
WARNING
Lack of equipotential bonding
Danger of explosion through compensating currents or ignition currents through lack of
equipotential bonding.
For devices of intrinsic safety "db", "ec", "tb" or "tc" which are operated in a non-intrinsically
safe circuit, observe the following:
● Connect the device to the system via the equipotential bonding terminal.
Note: For devices of the intrinsic safety "ia", "ib" and "ic" type of protection, which are operated
in an intrinsically safe circuit, connection to the system via the equipotential bonding terminal
is not required.
WARNING
Improper laying of shielded cables
Risk of explosion through compensating currents between hazardous area and the
non‑hazardous area.
● Shielded cables that cross into hazardous areas should be grounded only at one end.
● If grounding is required at both ends, use an equipotential bonding conductor.
WARNING
Connecting device in energized state
Risk of explosion in hazardous areas.
● Connect devices in hazardous areas only in a de-energized state.
Exceptions:
● Devices having the type of protection "Intrinsic safety Ex i" may also be connected in
energized state in hazardous areas.
● Exceptions for type of protection "Increased safety ec" (Zone 2) are regulated in the
relevant certificate.
Connecting
6.1 Basic safety instructions
SITRANS P320/P420 with 4 to 20 mA/HART
66
Operating Instructions, 11/2019, A5E44852162-AC