Hioki 8947 CHARGE UNIT

Acceleration pickup and voltage input amplifier The CHARGE UNIT 8947 is equipped with circuits for two independently usable input channels. As with previous analog units, simply slot the 8947 into the MEMORY HiCORDER for use.

• In addition to its charge input terminals, the 8947 is equipped with BNC terminals that support internal pre-amplifier pickup sensors
• Not only ordinary piezoelectric acceleration pickups, but voltage output acceleration pickups with internal pre-amplifiers can be connected directly to the 8947, which supplies a constant current power supply for pre-amplifier operation.
• Accommodates voltage signal inputs
• In addition to acceleration pickup signals, the 8947 can also measure ordinary voltage signals.
• Internal anti-aliasing filter
• The 8947 is equipped with an anti-aliasing filter that is indispensable when performing FFT analysis on vibration waveforms.
• The 8947 can be used for the following applications: Measuring engine vibration, Measuring brake vibration, Measuring pump vibration, Measuring bearing vibration, Measuring vibration of vibrators in cellular telephones, CD player vibration testing ... and other types of vibration endurance testing

Basic Specifications

• Input Number of channels: 2, Measurement objects can be selected individually for each channel. Full isolation between inputs, and between inputs and recorder. Common GND for voltage input and charge input channels. Voltage and pre-amplifier internal inputs: BNC terminals Charge input: miniature connector (#10-32 UNF) Suitable converters Charge input: piezoelectric charge output acceleration pickup sensors Internal pre-amplifier input: acceleration pickup sensors with built-in pre-amplifier
• Measurement ranges
• Charge input (miniature connector)
• Pre-amplifier internal input (BNC terminal) 50 m (m/s 2)/DIV to 10 k (m/s 2)/DIV, 12 ranges x 6 types, Measurement resolution is 1/80 to 1/32 of range (change according to measurement sensitivity), Measurement sensitivity: 0.1 pC to 10 pC/ (m/s 2), Pre-amplifier internal input measurement sensitivity: 0.1 mV to 10 mV/ (m/s 2) * When attached to recorder where full-scale (f.s.) = 20 divisions
• 100 m (m/s 2)/DIV to 20 k (m/s 2)/DIV, 12 ranges x 6 types, 1/160 to 1/64 of range, Measurement sensitivity: 0.1 pC to 10 pC/ (m/s 2), Pre-amplifier internal input measurement sensitivity: 0.1 mV to 10 mV/ (m/s 2) * When attached to recorder where full-scale (f.s.) = 10 divisions
• Amplitude accuracy: ±2 % f.s. Frequency characteristics: 1 to 50 kHz +1/-3 dB Low-pass filter: 500/5 kHz Pre-amplifier driving power supply: 2 mA ±20%, +15 V ±5% Highest input charge : ±500 pC (high sensitivity side 6 ranges), ±50000 pC (low sensitivity side 6 ranges)
• Measurement ranges Voltage input (BNC terminal) 500 µV to 2 V/division, 12 ranges, Measurement resolution is 1/80 to 1/32 of range (change according to measurement sensitivity) * When attached to recorder where full-scale (f.s.) = 20 divisions 1 mV to 5 V/division, 12 ranges, 1/160 to 1/64 of range * When attached to recorder where full-scale (f.s.) = 10 divisions
• DC amplitude accuracy: ±0.4 % f.s. Frequency characteristics: DC to 400 kHz +1/-3 dB
• Low-pass filter: 5/500/5 k/100 kHz Input coupling: DC, AC, GND
• Max. allowable input: 30 V rms or 60 V DC
• Common functions to all measurement ranges Anti-aliasing filter: can be turned ON or OFF, cut off frequency is the time axis, connected and set automatically by the frequency axis range
• Maximum sampling rate 1 MS/s (simultaneous sampling of two channels)
• Max. rated voltage to earth 30 V rms or 60 V DC (upper voltage which when applied to input channel casing or between input channels does not damage them)
• Accessories None * The input cord is optional