
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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Example UB 20 J:
Setting screw
Operating chamber
Laboratory thermostats operate with liquids (operating medium, heat transfer oil) which
serve for energy transfer to the product to be thermostated.
The thermostated products can be immersed in the thermostatic bath (bath thermostat),
or placed in an external open bath circulated by the pump of the thermostat.
When operating as a circulator the thermostatic liquid is pumped through an external
heat exchanger arranged by the user in which a product is being thermostated (jacketed
vessels, reactors, heat exchangers).
3.2 Materials
All materials in contact with the bath liquid are made from rust-free stainless steel or
materials of similar anti-corrosion properties.
3.3 Cooling
coil
All units are fitted with a cooling coil which permits cooling, e.g. with water, for working
temperatures in the range of the ambient temperature (see Item 4.4.5 and Section 8).
3.4 Pumps
The units are fitted either with a pressure pump (type designation without -D) which we
call SIMPLEX pump or with a pressure/suction pump with automatic level control (type
designation with -D) called DUPLEX pump. Both types are submersible centrifugal
pumps.
SIMPLEX pumps have a single pressure stage; they are used for thermostating closed
external systems or when the unit is used mainly as a bath thermostat.
DUPLEX pumps have a pressure stage and a suction stage. The output of the pressure
stage is adjusted by a float in accordance with the bath level so that the two stages have
the same output. This enables to thermostate external open baths. The pumps are
driven by nonsynchronous outside rotor motors with overload protection embedded in
the motor winding.