HBM SK12, Mounting Instructions, Page: 33 / 48

33
SK5, SK6, SK12
HBM A0842-2.0 de/en
20.1 Hints for measurements
In the case of strain gauge measurements it is advisable to use the full bridge
circuit since in that case there will be the least influence from the slipring
transmission, compared to half or quarter bridge configurations. For very
precise measurements the 700 Ω strain gauge full bridge is preferred, howe-
ver, even with 350 Ω or 120 Ω full, half, or quarter bridges the errors will be
comparatively small.
20.2 Mass or earth connection
In order to avoid errors or disturbances from static charges the rotor shall be
properly earthed. For that purpose one connects a free slipring and the cor-
responding brush with the machine earth. Additionallythe stator housing earth
(soldertag between connections 3 and 4 and 6 and 7 resp.) shall be connec-
ted with machine earth.
lf the operating voltage zero ( ) of the amplifier shall also be connected to
this earthing point one should do this by soldering the cable screen to the
earthed solder tag of the stator. No other earth connection shall be used in or-
der to avoid earht loops (see fig. 5.1).
Abb. 5.2: Mounting without mounting plate