EUROPE


Vibration Pickup

Servo Type Accelerometer

A motion is sensed by a displacement detector, a current is fed to the coil to get back the pendulum mass to the original position. This current will be proportional to the acceleration, that is converted to an output voltage. The servo type accelerometer is for the earthquake monitoring or measurements of micro tremor on the civil engineering structures because of its higher sensitivity and stability or more accurate phase responses in the lower frequency range than those of other vibration transducers.

Features

■ Detectable down from DC
■ Advanced linearity and high resolution
■ High sensitivity and large output voltage
■ Excellent phase response in low frequency range
■ Stable operation because of armature flexure suspension free from friction or fatigue
■ Static sensitivity calibration is possible using the gravity acceleration
■ Long cable can be used because of the pretty low output impedance

[ Frequency response ]

Though the upper frequency limit of the servo accelerometer should be defined by the natural frequency of the pendurum that is affected by displacement negative feedback, it is actually limited by the installed low pass filter. Lower frequency components can be detected down to DC acceleration. However, lower limit will depend on the integral characteristic of the amplifier in case of convension to velocity or displacement.

[ Phase response ]

Phase response of the servo accelerometer is favorable down from low frequency area (almost DC)

Product lineup

Drip
proof
VP-5113 HHV - Fixed on the ground -

■ Specifications

Sensitivity direction HHV
Maximum measurable
acceleration
29.4 m/s2
Sensitivity 0.204 V (m/s2) ± 5 % or less
Frequency range DC to 100 Hz
Natural frequency > 400 Hz
Linearity ± 0.1 % full scale
Resolution 4.9 x10-5 m/s2 or less
Power supply DC ± 11 to 16 V
Operating temperature
range
-25 to +70 ゚C
Structure Dust proof, drop proof (equivalemt to IP65)
Cable connection Drip proof packing
Material Aluminum die cast
Weight 5 kg
Self test Equipped

Water proof General type VP-9462 HHV - Fixed on the ground -

■ Specifications

Sensitivity direction HHV
Maximum measurable acceleration 29.4 m/s2
Sensitivity 0.204 V (m/s2) ± 5 % or less
Frequency range DC to 100 Hz
Natural frequency > 400 Hz
Linearity ± 0.1 % full scale
Resolution 4.9 x10-5 m/s2 or less
Power supply DC ± 11 to 16 V
Operating temperature range -25 to +70 ゚C
Structure Water-proof
Cable connection Water-proof packing
Material Brass tube C2700T
Weight 5.5 kg
Self test Equipped

Water proof General type VP-9562 HHV - Bore hole type -

■ Specifications

Sensitivity direction HHV
Maximum measurable acceleration 29.4 m/s2
Sensitivity 0.204 V (m/s2) ± 5 % or less
Frequency range DC to 100 Hz
Natural frequency > 400 Hz
Linearity ± 0.1 % full scale
Resolution 4.9 x10-5 m/s2 or less
Power supply DC ± 11 to 16 V
Operating temperature range -25 to +70 ゚C
Structure Water-proof
Cable connection Water-proof packing
Material Brass tube C2700T
Weight 6.5 kg
Self test Equipped