(LV-7000 series vs MP-900/9000 series + FV-1500)
In the following application, LV-7000 series (Laser Doppler Surface Velocity Meter), and MP-900/9000 series + FV-1500 are used to measure rotation speed unevenness and rotation resonance. Compare the products included in each system and the results obtained, and select the suitable method depending on your application.
Measurement system used
1. LV-7000 series
Laser Doppler Surface Velocity Meter
2. MP-992 + FV-1500
Electromagnetic rotation detector + High speed FV Converter
3. MP-981 + FV-1500
Magneto-electric rotation detector + High speed FV Converter
System configuration
| Model name | Product name | Remarks | |
|---|---|---|---|
1 |
LV-7000 series | Laser Doppler Surface Velocity Meter | Velocity output ± 10 V |
2 |
MP-981 | Magneto electric rotation detector | Detectable frequency range 1 Hz to 20 kHz |
3 |
MP-992 | Electromagnetic rotation detector | Detectable frequency range 400 Hz to 100 kHz |
4 |
FV-1500 | High speed F/V Converter | It converts to frequency by using the interval time between pulses of the input signal and outputs a voltage proportional to the frequency of the input signal. |
5 |
DS-3204 | Data Station | 4ch 40 kHz Main unit |
6 |
DS-0350 | Recording function | |
7 |
OS-2000 series | Time series data analysis software |
Advantage/disadvantage for each method
| LV-7000 series | MP-981 + FV-1500 | MP-992 + LV-1500 | |
|---|---|---|---|
| Sensor | Non-contact (Laser light） | Non-contact (ferromagnetism gear required) |
Non-contact (ferromagnetism gear required） |
| Gear/ gear cutting disk for detection | Not required | Required | Required |
| Sensor fixing jig | Required | Required | Required |
Detection distance (from a target to a sensor) |
200 mm (from the laser projecting port) |
0.5 to 1 mm (from the tip) | 0.5 to 1 mm (from the tip) |
| Detection from 0 speed | Available (with DC offset) | Not available (without DC offset) |
Not available (without DC offset) |
| Detection until around 0 speed | Available(with DC offset) | Not available(without DC offset) | Not available (without DC offset) |
| Detection of reverse rotation | Available | Not available | Not available |
| Response・resolution | High response/high resolution | - | - |
Influence of RRO (rotatable run out) |
Big | Small | Small |
| Other features | •The speed may not be completely zero on the analog output when DC offset is set at zero speed. •Costly |
•It has resistant to disturbance. •Relatively inexpensive |
•It has resistant to disturbance. •Relatively inexpensive •Cannot detect low rotation |
Comparison of output waveform
*MP-992 Electromagnetic rotation detector: detectable from around 1000 rotation. Low rotation speed cannot be detected by the MP-992. It is not suitable for this example.
Comparison of detection result, LV-7000 and MP-981
Detection result of rotation speed (Total waveform)
Revised:2018/7/13
