
LAUDA Ultra-Thermostats
UB 20(-D), UB 25, UB 50, UB 30, UB 40
UB 20 F, UB 20 J, UB 30 J, UB 40 J, UB 65 J
UB 20 JL, UB 30 JL, UB 40 JL
YATE0013 /10.04.02
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In both fault conditions the display indicates the corresponding message and additionally
an audible signal draws attention to the fault. The switch-off function of the safety circuit
remains stored even during a break in the supply or after having switched off the supply.
Reset is possible by pressing the reset key
, but only after having eliminated the
troubles.
The pump motor is fitted with a temperature monitor which switches off if the motor
winding overheats. The heater is also switched off simultaneously. After the motor
winding has cooled down the pump starts up automatically.
4.2
Why can a thermostat be dangerous?
1.
Thermostats are equipped with heaters supplying the necessary heat to the
thermostating liquid. If the temperature control fails or if the liquid level is too low,
the heater may reach temperatures which can lead to a fire in the laboratory,
especially in combination with flammable liquids.
2.
When using the thermostat as a circulation thermostat a hose may break,
causing hot liquid to spill and endangering people and goods.
The safety requirements on thermostats therefore depend on whether
o
non-flammable or flammable liquids are used
o
operation is with or without supervision
The thermostats described in these Operating Instructions are protected against
overtemperature and low liquid level (FL) when operated according to the regulations.
The units can be operated with non-flammable bath liquids and with flammable bath
liquids up to 25°C below their fire point (EN 61010) on condition that there is a correct
adjustment and regular testing (see Item 9.13) of overtemperature and low-level
protection.
4.3 Important
notes
The user is only protected against those hazards which are caused by exceeding the
temperature and by low liquid level.
Further hazards may arise from the type of product being thermostated, e.g. a shift
above or below certain temperature levels or a fracture of the container and a reaction
with the thermostatic liquid, etc.
It is impossible to cover all possible causes, and they remain largely within the decision
and responsibility of the user.
Values for temperature variation and indication accuracy apply under normal conditions
according to DIN 58966. In special cases high-frequency electromagnetic fields may
lead to less favourable values. There is no loss of safety.