Typical Mils Vibration Question

[mpeck1982]

Can mils be a positive and a negative number? I've seen positive all the time. However by my operators rounds and readings, they are reporting negative. If I have a trip/alarm setpoint of (5/10)-mils for compressor vibration on a chiller, does that typically account for both magnitudes?

 

[electricpete]

When describing vibration magnitude, one would not normally use negative number.
However when describing thrust (axial) position of shaft, one might use negative number.

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(2B)+(2B)' ?