Grounding Concept - holthausen elektronik ESW-small-Compact User Manual

Electronic Vibration monitoring Unit
ESW ® -small-Compact

5. Grounding concept

vibration
control unit
vibration control unit ground
local
vibration control unit ground
If an isolated installation is not specially requested, usually through the attachment with
screws each case is connected to the local machine ground.
Inside the ESW ® -small-Compact the case potential, the cable shield and the internal signal
ground could be connected with each other by choice (see 13).
In big facilities with considerable energy consumption and distances between the machines
could such big potential difference be build up, that substantial balancing current on the
ground network will occur. Dependent on intensity of such currents is arising of interference's
or damaging of the unit the result!
Potential differences could also arise on machines, with small distances not clear crossing of
ground potential for example painted color or movable parts like suspension mounting.
Energetic high frequency interference energy could be added to the measurement signal-
wire by inductivity or trough capacity that could change the real existing measurement value!
In this way, for example parallel going elements could act as coupling-capacitor and winded
up grounding cable could act like a cut off choke.
Memorize: Earth connection is not the same everywhere!
 Check the situation
 Plan the grounding concept
 Select the facility / realization
optional
connection box
shield
signal ground
connection box ground
shield
signal ground
connection box ground
local
6
holthausen
elektronik GmbH
main control box
with power supply
+Ub
-Ub
main control
box ground
local
main control box ground