# Elettrovalvola irrigazazione

Ciao, ho una elettrovalvola da 24V per l'irrigazione. Se la alimento con 20V al posto di 24V funziona? Inoltre quando la collego al trasformatore 220-24V, si crea un cortocircuito, qualcuno sa il perchè? GRAZIE

Ross95: Hello, I have a 24V solenoid valve for irrigation. If supplied with 20V instead of 24V does it work? Also, when I connect it to the transformer 220-24V, it creates a short circuit, does anyone know why?

Hi and welcome. Please speak English in the international part of this forum.

Your valve will probably work at 20 volts, because the voltage isn't that critical. As things go with electronics, the power is what is important. And power is the product of voltage and current. If you lower the voltage (of course within limits), there will be need for some more current in order to get the same power.

A valve normally is controlled by a coil. That has a relative low resistance (a 24 volt coil with a resistance of just over 15 Ohms so drawing about 1.5 A is quite normal), and a short is a very low resistance. You need to know some of the characteristics of that valve/coil in order to do the math on it. If you know the power and a voltage the coil is rated at, you can find out what current you need to supply. And of course if the current is specified (in Amperes) you'll know that too. See if the power and / or current can be supplied by your power supply at all.

A coil also briefly draws more than the nominal current when switched on. So if your power supply is just strong enough to power the coil, it might shut down due to over current when switching the coil on.

Thaks My valve is 24V and my transformer is 220-20V 5VA Are they ok to work together?

5 VoltAmpere or 5 Watts means (5VA / 24 V=) 0.21 Ampere.
That is not nearly enough to supply power to any valve i know of.
This is also the reason you see a short when trying to use this supply with your valve.

If you have a multimeter, measure the resistance of your valve.
That will give you an idea to what current you need, but make sure you can supply some more than that.

Totally spurious comment: I love the phrase "elettrovalvola irrigazazione", sounds much nicer than the English "irrigation solenoid valve" ;)

Thanks!