RL-C21

Vibration control system

RL-C21
RL-C21
RL-C21
RL-C21
State-of-the-art vibration control system for electro-dynamic shakers. The system is distinguished by simplicity, reliability and high safety standard. The controller has a modular scalable architecture, which allows the user to get from 1 to 32 input channels.

The configuration of RL-C21 system is flexible: it is determined by the user and can be modified at any time.

The most innovative techniques of digital signal processing are embedded in the system. All calculations and safety checks are run by a DSP directly in the controller. This feature provides the highest level of shaker protection.

The system enables running multishaker tests and successfully controls two- and three-axes shakers, as well as vibration shakers with up to 6 degrees of freedom.

The presence of a galvanic isolation in the input chains allows effectively protecting input chains from breaks.

RL-C21 is used with a specialized vibration test software package VisProbe SL.

Software

VisProbe SL

VisProbe SL

VisProbe SL v36 (x64)
See all versions

Specifications

Input

  • Analog channels
    1÷32
  • Sensor type
    IEPE, TEDS, charge, displacement, velocity, force sensors
  • Filtration
    Analog, digital high-pass and low-pass filters
  • Voltage range
    ±10 V
  • Dynamic range
    ≥ 120 dB
  • Noise level
    < 20 mV
  • Channels crosstalk
    ≤ -100 dB

Output

  • Frequency range
    0.1÷35000 Hz
  • Analog channels
    1 ÷ 8 control channels, Up to 8 COLA channels
  • DAC resolution
    24 bits
  • Frequency range
    0.1÷35000 Hz
  • Relative frequency error
    ≤ 5×(10)-5
  • Filtration
    Analog filters, digital high-pass and low-pass filters
  • Dynamic range
    120 dB

Other

  • Temperature range
    +5 ÷ +50 °C
  • Dimensions
    390×274×54 mm
  • Weight
    2.3 kg
  • Power supply
    110÷245 V

Electromagnetic Compatibility Directive 2014/30/EU

Low Voltage Directive 2014/35/EU

Program interface

Frequently Asked Questions (FAQ)

VisProbe SL does not see the device. There is a message saying that the device has not been found.

Are the settings of channels and shakers, which I specify, saved?

See more FAQ

Product information

RL-C21 and RL-C25. Sine test profile.

RL-C21 and RL-C25. Random test profile.

RL-C21 and RL-C25. Shock test profile.

Education

How to mount accelerometers

Multishaker tests in RL-C21 and RL-C25. Theory and application.

Multishaker tests have recently gained popularity for tests of large objects, which cannot be placed on one shaker, or for simultaneous vibration impact on the object on several axes.

This approach allows imitating the actual vibration conditions of operation more closely.

When using several shakers as one for testing a large object, it is very important to maintain a small phase shift  and amplitude difference between the vibration shakers during the test.

Simultaneous impact on the object on several axes has a number of advantages:

• It saves time. There is no need to run the test on different axes consecutively. The test time is also decreased because you do not have to re-position the object on the shaker.
• It proves to be a better imitation of actual operating conditions the object undergoes.

Single-axis multishaker tests are usually run when it is not possible to mount the object on one shaker due to the size of the object.

In single-axis tests it is recommended to fix the object on the shaker in such a way that there is room for some asynchronous vibration (in other words, there is some phase shift between the shakers, which doesn’t allow damaging the shaker or the object).

Note: on resonant frequencies of the object or fixture, the phase shift may increase.

RL-C21 and RL-C25 vibration control systems apply computation of transfer-function matrix to maintain the phase and amplitude in multishaker tests, through control of shakers interaction and non-linearity of the vibration set.

Tests available in Multishaker mode:

Multishaker tests mode parameters for RL-C21 and RL-C25:

•Number of control channels: 2 – 8.
•Number of control outputs: 2 – 8.
•Number of shakers: 2 – 8.
•Frequency range: 0.1 to 20000 Hz.
•Maximum number of control lines: 13000

The systems can run multishaker tests on one or several axes.

Phase shift is not more than 1°.

In Sine mode it is also possible to set the phase difference between the shakers (from 0° to 180°), which the system will maintain during the test.

In Random test, FDR and Shock tests the control is in-phase, i.e. the minimum phase shift will be maintained.

In Random test mode, the system can control :

Identical signals on identical profiles for each shaker
•Signals of different waveform, but with the same frequency and PSD.

In the first case, the control of shakers is in-phase.

In the second case, the shakers will run the same profiles with a different waveform.

In Random test, FDR and Shock the systems can run different profiles.

I.e. each shaker runs its own test profile, different from the others in frequency, amplitude, shape, etc.

In Shock mode, the software synchronizes different profiles by acceleration peak.

For Random test, FDR and Shock it is also possible to set a control filter of start and end frequency.

The lower frequency of the filter can be determined automatically depending on the shaker lowest operation frequency, or specified by the user.

For any test type,  the “number of averaging” parameter is specified.

When the parameter is increased, the  work of the control algorithm is more stable, but its reaction is slower.

By default the number of averaging is 8 to 10.

This values help to keep the right balance between stability and reaction time of the control algorithm in most cases.

For each test, it is possible to set up the control factor.

This parameter is responsible for the rigorous selection of the matrices based on their singularity. By editing this parameter, the user can adjust the sensitivity of the control algorithm (the higher the parameter, the lower is the sensitivity of the control algorithm to the singularity of the matrix).

This parameter is in direct correlation with the number of shakers in the set. For instance, for 2-3 shakers, it will be 10, for 4-5 shakers 20-30 will be a better fit, for 6 and more – 40.

Absolute compression rate for Random test, FDR and Shock

This parameter limits the rate of control filter tuning. It is specified in dB/s.

Same as the control factor, it has a direct correlation with the number of shakers in the set.

For sets containing 4 and more shakers, it is usually increased to 20 dB/s (sometimes to 30 dB/s) to provide the quickest and most efficient operation of the control filter.

See more education materials
VisProbe SL

VisProbe SL

Other equipment