Thermo Scientific HAAKE RotoVisco 1 Instruction Manual page 64

Temperature Control Units
Peltier modules transport heat from one side of the module
to the other and thus can be understood as the thermoelec-
tric system of a solid state heat pump. Heat itself is scarcely
absorbed during this process. The heat side is in any case
exposed to the dissipated energy in addition to the trans-
ported Peltier heat which has the result of causing the heat-
ing and cooling measuring curves not to be identical. The
maximum heating rate is therefore higher than the maximum
cooling rate.
Operation
In the temperature control unit a cooling coil (with hose con-
nections for liquid cooling) is built in to cool the Peltier ele-
ment.
!
The connector nozzles of the heat exchanger may
not be closed during operation. A high overpres-
sure may exist during the heating up.
The temperature control plate is set in a plastic part (TEKA-
PEEK).
!
Recommended couling liquids are water or
mixtures of water / alcohol as well as water / glycol.
!
The maximum for the temperature of the couling
liquid is 100 C.
Cooling and Heating
Since the Peltier temperature control unit is cooled by circu-
lating water the temperatures as well as the heating and
cooling rates (times to reach those temperatures) depend on
the temperature and of the flow through rate of the coolant.
By variation of the flow-through temperature and the flow-
through volume optimum conditions can be reached for
every working range desired.
In general, the following applies:
 During heating the temperature control unit will reach
a max. temperature difference of abt. 100C between
temperature control plate and the temperature of the
coolant under optimum conditions.
 During cooling the temperature control unit will reach
a max. temperature difference of abt. 20--40C
between temperature control plate and the tempera-
ture of the coolant under optimum conditions.
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