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CI?!KB?BHIDB!@MZ@DI?DEIN!JIK?BDEC!XBNY@^!@F!CIHB!JM@D!ZB
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2.9.3
Electromagnetic Interference (EMI)
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JB?D@! DF! ZB! IGGBCDBY! Z_! BTDBH?IN! @FMHCB@#! $?! DLB@B
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•
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2.9.4
Ground Loops
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HB@MNDE?K! KHFM?Y! NFFA! CIM@B@! CMHHB?D! DF! eFW! DLHFMKL
DLB! E?@DHMJB?D! 7(! @EK?IN! NBIY@! I?Y! DLB?! ZICU! DLHFMKL
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FG! DLB! DWF! E?@DHMJB?D@#! &LE@! `FNDIKB! WENN! ZB! IYYBY! DF
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JBI@MHBJB?D#
Signal Leads
Instrument 1
Instrument 2
Ground
Loop
Current
+(,-%$!./.01
2)3$%!4(*$!5%)-*6!4))#7
.EKMHB! -,-8! @LFW@! LFW! DF! CF??BCD! @B`BHIN! E?@DHMJB?D@
DFKBDLBH!DF!BNEJE?IDB!DLE@!D_AB!FG!KHFM?Y!NFFA!AHFZNBJ#
PBHB^! F?N_! F?B! E?@DHMJB?D! E@! CF??BCDBY! DF! AFWBH! NE?B
KHFM?Y#
>HFM?Y! NFFA@! IHB! ?FD! ?FHJINN_! I! AHFZNBJ! WEDL! E?@DHM,
JB?D@! LI`E?K! E@FNIDBY! 7(! DBHJE?IN@#! PFWB`BH^! INN
E?@DHMJB?D@! E?! DLB! DB@D! @BDMA! JI_! ?FD! ZB! YB@EK?BY! E?
DLE@! JI??BH#! 3LB?! E?! YFMZD^! CF?@MND! DLB! JI?MIN! GFH
BICL!E?@DHMJB?DIDEF?!E?!DLB!DB@D!@BDMA#
"#$%&'(!)
"#$%&'()*
Instrument 3
Power Line Ground
898:
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