Bently Nevada TK81 Tunable Filter/Vibration Meter

Overview

The Bently Nevada TK81 Tunable Filter/Vibration Meter is a portable handheld instrument for basic vibration measurements. It can display vibration in both unfiltered (overall) and filtered modes, accepting inputs from displacement, velocity, and acceleration transducers, though it does not provide power for them. Its filtering capability is especially useful for diagnosing vibration problems at specific frequencies across various machinery.

Specifications

Inputs

• Signal: Accepts displacement, velocity, or acceleration.
• Maximum Input: 10 V peak-to-peak.
• Scale Factor: Selectable from 5 to 9999 mV per engineering unit.
• Input Impedance: 95 kΩ.

Signal Conditioning

• Frequency Response: 1.66 Hz to 1,666 Hz (100 to 100,000 RPM).
• Integration: Single integration available for frequencies above 10 Hz (600 RPM).
• Filter:
  • Operating Range: 1.66 Hz to 1,666 Hz (100 RPM to 100,000 RPM).
  • Type: Digital, approximates an analog filter with a Q of 11.

Outputs

• Display: 4 line by 16 character LCD.
• Display Units: Selectable Metric or English, peak-to-peak, zero-to-peak, or rms.
  • Note: RMS readings may fluctuate @ < 10 Hz (600 RPM).
• Accuracy:
  • Within 5% for non-filtered, non-integrated signals across full frequency range.
  • Within 10% for all RMS measurements and filtered signals.

Power Requirements

• Battery: 9-Volt alkaline transistor battery (NEDA 1604A).
• Battery Life: 20 hours nominal.

Environmental Limits

• Operating Temperature: +0°C to +40°C (+32°F to +104°F).
• Storage Temperature: -20°C to +70°C (-4°F to +158°F).
  • Note: Battery stored above +104°C (+219°F) or below 0°C (+32°F) will have a reduced shelf life.
• Relative Humidity: Up to 90% non-condensing.

Physical

• Size:
  • Height: 191 mm (7.5 in)
  • Width: 102 mm (4.0 in)
  • Depth: 58 mm (2.3 in)
• Weight: 316 g (0.7 lb)