Acceleration Sensors

At WSI, we have quite a wide range of Acceleration sensors under “BEST” brand name.

– Strain Gauge type Sensor

– Piezo resistive type Sensor

– Piezo capacitive type Sensor

– Piezo Electric Type Sensor

Acceleration Sensors

Our range of Acceleration Sensors starts from general purpose to most sophisticated high end Acceleration sensors for testing development purposes.

Common types of accelerometer sensors

Category                                       Key Technology

Capacitive                                    Metal Beam or Micro machined feature produces capacitance; change in capacitance related to acceleration.

Piezoelectric                               Piezoelectric Crystal mounted to mass – Voltage output converted to           acceleration.

Piezo-Resistive                           Beam or Micro machined feature whose resistance changes with                 acceleration.

Hall Effect                                   Motion converted to electrical signal by sensing of changing magnetic       fields.

Magnetoresistive                       Material resistivity changes in presence of magnetic fields.

Heat Transfer                            Location of heated mass tracked during acceleration by sensing     temperature.

Important Handling / Installation Requirements for Acceleration Sensor

-Rigid Mounting

  • Beeswax
  • Double sided tape
  • Bolt(s)

-No loose Wires

  • Loose wires can create false signals.
  • Secure wires firmly to mounting body.

– Weight of Sensor

  • Should be approximately an order of magnitude less than the object being measures.

– Don’t drop the Sensor.

  • Extreme jerring accelerations can cause permanent errors in device output.

Effect of Tilt

  • DC response sensors measures tilt. Mounting errors are therefore significant.
  • At 1 degree tilt in the 0g position creates an output error equivalent to a 10 degree tilt in the +1g or -1g positions.
  • 0 g is most sensitive to mounting errors.

Strain Gauge Accelerometers

(BAS-011)

Strain Gauge Accelerometer

The BAS-011 is a general purpose accelerometer that is especially useful for measuring very low frequencies. Compared with oil damped accelerometers, the air damped BAS-011 is less sensitive to temperature variations, thus providing more accurate measurements.

The sensing element is fitted with a fully temperature compensated wheatstone bridge comprised of high stability, micro-machined silicon strain gauges.Packed in a rugged aluminum alloy case, the BAS-011 accelerometers are easy to mount.

  • Full scale range +/- 2 g to +/- 500g
  • DC response
  • Solid state reliability
  • High over range capability
  • integrated over range stops
  • Built-in critical air Damping (~0.7)
  • Lightweight aluminum alloy construction
  • Operating temperature range from -20 to +80 degree celsius
  • High level 2mv/V output.
  • Impedance: 350 Ohms, 4 wire circuit.

Technical Specifications

Linearity: +/-2% FS

Transverse Sensitivity: >/= 3% FS Standard (+/-1% Optional)

Compensated temperature range: 0 to 60 degree celsius

Zero shift in OTR: </= 2% FS/60 degree celsius

Sensitivity shift in OTR: </=2% of Reading / 60 degree Celsius

Weight: </= 25 grams

Construction material: Aluminium


Piezoresistive Accelerometer

(BAS-022)

Piezo resistive Accelerometer

WSI’s BAS-022 is Piezoresistive Accelerometer consists of a piezoresistive MEMS sensor, a semiconductor temperature sensor and all of the necessary front end signal conditioning which includes data acquisition, data processing and the intelli bus compliant digital bus. It is packed in a small, low profile metal case with two pigtail connectors which are used for chaining the intellibus based network. Its low noise front end signal conditioning and programmable gain allows for measurement of a wide range of vibration levels. Temperature readings from its built in sensor may be used for on or off board temperature corrections.

There are two software selectable 3-pole anti aliasing filters. One with a cut off frequency at 2KHz and other at 360Hz. The 16bit ADC samples data at a programmable rate up to 250 ksps. A powerful processor performs digital signal processing algorithms.

Features:

  • Digital output
  • Programmable full scale +/- 12.5g to +/- 1000 g
  • Noise Floor: 12 mg rms
  • Frequency Response: Dc to 5 KHz
  • Programmable Digital Filter
  • Filter Corners; 10Hz to 12 KHz
  • 16 bit ADC with sample rate upto 250ksps

Specifications:

Dynamic Characteristics                                Units

Full scale input range                                     g pk                          +/- 12.5 to +/- 1000 g programmable

Accuracy                                                            %                              +/- 0.2 Electronic Signal Conditioner

+/- 1.5 Sensor Calibration Uncertainty at 100 Hz

Noise                                                                  %                               0.2 of Full scale max

Thermal Sensitivity Shift                              %/Degree F              0.002

Transverse Sensitivity                                   %                                 <5 Typical

Amplitude Linearity                                      %                                  <2

Bandwidth (F-5%)                                         Hz                                1 to 5000 no filter

Anti aliasing LPF                                           Hz                                 3 Pole Butterworth


 

Piezoelectric Accelerometer General Purpose

BAS-033

Piezo Electric Accelerometer

Our model no BAS-033 is a general purpose Piezoelectric Accelerometer. The unit features a top connector mounting convenience in limited space. The accelerometer is a self generating device that required no external power source for operation.

BAS-033 have Crystal/Quartz/ Ceramic Element operating in annular shear mode. This sensor exhibits low base strain sensitivity, high resonance frequency and excellent output stability over time.

Signal ground is connected to the outer case of the unit and when used with an isolated mounting stud, the accelerometer case is electrically isolated from ground. A low noise coaxial cable is supplied for error-free operation.

Specifications:

Dynamic Characteristics                    Units                                 Value

Charge Sensitivity

Typical                                                             pC/g                                     12.0

Minimum                                                        pC/g                                      8.5

Resonance Frequency                                  KHz                                       10 to 200KHz

Amplitude Response(A) +/-5%                  Hz                                         1 to 10000

Transverse sensitivity                                   %                                           </= 3 (</=1 on special order)

Amplitude Linearity (B)                               %                                           1

Resistance Grounding                                  Giga Ohms                          >/= 10

Temperature Range                                                                                    -55 to +177 Degree Celsius

Sealing                                                                                                           Hermetically Sealed

Sinusoidal Vibration limit                           g pk                                      1000

Shock Limit                                                    g pk                                      2000

Base Strain Sensitivity                                 Equiv g pk/strain              0.002

Thermal Transient Sensitivity                   Equiv g pk/Degree Celsius   0.002

Electromagnetic Sensitivity                       Equiv g rms/Gauss            0.0001

Case Material                                                                                               Stainless Steel/ Titanium

Connector                                                                                                     coaxial, 10-32 threads

Mounting Torque                                         Nm                                        2

Leave a Reply