II - DCE FEL ČVUT v Praze

Mechanical Configuration of an Automation System with SIMATIC S7 Ex Modules
Table 1-8 Working on systems to type of protection: EEx de [ib] T5 .. T6
Type of
protection of
apparatus used in
system
1-44
Type of work to
be carried out
EEx ib Zone 1 Zone 2
Opening the
housing, Ex i/e
housing only
Connecting/
disconnecting
lines
Current, voltage
and resistance
measurement
Work within Additional
requirements and
notes
Allowed Allowed If no other
apparatus is in the
housing
Allowed Allowed
Allowed with
certified apparatus
Allowed
Soldering Prohibited Allowed if
soldering
temperature lower
than ignition
temperature
EEx e Zone 1 Zone 2
Opening the
housing, Ex i/e
housing only
Connecting/
disconnecting
lines
Current, voltage
and resistance
measurement
Allowed Allowed If no other
apparatus is in the
housing
Not allowed
unless in
de-energized state
Voltage
measurement with
certified apparatus
only
Only in
de-energized state
and if no risk of
explosion
Voltage
measurement with
certified apparatus
only
Soldering Prohibited Allowed in
de-energized state
if soldering
temperature lower
than ignition
temperature
I/O Modules with Intrinsically-Safe Signals
C79000-G7076-C152-04