7 atex – JUMO 14597 safetyM STB/STW Ex - Safety Temperature Limiter and Safety Temperature Monitor Operating Manual User Manual
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"The automatic safety devices shall only be capable of being reset by the use of a tool or a key."
The requirements of EN 60079-2 are met for the relevant ignition protection.
Definition from EN 60079-2 for type py:
Pressurized enclosure that reduces the equipment protection level (EPL) within the pressurized case from Gb to Gc.
Definition from EN 60079-2 for type pz:
Pressurized enclosure that reduces the equipment protection level (EPL) within the pressurized case from Gc to "non-hazard-
ous".
Dust markings "p Dc" and "p Db" are made on the basis of EN 60079-0:2009.
The requirements of EN 60079-2 for "py" and "pz" are equivalent to ignition protection "pD" in EN 61142-4:2006 (static pres-
surized enclosure for potentially explosive dust atmospheres).
The allocation for gas and dust atmospheres is as follows:
7.5.2.3
Application as safety device for static pressurized enclosure
The safety features for use of pressure 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 accordingly for
the pressure transmitter. The requirements from Table 1 of EN 50495 apply. The signal is fed in via the 4 to 20 mA input. The
pressure signal can be displayed by parameterizing the current signal.
v
See Chapter 10.5
The alarm relay output in Chapter 4.3 "Connection diagram",
no. 10 in the key, is then used according to EN 60079-2 to imple-
ment the protective measures determined by the user if the overpressure falls below the minimum value specified by the user.
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 pressure gradient of the monitored pressure system
including the JUMO safetyM STB/STW and the pressure transmitter are taken into account.
Dust
Gas
"p Dc"
"pz"
"p Db"
"py"