Difference between revisions of "NVGate Torsional"

Jump to navigation Jump to search

NVGate Torsional (view source)

Revision as of 17:33, 8 May 2020

4,843 bytes added ,  17:33, 8 May 2020
no edit summary
Line 2: Line 2:
NVGate  propos a comprehensive suite for torsional measurements and analyses.It addresses most of the torsional, cyclic and rotational resonances issues.  
NVGate  propos a comprehensive suite for torsional measurements and analyses.It addresses most of the torsional, cyclic and rotational resonances issues.  
For both R&D and diagnostics, the latest torsional feature the OROS analyzer <u>the solution</u> for '''transmissions, engines '''and''' electric machinery vibration analysis'''.
For both R&D and diagnostics, the latest torsional feature the OROS analyzer <u>the solution</u> for '''transmissions, engines '''and''' electric machinery vibration analysis'''.
Overview
1.4.2. Frequency to RPM converter (Torsional inputs)
Scope
On reciprocating machinery (diesel engine, pump) or any acyclic rotating devices (generator,
compressor), the cause of vibrations often comes from the non-linearity of the angular speed.
The analysis of the instantaneous angular speed inside each shaft revolution provides essential
information. Such information are helpful for vibrations reduction during prototyping or even
for source identification while doing service diagnostics.
The common way to measure such instantaneous velocity is
to install a coding wheel or a rotary encoder on the shaft.
Then the rate of pulse delivered by such device is directly
proportional to the RPM speed during the last pulse interval.
This type of measurement needs a specific conditioner
(usually an external box) which transforms the pulses train in
a continuous voltage proportional to the RPM.
Such devices are expensive, lead to more cable, are often
OROS F200 953-9 NVGate®® Version 6.00 release note Page 18/37
limited to 2 probes and so on. But the main inconvenience is the phase error they introduce
due to their internal response time.
New option
In the continuity of its specialization in the rotating machinery measurement and analysis
OROS propose with NVGate® V6.00 an integrated frequency to RPM converter which avoids
the above-mentioned inconveniences.
The ORNV-FRC is an option of NVGate® V6.00. It transforms each external Synch input in a
frequency to RPM converter (allows handling up to 6 torsional/acyclic inputs at a time). This
integrated converter benefits of the high accuracy of the 3-Series analyzers Ext. synch inputs
(over sampled up to 6.4 MHz). As a matter of fact the sampling of such pulse rate must be
very accurate in order to avoid speed jitter on the result.
Operation
The ext. synch input can be used as a:
1. Trigger -> provides edge detection events
2. Conventional tachometer -> provides RPM at each
revolution.
3. Torsional converter (option) -> provides
instantaneous RPM as a signal.
By selecting the third option (Torsional) in the Mode
Setting, the ext. synch is made available as a standard input
providing the RPM signal.
The other settings to update are:
· the number of pulses/rev.
· Average size which acts as rpm smother when the
jitter is too high.
· Min/max speed which operates the same as for the
other tachometers.
· The missing teeth (0, 1 or 2) will create virtual pulse
when detecting missing pulses (1or 2 consecutives)
Pulses train
Converted RPM
OROS F200 953-9 NVGate®® Version 6.00 release note Page 19/37
· At least the filter which let you integrate or differentiate the RPM speed to get
respectively plane angle deviations and angular accelerations for the analyses.
Analyses
The instantaneous signals are available for numerous analyses. The main tow ones are:
· The non cyclic behavior of a shaft which is analyzed by the order analysis processing
providing order profiles and the time domain analysis for in revolution RPM profiles.
· The torsional behavior of a shaft (crankshaft, alternator) or a driving belt (service belt)
being excited by its acyclic motion. In such a case the phenomena are analyzed order by
order using the cross-phase tracking capabilities of the SOA Plug-in. In this case 2 or
more torsional inputs are used: in different location of the shaft or on each pulley driven
by the belt.
On-line
In the on-line mode the torsional inputs appear
as additional in the channels connection dialog
box. They are identified as Tors. x from the
Signal Op. resource (not visible in the ASB).
These signals can be dispatched exactly as the
standard inputs ones; recorded, analyzed and
monitored with the TDA plug-in.
The torsional inputs may be recorded as it or the
source pulses can be recorded also.
Post-processing
For post-analysis purposes, the way to operate depends on the type of recorded signal:
· If the converted signal (Tors x) have been recorded, the post analysis is exactly like for
the usual recorded inputs:
· if the pulses have been recorded and not the converted signal, a new resource module
called Signal Operation is then available for this conversion.
OROS F200 953-9 NVGate®® Version 6.00 release note Page 20/37
· The conversion setup is available from the ASB. It is
identical to the on-line one:
· At least the Tors. x signal (converted to angular
velocity (or acceleration or deviation) is available from
the track connection dialog:
Specifications
The FVC option features the following main specifications:
· Number of pulses/rev: 1 to 1024
· Max pulse frequency: 40 kHz, resolution 200 ns
· Max angular speed:
Pls rev
RPM
/
2400000
max = eg: 12 000 RPM with 200 Pls/rev
· Missing teeth management: 1 or 2 consecutive teeth.
· Available filters: HP, LP; BP, SB, Int, double Int, differentiation


===Angular sampling for SOA analysis===
===Angular sampling for SOA analysis===
Retrieved from "https://wiki.oros.com/index.php?title=Special:MobileDiff/3924"

Navigation menu