments, and can also be utilized for resistance value transfer in electrical measurements. It employs a highly stable, oil-encapsulated metal foil resistor element. The unit is supplied only after undergoing temperature compensation, resistance value matching, and prolonged screening and aging processes. The product features an all-metal enclosure with a fully oil-filled internal cavity. This effectively isolates it from air, mitigates the impact of ambient temperature, and enhances its long-term (annual) resistance stability. The Type A model can achieve a stability better than 2 ppm per year, and does not require placement in a constant temperature oven or oil bath. - Nominal Value: 1Ω, 10Ω, 25Ω, 100Ω, 1KΩ, 10KΩ, 100KΩ, 1MΩ - Operating Temperature: 18°C ~ 28°C - Storage Temperature: 0°C ~ 45°C - Calibration Temperature: 23°C±0.5°C - Annual Stability: 1Ω, 10Ω:±3ppm(A)/±6ppm(B) - Temperature Coefficient: ±0.5ppm/°C - Max. Power Consumption: 1W - Dimensions: 130mm (5.1") x 105mm (4.1") x 82mm (3.2") - Net Weight: Approximately 1 kg (2.2 lb) Performance Table: - Nominal Value: 1Ω, 10Ω, 25Ω, 100Ω, 1KΩ, 10KΩ, 100KΩ, 1MΩ - Annual Stability A: ±3ppm - Annual Stability B: ±6ppm - Factory Calibration (23°C): ±5ppm - Max. Current: 500mA, 100mA, 50mA, 20mA, 10mA, 3mA, 1mA, 0.1mA - Highly stable, oil-encapsulated metal foil resistor element - All-metal enclosure with fully oil-filled internal cavity - Temperature compensation and resistance value matching - Long-term (annual) resistance stability - Does not require constant temperature oven or oil bath (Type A) Technical Specifications: - Nominal Values: 1Ω, 10Ω, 25Ω, 100Ω, 1KΩ, 10KΩ, 100KΩ, 1MΩ - Operating Temperature: 18°C ~ 28°C - Storage Temperature: 0°C ~ 45°C - Calibration Temperature: 23°C±0.5°C - Annual Stability: 1Ω, 10Ω:±3ppm(A)/±6ppm(B) - Temperature Coefficient: ±0.5ppm/°C - Max. Power Consumption: 1W - Dimensions: 130mm x 105mm x 82mm - Net Weight: Approximately 1 kg