7
TRUNKGUARD™
Series Fieldbus Device Couplers
(Zone 1 Locations)
TG300
may be made only while the trunk is de-energized
or under normal Zone 1 working practices (typically,
under local supervision by gas detectors, etc). Spur
connections can be made while the TG300 unit is
energized only if the DISCONN Key is activated
and only the YELLOW LED is ON for that spur.
Alternatively, the whole segment should be de-
energized.
If the GREEN LED is ON at the same time as the
YELLOW LED is ON, the segment has not been
de-energized and no wiring work is permitted
without removing power to that segment. If the RED
LED is ON, then follow the steps in the
Testing and
Troubleshooting
section.
Field devices should be certified/approved for use
in hazardous areas (e.g. EEx d in Zone 1) and
are typically connected using armored, braided or
toughened-sheath cabling. MooreHawke cable glands
are EEx d and EEx e approved, but need to be sized
for the appropriate armored or toughened cable.
Earth continuity plates are provided, bonded to an
external earth stud.
DISCONN Key
The DISCONN Key contains the magnet used
to operate the magnetic interlock which permits
individual fieldbus devices to be de-energized and
worked on without de-powering the entire segment.
You must have the DISCONN Key fully inserted into
the spur receptacle for the spur to be de-energized.
Recommended Ground Wiring
Practices
Moore Industries recommends the following ground
wiring practices:
• Any MooreHawke product in a metal case or
housing should be grounded.
• The protective earth conductor must be
connected to a system safety earth ground
before making any other connections.
• The maximum length of unshielded input and
output signal wiring should be 2 inches.
• Some local electrical codes or facility
practices may require the Shield to be
connected to Ground at more than one
location. Follow proper local guidelines.
Fieldbus segment cable Shields for spurs and
trunks are gathered together in the device coupler
and then wired through the trunk cable to the next
device coupler and eventually to the fieldbus power
conditioner. Single point Grounding is recommended
for segment shields. Grounding of the segment shield
usually occurs at the power conditioner.
Содержание Hawke TRUNKGUARD Series
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