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 con-
dition. The four zone boundary limits characterize the machine in categories accord-
ing to vibration severity:
A: New condition
B: Good condition for unrestricted continuous operation
C: Poor condition - allows restricted continued operation only
D: Critical condition - Danger of damage to the machine.
v
ef
f
1
0
–
1
00
0
H
z
45 mm/s
28 mm/s
18 mm/s
14.7 mm/s
Zone
C/D
4,5 – 14,7
mm/s
11.2 mm/s
9.3 mm/s
Zone
B/C
1,8 – 9,3
mm/s
7.1 mm/s
4.5 mm/s
Zone
A/B
0,71 – 4,5
mm/s
2.8 mm/s
1.8 mm/s
1.12 mm/s
0.71 mm/s
0.45 mm/s
0.28 mm/s
D
Risk of machine damage
C
Restricted continued operation
B
Unrestricted operation possible
A
Newly commissioned machine
Table 1:Typical zone limit values for vibration severity according to ISO 10816-1
In the standard it is pointed out that small machines, for example electric motors
with a power rating of up to 15 kW, tend to lie around the lower zone limits,
whereas large machines, for example motors with flexible foundations, lie around
the upper zone limits.
27
