Several questions about the Bentley 8mm probe
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1. The Bentley probe used in our factory is 8mm in diameter, and the preamplifier is from the 990 series. During the vibration adjustment last time, the manufacturer said to set it to -9.75V; why is this a negative voltage? 2. When looking up information online, the value given is -10V; how was -9.75 determined with such precision? If the zero-point gap of the probe is 1.27 mm, then 9.7 V seems to be the appropriate value based on the graph
There’s no need to worry about this; 9.75 and 10V are both roughly in the middle of the probe’s linear range. Think about what the maximum value of your interlock is in micrometers
Yes, the typical value for chain length is between 80–100 μm. Based on the probe’s characteristic curve, a zero voltage of between -6 and -11 should be acceptable.
When looking at the gap-voltage graph, generally the linear portion is taken, or the midpoint of the roughly linear region; the voltage corresponding to that point is then used as the value to adjust
The installation voltage range for probes measuring general vibration is relatively wide, while that for those measuring displacement is within a narrower allowable range. Just make sure the OK light is working properly.
There’s no need to worry about this; 10±1V will work just fine
For vibration: -10 +-0.5; as for displacement, it depends on what the system’s zero voltage is – the usual setting is -9.75. Of course, if you set the zero voltage to -10, you can change it to -10 in the Bentley system
I would like to ask the original poster: how can one determine the size of the gap based on the output voltage (on the vertical axis) and the vibration value (on the horizontal axis)?
Hello Haiyou: How can one determine the gap size based on the output voltage (on the vertical axis) and the vibration value (on the horizontal axis)? I earnestly request your guidance. Thank you