Ametek CEM/Humox, Руководство пользователя

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Installation
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3-11
The (N) terminal is not internally grounded, nor needs to be. The system
will operate normally regardless of what AC input terminal (L or N)
that AC Line or Neutral is connected to, or, if there is a Neutral used
at all (i.e. 208 VAC US power connection).
Mains supply connections to the control unit are as follows:
Line - Line connection
Neutral - Neutral connection (USA)
Chassis Stud - Equipment ground (protective conductor)
Use the 1/2” conduit entry hole in the control unit for AC mains supply wiring. Use
the chassis stud next to the 1/2” conduit entry hole for equipment ground (protec-
tive conductor).
EMC grounding, shielding, and noise protection
For EMC purposes, under no circumstances should you leave cable
shields disconnected at one end or both ends of the cable (sensor or
control unit or other device).
You must use twisted-pair cable in rigid metal conduit or use twisted pair cable with
an overall braided shield. All cable shields or conduits connecting to the control
unit must be chassis grounded.
EMC Grounding Method
•
Shield Ring Method
Connect all shields for that conduit entry (other than power) to a supplied shield
terminal ring (see Figure 3-11). This shield ring is a stainless steel ring with a
metal tab. Place the shield ring under the conduit nut. Crimp the shields from
all cables for that conduit entry to a 1/4” female quick disconnect, then push it
onto the tab that sticks out of the conduit shield ring. Keep shields as short as
possible.
•
Ground Stud Method
Connect all cable shields for that conduit entry to the grounding stud closest to
that conduit entry hole.