Solar panels are becoming ever more commonplace but the regulators can be pricey items indeed. You do need a regulator otherwise there is a real risk that a permanently connected solar panel will overcharge your battery and cause it to boil dry.

This low cost regulator is especially attractive since it has the bonus of the LCD panel to show the voltage or current. There will no longer be any need to dig out your trusty multimet-er to check the state of the battery – it is on display all the time.

Whether you have a large or small solar panel, you will need a solar panel regulator to avoid overcharging your battery. This design works at 12V or 24V and includes an LCD to show voltage or current. The solar panel is from BP Solar – Model BP 280F, 80W, $795 rrp. Phone (02) 9454 5111.

There are two switches associated with the regulator. The slide switch selects 24V or 12V operation and will only need to be set when the unit is initially connected up. The toggle switch is used to select voltage or current readings on the LCD panel. It will read current up to 5A and voltage up to 30V.

There is a 4-way insulated terminal block for the connec-tions to the battery and solar panel and all connections can be permanent, since the regulator’s operation is automatic.

A relay disconnects the solar panel when the battery reaches full charge and a LED comes on to indicate this condition. A series diode prevents the battery from discharging via the panel when the sun goes down.