2
IC.PS.600.A4.02 / 520B2809
IC.PS.600.A4.02 / 520B2809
How to Choose
It is important to indentify all relevant parameters when selecting a solenoid
valve.
This includes:
• Capacity / k
v
- value
• Pressure conditions
• Media conditions
• Other conditions
Pressure conditions:
Open system (system with drain)
In an open system the pressure conditions are well-defined.
This enables clarification as to whether there is sufficient pressure differential to
be able to open a servo-operated valve. The following types of valves are
well-suited for use in open systems:
EV210B, EV210A, EV310B and EV310A direct -operated solenoid valves
EV220B, EV220A and EV225B servo-operated solenoid valves
Capacity / k
v
- value:
– Specifies how many
m
/hour
(capacity) water is passing through the valve at a
differential pressure at
bar.
– Is a result of all the different constants coming from shape of orifices, units etc.
which are reduced to one new constant, the k
v
- value.
– Is used to calculate capacity:
–
ρ =
density (kg / m
3
)
– ΔP = P
1
- P
2
Q = k
√
∆P [m3 / h]
V
ρ
Closed circuit (cirulating system)
In a closed circuit system the pressure conditions are undefined. Therefor a
solenoid valve capable of opening without pressure differential is required.
EV250B assisted lift servo-operated valve
EV210B, EV210A, EV310B and EV310A direct-operated solenoid valves