Himmelstein Mechanical Power Instruments, available from Hylec Controls , are advanced instruments that provide engineering unit display of a strain gage (mV/V) input and a frequency input. They also compute power and perform 21 functions including limit checks, tare, hold, and maximum/minimum capture. Users need not write code or add hardware to be up-and-running a productive test.
The two line alphanumeric readout displays measured and computed data, units of measure and test status. Transducer calibrations are fully automatic, requiring no manual adjustments.
- The following are general specifications of the model 721 Mechanical Power Instrument:
Strain gage input: Any 80Ω to 2kΩ transducer directly wired or transformer coupled. 4, 6, or 7 wire circuits are accommodated.
- Transducer excitation: 3Vrms, 3030Hz ±0.01% sine wave; regulated and short circuit protected.
- Sensitivity: 0.5 to 5mV/V with 50% overrange; automatically scaled.
- Input impedance: 100MΩ in parallel with 33pF.
- Automatic null range: In-phase signals: ±10% of full scale (with 50% overrange), 60% of Full scale (with 0% overrange); Quadrature signals: ±1mV/V.
- Automatic null: In phase: ±10% of F.S. (with 50% overrange), ±60% of F.S. (with 0% overrange); Quadrature: ±1mV/V.
- Auto calibration: Dual polarity shunt calibration with provision for CAL resistor feedback.
- Spurious signal rejection: 60Hz: 120dB common mode, 100dB normal mode; Carrier quadrature: 60dB.
- Antialias filter: 200Hz, 7 pole Bessel response filter.
- Low pass filtering: 4 pole Bessel response digital filter with 11 cutoff frequencies from 0.1 to 200Hz in 1-2-5 steps.
- Signal-to-Noise Ratio1: with 1/10/100/200Hz filters 86/76/66/62dB at 1mV/V F.S. and 86/80/72/66dB at 5mV/V F.S.
- Resolution: 0.01% of F.S.
- Overall accuracy (at 77°F/25°C): 0.02% of F.S., worst case.