JUMO 902820 PROCESStemp RTD Temperature Probe for Process Technology (Also with ATEX Approval) Ex e Operating Manual User Manual

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The temperature classes and safety reserves apply equally to both protection types, and the temperature
development in the terminal head (if used with a built-in transmitter) must also be taken into account.

For operation in Zone 0 (G) or 20 (D), type “d” protection “Flameproof enclosure” is by no means sufficient
by itself! Two independent protection types and/or zone separation are required here.

In the presence of a potentially explosive atmosphere, the terminal head and/or connection terminals must
not be opened in the energized state unless the “Intrinsic safety” (Ex “i”) type of protection has also been
implemented.

5.4 Increased safety, Ex “e” protection
This refers to measures taken to increase the safety level by reliably preventing unacceptably high
temperatures and the generation of sparks or arcing, in both internal and external parts of electrical
apparatus that does not generate such temperatures, sparks or arcing in normal operation or in the event of
a fault.

It is not mandatory to connect the versions with increased safety to intrinsically safe circuits, however, it must
always be ensured that the rise in temperature of the thermometer remains limited in every operational or
fault situation, as was described in detail in Section 5.1. and demonstrated by case studies.

The temperature classes and safety reserves apply equally to both protection types, and the temperature
development in the terminal head – if used with a built-in transmitter that has been certified separately (Ex
“i”) – must also be taken into account.

For operation in Zone 0 (G) or 20 (D), type “e” protection “Increased safety” is by no means sufficient by
itself! Two independent protection types and/or zone separation are required here.

The thermometer may only be connected to evaluation equipment that complies with the conditions
mentioned above.

5.5 Use in areas with an explosion hazard caused by dust

Dust explosion protection: safe limitation of energy

Type of protection “protection type intrinsic safety”

For the safe limitation of the energy fed to the sensing element – also in the event of a fault of the supply unit
– using a circuit with “intrinsic safety” protection is highly appropriate. The protection type “protection type
intrinsic safety” means that, in the area with an explosion hazard caused by dust, the only criterion is the
characteristic of safe limitation of electrical variables in the intrinsically safe equipment by means of the
associated intrinsically safe devices.

Head-mounted transmitters in Category 1G or 2G are included in the “Protection through enclosure” type of
protection within the terminal head. The associated intrinsically safe device, which has to be positioned
outside the hazardous area, need not meet the requirements of Category 1D or 2D. The category marking
for equipment requirements in areas with an explosion hazard caused by gas 1G or 2G are therefore
sufficient for the intrinsically safe equipment or the associated intrinsically safe devices.

Associated electrical manufacturing equipment outside
of the Ex-area

For approval "D"

Must have "D"!

For approval "G"

Must have "G"!

For approval "ia"

Must have "ia"!

Table 3: Electrical manufacturing equipment in the / outside of the Ex-area