Table of Contents
Related Manuals for PCE Instruments PCE-VM 25
Summary of Contents for PCE Instruments PCE-VM 25
- Page 1 User Manual VIBRATION TESTER PCE-VM 25 Version 1.0 © PCE Instruments Address:East Room 306,3th Floor,1st Building,Shenhua Industrial Park,Meihua Road, Futian District,Shenzhen City Tel:0755-32978297 Email:hj@pce-instruments.cn...
- Page 2 PCE Instruments contact information Germany France PCE Deutschland GmbH PCE Instruments France EURL Im Langel 4 76, Rue de la Plaine des Bouchers D-59872 Meschede 67100 Strasbourg Deutschland France Tel: +49 (0) 2903 976 99 0 Téléphone: +33 (0) 972 3537 17 Fax: +49 (0) 2903 976 99 29 Numéro de fax: +33 (0) 972 3537 18...
-
Page 3: Table Of Contents
6.1. Measurement Value Display ..................6.2. Selecting the Display Quantity ..................6.3. Measurement Point Detection ..............6.3.1. Reading the VMID Data with the PCE-VM 25 ................6.3.2. Entering the Measurement Point Text ..............6.3.3. Editing and Deleting Measurement Point Data .................... -
Page 4: English
The PCE-VM 25 operates with a piezo ceramic shear accelerometer. Piezoelectric vibration transducers are characterized by high precision and resolution with great robustness. The accelerometer of the PCE-VM 25 has an integrated electronic circuit for impedance conversion in accordance with the IEPE standard. At the base of the sensor a magnet has been integrated for mounting to the measurement point. -
Page 5: Measuring Ranges
The Figure shows the block diagram. The PCE-VM 25 supplies the IEPE Sensor with 2 mA constant current. At the sensor output, a vibration acceleration proportional AC voltage arises, which is amplified in the instrument to produce an optimum level. The gain switch-over takes place automatically. The subsequent analogue/digital converter is a Sigma-Delta converter with 24 bit resolution. -
Page 6: Vibration Velocity
RMS. Besides the frequency range of 10 to 1000 Hz, the PCE-VM 25 has a further frequency range for vibration severity measurements from 2 to 1000 Hz. This is suitable for measurements on slow running machines with a nominal speed of less than 120 min-1 and on reciprocating engines according to ISO 10816-6. -
Page 7: Vibration Displacement
Due to these restrictions, displacement measurements should only be applied where acceleration or velocity is not capable of delivering the desired assessment. The PCE-VM 25 measures the vibration displacement from 5 to 200 Hz. The frequency response diagram is shown in Figure 6. The curve ends at 200 Hz because even in the case of a fully modulated sensor only single digit measurement values still occur. - Page 8 Figure 7: Frequency response curves for displacement (RMS) The maximum displacement of the PCE-VM 25 that can be measured is around 60 mm (RMS). It yields a frequency independent modulation range of up to 10 Hz. At higher frequencies the measuring range limits for acceleration of around 240 m/s² take effect.
-
Page 9: Rolling Bearing Parameters K(T)
3.6. Rotational Speed Alongside vibration the PCE-VM 25 measures the rotational speed by means of an inbuilt contactless optical sensor (Figure 34 on page 25). To enable this, the instrument needs to be aligned with the rotating part, for which a laser pointer can be used to help with the positioning. -
Page 10: The Batteries
4.1. Inserting the Batteries The PCE-VM 25 is supplied by three alkaline standard cell type AAA (LR03) batteries. NiMH batteries (HR03) may also be used. The minimum energy requirement of the PCE-VM 25 enables maximum utilization of the batteries. Attention: Please switch the instrument off before changing the batteries. When switched off, the contents of the memory are stored for a few minutes, without need of the batteries, and the internal clock continues to run. -
Page 11: Battery Display And Battery Type
If the PCE-VM 25 is connected to a USB port, it will be supplied by the USB voltage in order to spare the batteries. In this case, “external” is displayed on the screen instead of the battery level indicator. -
Page 12: Preparation Of Measuring Points
5. Preparation of Measuring Points 5.1. General Information on Measurement Point Choice When monitoring machines it is important to take measurements under the same operating conditions, at the same measurement point. Choosing the suitable measurement point is therefore decisive. Where possible, qualified staff experienced in machine monitoring should be called upon. It is generally advisable to record machine vibrations near to their source. -
Page 13: Vmid Measurement Point
5.3.1. How the VMID Measurement Point Functions The PCE-VM 25 is equipped with an electronic measuring point detector. Metra offers a type VMID measurement point, which is made of magnetic stainless steel and has aninbuilt memory with an individual serial number. -
Page 14: Selecting The Display Quantity
Note: When saving measurement values (chapter 6.4) the RMS and peak value are always saved both irrespective of the currently selected setting. If the sensor locates a VMID measuring point which is already saved in the PCE-VM 25 memory, in order to prevent unintentional switch-over, a warning signal will be displayed when the measurand changes (Figure 19). -
Page 15: Entering The Measurement Point Text
Figure 20: Newly recognized VMID 6.3.2. Entering the Measurement Point Text If a measurement point has not yet been assigned a text, press the▼ key to reach the text edit menu (Figures 20 and 21). A space of two rows consisting of 10 characters each is assigned for each measurement point text. -
Page 16: Editing And Deleting Measurement Point Data
Figure 23: Deleting an ID record In the same way, the entire measurement point data can be deleted as a whole by selecting “Erase all Point IDs” in the “ID Menu”. The PCE-VM 25 memory can store data for a maximum of 1600 measurement points. -
Page 17: Viewing Saved Measurement Values
To deliver the service staff on site a report about the periodic changes in vibration severity and consequently the previous history of the measurement point concerned, the PCE-VM 25 provides a graphical trend display. The prerequisite for retrieving graphical trends is placing the sensor on the relevant VMID. The trend display is obtained by pressing the F1 key (Figure 24). -
Page 18: Deleting Saved Measurement Data
K(t) measurements are only intended for use in conjunction with a VMID measurement point. The start / reference values RMS and peak of values which have been measured on the new rolling bearings are required for calculating K(t). These start values are saved in the PCE-VM 25 together with the measuring point ID. Place the sensor on a VMID measuring point of the relevant bearing. - Page 19 Figure 27: K(t) mode with newly detected VMID If the VMID point ID has been saved but not the K(t) start values, then this is the next step. By pressing the ▼ key the currently measured RMS RMS(t) and peak value Peak(t) are saved as K(t) the start value RMS(0) and Peak(0) (Figure 28).
-
Page 20: Frequency Analysis
6.9.1. Settings In addition to the measurement of RMS and peak values the PCE-VM 25 has a simple frequency analysis function. To access this function, switch to the main menu by pressing F3 and select the menu option “Frequency analysis (Figure 31). - Page 21 Figure 31: Frequency analysis menu The peak value spectrum of the currently measured acceleration or velocity is shown in Figure 32). Figure 32: Spectral display for acceleration and velocity The vertical axis of the diagram represents the peak value with linear scaling and the horizontal axis the frequency. The diagram shows 125 lines. The frequency range in display can be halved by pressing F1 and doubled by pressing F2.
-
Page 22: Fft Memory
Press F1 to delete the displayed spectrum from the memory. Saved Spectra can also be transferred via USB to the PC software VM2xMDB. 6.10. Rotation Speed Measurement The PCE-VM 25 has an inbuilt RPM laser sensor for contactless measurements. This is located in the lower part at the back of the instrument (Figure 34). EN - 22... - Page 23 Figure 34: Rotation speed and temperature sensor, laser pointer For taking rotation speed measurements the rotating part needs to be marked with a piece of reflective film. Self-adhesive reflective film can be purchased from Sick, for example the material REF-PLUS. Press the ◄...
-
Page 24: Temperature Measurement
Figure 36. Every infrared temperature sensor shows a dependency on the emissivity of the measuring object. The PCE-VM 25 is calibrated for an emission level of 1. With some materials, such as Aluminum, this can cause measurement errors. -
Page 25: Measurement Evaluation With Standard Values
7. Measurement Evaluation with Standard Values To be able to derive statements from the measured vibration velocity values about the condition of a machine, experience is necessary. If experienced personnel are not available, in many cases one can refer to the ISO 10816 recommendations. In these sections of the standard, the vibration severity zone limits for various machine types are defined, which can provide an initial evaluation of a machines maintenance condition.The four zone boundary limits characterize the machine in categories according to vibration severity: A: New condition... - Page 26 In part 3 of ISO 10816, revised in 2009, the zone borders are specified for vibration severity of machines with a power of 15 kW to 50 MW (Table Table 2: Vibration Severity classification in accordance with ISO 10816-3 Part 7 of the ISO 10816 deals specifically with rotodynamic pumps (Table 3). Table 3: Classification of the vibration severity of rotodynamic pumps in accordance with ISO 10816-7 EN - 26 Address:East Room 306,3th Floor,1st Building,Shenhua Industrial Park,Meihua Road, Futian District,Shenzhen City...
-
Page 27: Setting The Date And Time
To exit the menu press OK followed by F3 repeatedly. 9. Calibration The PCE-VM 25 comes with with a factory calibration, which is traceable to the reference standard of the Physikalisch-Technischen Bundesanstalt (PTB). The calibration is only valid with the supplied vibration transducer. - Page 28 40). This is done using the magnetic base. Press OK. Figure 40: Calibration menu The PCE-VM 25 is now ready for the reference vibration signal. It displays the measured acceleration (Figure 41). EN - 28 Address:East Room 306,3th Floor,1st Building,Shenhua Industrial Park,Meihua Road, Futian District,Shenzhen City Tel:0755-32978297 Email:hj@pce-instruments.cn...
-
Page 29: Sensor Check
10. Sensor Check The PCE-VM 25 input is designed for use with a low power IEPE accelerometer. These sensors are supplied by constant current, which produces a positive DC voltage potential at the output. Due to this DC voltage an assessment can be made of the sensor‘s operating condition. The PCE-VM 25 detects three operational conditions: <... -
Page 30: Reset Key
12. Reset Key If it occurs that the PCE-VM 25 does not respond to the press of any button, press the reset key to restart the instrument. The reset key is reached with a thin object through the aperture next to the type label (Figure 45). - Page 31 6. Within the PCE-VM 25 “Instrument Settings” select the option “Update Firmware” and confirm the warning and subsequent hint messages by pressing OK. By carrying out this step the old firmware is deleted. The PCE-VM 25 will then indicate that it awaits new firmware data from the USB port (Figure 49).
-
Page 32: Spezifikationen
1 Spezifikationen Displayed measurand True RMS and peak value (crest value) of vibration acceleration, velocity and displacement, K(t) rolling bearing parameters, rotation speed, temperature Measuring range at defined accuracy Acceleration: 0.1 – 240 m/s² Velocity: 0.1 – 1000 mm/s; > 40 Hz frequency dependent Displacement: 0.01 –... -
Page 33: Limited Warranty
VMID measuring point, read through sensor base Coding 16 digit unique hexadecimal number Measuring point ID memory (PCE-VM 25) 1600 measuring points with serial number and text Mounting the VMID Mounting the VMID Mount with two part adhesive, e.g. LOCTITE... -
Page 34: Declaration Of Conformity
Declaration of conformity EN-34 Address:East Room 306,3th Floor,1st Building,Shenhua Industrial Park,Meihua Road, Futian District,Shenzhen City Tel:0755-32978297 Email:hj@pce-instruments.cn... - Page 35 Specifications are subject to change without notice. Address:East Room 306,3th Floor,1st Building,Shenhua Industrial Park,Meihua Road, Futian District,Shenzhen City Tel:0755-32978297 Email:hj@pce-instruments.cn...
Need help?
Do you have a question about the PCE-VM 25 and is the answer not in the manual?
Questions and answers