Pressures And Differential Pressures In The Cooling Circuit - Siemens SIMOTICS FD 1LH1 Operating Instructions & Installation Instructions

Preparations for use
4.4 Configuration of the cooling circuit and coolant supply
Use either stainless steel or steel (S235JR) for the cooling circuit pipes and fittings.
4.4.2

Pressures and differential pressures in the cooling circuit

The maximum permissible overpressure in the heat sink and thus in the cooling circuit must not
exceed 6 bar.
● If you are using a pump, which reaches more than this maximum pressure, then on the plant
● The lowest possible differential pressure between the coolant in the supply and return lines
● The pressure drop is dependent on the machine type. The machine type is stamped on the
● If there is a risk of frost, use cooling water with antifreeze suitable for this temperature.
See also
Connecting the cooling water supply (Page 70)
30
or system side ensure that the maximum pressure is not exceeded.
should be selected to allow use of pumps with a flat characteristic. The maximum differential
pressure for a heat sink varies from shaft height to shaft height. Higher pressure differences
significantly increase the risk of cavitation and abrasion.
Machine type
1LH....-3A...-....
1MH....-3A...-....
1LH....-3B...-....
1MH....-3B...-....
1LH....-4A...-....
1MH....-4A...-....
1LH....-4B.1.-....
1MH....-4B.1.-....
1LH....-4B.3.-....
1MH....-4B.3.-....
1LH....-4B.5.-....
1MH....-4B.5.-....
1LH....-4B.7.-....
1MH....-4B.7.-....
rating plate.
The pressure drop increases when antifreeze is added.
Flow rate ± 10 %
[l/min]
40
40
60
60
60
80
80
Pressure drop for fresh water
[bar]
1.0
1.2
1.1
1.2
1.2
1.2
1.2
SIMOTICS FD 1LH1
Operating Instructions 01/2019