I want to put a Z-Wave controller on a remote irrigation valve. I can get latching solenoid controllers for the valve that can switch on or off using as low as 9Vdc. What I need is a battery powered Z-Wave device that can trigger the solenoid (close the 9vdc circuit, momentary contact). There is no "shore power" available where the irrigation valve is and it currently is operated with a self contained battery powered timer (no remote access or monitoring).
I've seen some older devices that are no longer available, looking to crowdsource the collective knowledge of the community to potentially find something available today that my searching has overlooked.
One battery operated Z-Wave device that can perform an output action is the Ecolink SDLS2-ZWAVE5 light switch.
It has a battery operated motor that moves a lever, see pic below.
Might work for you with some mods.
I assume that your current battery is 12 Vdc. You could use a 12 volt to 5 volt (ie USB) adapter to power a Zen17 relay. This will provide the contact closure you need, and also provide a means of sending the current valve status remotely.
A Google search, which I assume is factual, suggests that Battery powered devices don't listen for commands constantly, so such a relay device would not be responsive. Locks are the one exception.
That limitation works fine for a battery operated contact sensor, because it will remain sleeping until a door opens, and then wakes up to transmit the change. That wouldn't work for a relay.
I'm looking at the Zen17, but the one catch is that you can't use the USB-C power input (see the manual's discussion of "impulse power"). It would have to be batteries (lithium or off-the-self energizers in a series array) with direct power feed to the +/- screw terminals. The Zen17 does not reliably draw enough power to keep a USB power pack ("battery") turned on.
Still not a huge deal, maybe power it with a couple 9v in series (the Zen17 requires 12-24v power for itself). Use a separate 9v for powering the solenoid on dry contact closure.
Also I will need to package everything up in a water tight box small enough to shove into the irrigation control box. The Zen17 is not environment resistant.
I couldn't find any reference to "impulse" power in the Zen17 manual. More than likely what you read was related to using USB-C chargers which communicate with the device (ie phone) to adjust the output power. These chargers would not work with the Zen17. You would need to use a standard USB-A charger.
But that is all irrelevant since the Zen17 can accept a direct 12v input. Thanks @velvetfoot
The specs for the Zen17 say that it consumes 1 watt. If you used 2 9v batteries in series (18 volts} , the Zen17 would consume .05 amps. Since 9v alkaline batteries have a rating of 1AH, your batteries would last 20 hours. You can see now why they don't make battery operated devices that need to be awake 7/24.
So obviously you can't run this on "flashlight" batteries. You will need to use a 12 volt battery. You could continue to use 9v to operate the solenoid, but that would likely be safe to operate at 12v as well.
If you used a small 12 V battery, (similar to those used in an alarm panel) with a capacity of 5 AH, the Zen17 would consume .08 amps, and the battery would last 62 hours. If you used a large RV style battery, rated at 100AH, it would last 1250 hours.
If you could use a solar charger, to provide power for the Zen and to recharge the battery during the daytime, the smaller battery may last indefinitely.
It wouldn't take much effort to run a pair of wires to a sheltered area. Just push a shovel into the soil, pull it to one side, drop the wire into the gap, and then stomp it down again.
There is no shelter nearby that would keep the Zen17 dry, and at that point I start digging, I'll just trench a wire from the valve controller to an actual irrigation control system (probably with WiFi support) mounted next to a power source.
I'm not against it, but I currently have no ZigBee devices in my setup. However if there is a out-of-the-box ready to plug-in solution, I'm all for it.
The adapter plug looks like my phone charger cube, could I use that instead?
NO. Your charger cube is an impulse power supply, while the adapter linked above is an external battery, which supplies constant, steady power.
The difference between chargers and adapters is impulse power supplies require a load to activate, so a particular amount of charge on the other side. Laptops, tablets, and phones have powerful batteries that will start drawing a certain amount of power which activates the power supply. If a given device doesn't draw enough power, the power supply / charger will not activate.
I think that is referring to the new PD USB chargers (ie Power Delivery). These are identifiable by their USB C port.
They sense when they are connected to a device with a battery (phone, laptop, etc), and the device will control the output for optimum charging of it's own battery, without overheating it. The older adapters, with USB A ports, put out a fixed voltage and are often used to provide power to devices like the Wyze Cameras, and Hubitat Hubs.
Of course this is all FYI because it would be inneficient to convert 12v to 5v, when the device could work directly from 12v.
