We were approached to provide a control solution for remote latching solenoids over a distance of 1200m.
Latching solenoids are commonly used in the irrigation market as they are very low power.
Latching solenoids require a special driver circuit which controls the polarity of the switching signals.
This previous post details a simple on off remote control for a latching solenoid.
However, this enquiry needed a system to interface to the existing irrigation controller.
The irrigation controller’s output was already for a latching solenoid – so how do we transmit that over more than a kilometre?
A novel system was prescribed to convert the latching output to a relay closure, then transmit the relay status, and then convert it to latching at the solenoid end.
The solution used both the QTech LSD01 and the IPC relay module, usually used for solid set irrigation projects.
The WP2P systems’ relay outputs are momentary operation from the connected input switches. However they also have a “fail safe” option allowing you to select what happens if the communication link goes down.
If you need control for remote latching solenoids or remote control of valves – with or without latching relays – please contact us for assistance.
For those interested, “H” bridge circuits are usually used for solenoid polarity switching.