Samson 5343, Монтаж и эксплуатация

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EB 5206 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
3.1 Single thermostat
The thermostat is equipped with a change -
over contact. When the thermostat is trig -
gered, the connection between connections 1
and 2 are interrupted and the connections 1
and 4 are connected (see the 'Installation'
section).
Safety temperature monitors (STM)
A snap-action switch in the STM is triggered
when the temperature at the temperature
sensor rises above the adjusted set point.
When the temperature falls below the set
point by approximately 8 K, the switch re
-
turns to its original position.
The changeover contact interrupts the con
-
nections 2 and 4 and connects the connec -
tions 1 and 2 when the temperature at the
temperature sensor falls below –20 °C. It au
-
tomatically returns to the original position as
soon as the temperature at the temperature
sensor rises above –20 °C again.
The STM is triggered when the capillary tube
breaks.
Temperature regulators (TR)
The snap-action switch is triggered when the
temperature at the temperature sensor rises
above the adjusted set point. When the tem
-
perature falls below the set point by approxi -
mately 4 K, the switch returns to its original
position.
Safety temperature limiters (STL)
The snap-action switch is triggered and
locked when the temperature at the tempera
-
ture sensor rises above the adjusted set
point. When the temperature falls below the
set point by approximately 10 %, the
snap-action switch can be unlocked manual
-
ly.
The changeover contact interrupts the con
-
nections 2 and 4 and connects the connec -
tions 1 and 4 when the temperature at the
temperature sensor falls below –20 °C. The
STL automatically unlocks as soon as the
temperature at the temperature sensor rises
above –20 °C again.
The snap-action operation is triggered and
remains in this position in the event of a sys
-
tem failure. It is not possible to unlock the
device in this case.
3.2 Double thermostat
Double thermostats are two thermostats that
work independently but share the same
housing. The principle of operation is the
same as that of the single thermostat. Each
thermostat has its own capillary tube.
The following combinations are possible:
− TR/STL
− TR/STM
− STM/STL