8.3 The system pressure in devices with pressure overlay
The system pressure in the hydraulic circuit from the constant temperature
equipment to the application is composed of the static pressure, which
is influenced by the pressure overlay, and the dynamic pressure, which is
generated by the pump.
Fig. 80: Graph of system pressure
System pressures of up to 11 bar can occur owing to the maximum pressure
overlay of 4.5 bar and the maximum pump pressure of 6.2bar bar.
8.4 Setting the parameters for a pressure-stable application up to the maximum system pressure
If the application is stable against the heat transfer liquid pressure of up to
11 bar, select the following settings for the parameters:
Tmax
- 145 °C (water-glycol mixture)
Tmax_return
- 165 °C
Tih
- This is the highest temperature permissible for the
Set pressure (Pset) - 4.0 bar
The set pressure (Pset) is stated as a relative pressure in relation to
the ambient pressure. A Pset = 4 bar is therefore equivalent to an
absolute pressure of around 5 bar at sea level.
8.5 Setting the parameters for a pressure-stable application
WARNING!
Escape of steam or fluid
Scalding
Tmax, Tmax_return, Tih and the pressure overlay Pset must
be set according to the specifications in the operating
manual.
Fig. 79: Formula for system pressure
V6
Integral Process Thermostats and High-Temperature Thermostats
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