Lauda UWT Series, Руководство по эксплуатации

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UWT circulation heat exchangers
YAWE0029 / 29 June 2018
Unit description
9
3 Unit description
3.1 Environmental conditions
The operation of the thermostats is only allowed under the following conditions as specified in
EN 61010-2-010:2003 and EN 61010-1:2001:

Indoor use.

Altitude up to 2000 m above sea level.

Foundation must be dense, even, non-slippery and non-flammable.

Ambient temperature range (

8.1).
Use only within this range for an undisturbed operation.

Mains supply voltage fluctuations (

8.1).

Maximum relative humidity 80 % for temperatures up to 31 °C, decreasing linearly to 50 % relative
humidity at 40 °C.

Transient over voltage according to Installation Categories (Over voltage Categories) II.

Pollution degree: 2.
3.2 Unit types
The type designation of the circulation heat exchangers in the Series UWT is composed of the prefix
designation UWT and the nominal transfer power of the heat exchanger.
Example: The UWT 6000 has a nominal transfer power of 6000 watts.
3.3 Principle of operation
The circulation heat exchanger dissipates heat from a laboratory circuit (secondary circuit) into an ex-
ternal cooling circuit (primary circuit).
To achieve this, the circulation heat exchanger is connected to a supply of cooling liquid available at the
customer's premises (maximum pressure

8.1). In the circulation heat exchanger the cooling liquid is
passed through the primary side of a plate-heat exchanger. Its secondary side is connected to the cir-
cuit of the circulation heat exchanger. It consists of an open bath vessel and a pressure pump. When
required, a temperature controller opens a solenoid shut-off valve in the primary circuit and dissipates
heat through the heat exchanger until the selected set-point temperature is reached.
3.4 Pump
The circulation heat exchanger has an integral pressure pump which provides the transport of the heat
transfer liquid in the secondary circuit.