The Vishay Measurements 1550A Strain Indicator Calibrator is a precision instrument for calibration and verification of strain gauges and measurement systems. It generates accurate, stable resistance values using true Wheatstone bridge circuitry to simulate strain gauge behavior across quarter, half, and full bridge configurations. With 66 ultra-stable precision resistors, the 1550A delivers repeatability and accuracy traceable to NIST standards, making it essential for laboratory and field quality control in strain measurement applications.
Technical Specifications
Bridge Configuration & Resistance
• Quarter, half, and full bridge configurations
• Supports 120Ω and 350Ω bridge resistances
• Internal bridge completion: 120Ω, 350Ω, and 1000Ω quarter bridges; 60Ω to 2000Ω for half or full bridge
Strain & Output Range
• Strain range (direct reading): ±99,900 με in 100 με increments
• Transducer range: ±49.95 mV/V in 0.05 mV/V increments
• Two active arms: 0 to ±99,900 με @ GF = 2.00
• One active arm: 0 to ±49,950 με @ GF = 2.00
• Full-bridge output at 000: 50 με maximum (0.025 mV/V)
Accuracy & Repeatability
• Accuracy: ±0.025% of setting ±1 µε (0.0005 mV/V), maximum; ±0.01% of full scale
• Repeatability: ±1 µε (0.0005 mV/V), maximum
• NIST-traceable calibration
Input/Output Characteristics
• Input resistance: ±0.05% maximum from nominal
• Output resistance: ±0.05% from nominal at 000 µε; –0.25% at ±99,900 µε
Excitation Voltage
• 120Ω: up to 10 VDC (max 25 V AC/DC)
• 350Ω: up to 15 VDC (max 25 V AC/DC)
Power & Physical
• Input: 100-240 V AC, 50/60 Hz
• Dimensions: 19 × 8 × 3.5 inches (rack-mountable); case 5-3/4 H × 8-1/4 W × 7-3/4 D inches
• Weight: Approximately 5 lbs (2.3 kg)
– Key Features
• True Wheatstone bridge with precision resistor network
• Positive and negative strain simulation capability
• Multiple active arm configurations for flexible testing
• High-resolution output in both microstrain and mV/V units
– Typical Applications
• Strain gauge calibration and verification
• Strain indicator system validation
• Field and laboratory measurement system quality assurance
• Transducer output simulation and testing
– Compatibility & Integration
The 1550A interfaces with standard strain measurement instruments via direct bridge connection, supporting industry-standard 120Ω and 350Ω gauge resistances across all common bridge topologies.
