Pressurized devices can also be filled by means of a pressure pump
with a pressure pump” on page 74.
A temperature set point Tset of more than 90 °C can only be
entered when the pressure overlay is activated.
1.
Connect the compressed air hose to the compressed air connection
of the constant temperature equipment.
2.
Switch on the constant temperature equipment.
3.
Press the [Enter key] to open the software menu.
Select the menu items
Pressure overlay
Set pressure
.
An entry window opens. The values displayed for
Max: 4.0
and
Min: 0.0
specify the limits for the value entry.
4.
Enter the value and press the Enter key to confirm.
The constant temperature equipment starts the pressure overlay
directly after the input. The supply of compressed air is automati-
cally stopped after the entered pressure has been reached.
If the application loses the heat transfer liquid or it is drained, the
pressure overlay is switched off when the low level is reached and
the gage pressure in the expansion vessel is released.
If the entered gage pressure cannot be reached, the device
indicates a warning or the device will go into the Fault state,
depending on whether the current temperature of the heat
transfer liquid is below or above the boiling temperature at atmos-
pheric pressure
5.
The Integral thermostats with pressure overlay have a built-in safety
valve which limits the pressure in the expansion vessel to a maximum
of 4.5 bar. This safety valve is not intended for pressure compensation
during regular operation. In the event of a fault, this safety valve
prevents a further increase in pressure in the expansion vessel but not
in the application!
6.
Only switch off the constant temperature equipment when the heat
transfer liquid has a moderate temperature (room temperature).
7.
Select the menu items
Pressure overlay
Set pressure
.
The Input window opens.
8.
Enter the value 0 for Pset and press the Enter key to confirm.
The pressure overlay has been switched off.
Ambient pressure is reinstated in the pressure vessel of the
device.
Activating and deactivating the pressure
overlay
Activating
Operation
Deactivating
V6
Integral Process Thermostats and High-Temperature Thermostats
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