SKF CMSS 785 Series, User Manual

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4.1.3 Probe mounting
Ensure that the probe mounting location satisfies the following environmental and installa-
tion requirements.
Environmental conditions
• Probe temperature: must always be in the range between –40 to 177 °C.
• Vibration levels at the probe: must be 10 m/s
2 or less (10 to 150 Hz), noting however that if
the sensor vibrates, an accurate measurement cannot be made.
• Locate the probe so as to avoid immersing it in fluid (particularly the probe cable/cable exit)
Installation conditions
• The probe must be installed on a surface or bracket with adequate rigidity, that will not
allow the probe to vibrate. If the probe vibrates, an accurate measurement of the target/
shaft will not be possible.
• The field radiating from the probe tip extends out from the probe tip in all directions. To
maintain the nominal characteristic, a minimum target diameter of 15 mm, centered on
the probe is required.
• Similarly, when placing probes near to each other, separate the sensor tips as shown
below. If they are placed too close together, the probes will interfere with each other.
∅
20 mm
or more
30 mm
or more
40 mm or more
Target
Target
• For the preferred detailing of the probe mounting, refer to the installation examples 1–3
below. If the mounting or other metal object other than the target is near the probe/within
the field, the measurement will be affected.
To ease probe mounting and adjustment, various accessories are separately available:
• CMSS VZ-03A probe mounting bracket (versions for 5 and 8 mm probes, metric/UNF threads)
• CMSS VZ-10A sensor sleeve (for 8 mm reverse mount probes)
• CMSS VZ-05A sensor housing (usable with 5, 8 mm and reverse mount probes)
See section 5.1 for examples of how these mounting accessories can be utilized.
If it is unavoidable to install the probe in a non-ideal way (examples 4 to 7), some guidance is
given on the likely effect. In case of any doubt, where possible, perform an in-situ check of
the actual characteristics of the installation.
Be aware that the probe/driver output will not reduce to zero volts, and that the probe should
not be used/relied upon in situations where the gap between probe and target is small
(0.25 mm or less, example 8).
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