JUMO 14597 safetyM STB/STW Ex - Safety Temperature Limiter and Safety Temperature Monitor Operating Manual - Manual (Page 86)

7 ATEX
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ous state can occur when all relevant factors such as response time and, if applicable, temperature overshoot of the monitored
apparatus including the JUMO safetyM STB/STW 70155 are taken into account.
To prevent unintended changes to the set parameters, the JUMO safetyM STB/STW must be sealed according to Chapter 5.8
of this Operating Manual or a keypad lock or level inhibit must be used according to Chapter 8.4.
7.5.1.4 Application of temperature transmitters
The safety features for use of temperature transmitters are described according to variant 5 in Table 1: "Achievable SIL" in
Chapter 6.6 "Connection possibilities of the sensors (SIL)". The required features based on EN 50495 must be identified ac-
cordingly for the temperature transmitter. The requirements from Table 1 of EN 50495 apply. The signal is fed in via the 4 to
20 mA input. Setting is according to Item 8.2.2 onwards.
The limit value must be determined according to the relevant use and/or application. The value must be set so that no danger-
ous state can occur when all relevant factors such as response time and, if applicable, temperature overshoot of the monitored
apparatus including the JUMO safetyM STB/STW 70155 and temperature transmitter are taken into account.
To prevent unintended changes to the set parameters, the JUMO safetyM STB/STW must be sealed according to Chapter 5.8
of this Operating Manual or a keypad lock or level inhibit must be used according to Chapter 8.4.
7.5.2 Minimum overpressure monitoring for static pressurized enclosure on the basis of ignition
protection "p", pressurized enclosure according to EN 60079-2
7.5.2.1 Function of the static pressurized enclosure
Ignition protection in which the formation of a potentially explosive atmosphere inside a case is prevented by an inert protective
gas that maintains an internal overpressure greater than the external atmosphere. This ignition protection prevents the ignition
source from coming into contact with the potentially explosive atmosphere.
7.5.2.2 Safety device for static pressurized enclosure
Fulfillment of the requirements of EN 60079-2 for the JUMO safetyM STB/STW as a safety device for static pressurized enclo-
sure for ignition protection type "py" or "pz" (gas atmospheres) or "p Db" and "p Dc" (dust atmospheres) (each with a corre-
sponding number of sensors) has been verified by TÜV NORD CERT GmbH. Application for static pressurized enclosure is only
admissible in the function as "STB", as EN 60079-2, Section 8.5 on safety devices (for static pressurized enclosure) stipulates: