The temperature of the hydraulic fluid in hydraulic systems can be measured either with simple measurement devices (thermometer) or with a measuring device that issues signals to the control unit.
The simplest method is measuring the temperature of the pressure fluid in the tank. However, this method constitutes a rough estimate and does not allow conclusions to be drawn regarding the temperature of the pressure fluid at certain locations within the system. For example, the temperature of the pressure fluid may be very high at certain throttle points. If the temperature of the pressure fluid must be known at certain points within the hydraulic system, pressure-resistant sensors must also be fitted at these locations.
The temperature measurement is particularly important as high temperatures (> 60°) lead to premature ageing of the hydraulic fluid and seals. Large differences in temperature also result in large differences in the viscosity of the medium.
To keep the temperature constant, thermo switches or thermostats are used, which switch on the cooling or heating system when necessary.