** Instructions for the new cloud function can be found here **

General Questions

What is OpenSprinkler?

OpenSprinkler is an open-source, web-based sprinkler/irrigation controller. It is a drop-in replacement for traditional sprinkler controllers that are not web connected. A web connected controller like OpenSprinkler offers the following advantages:

  • Intuitive user interface (UI) : no more messing with buttons and knobs, no more running to your garage to make a single sprinkler program change. Instead, use the web browser and mobile applications to set or change sprinkler programs. The web interface is much more intuitive than a small LCD screen.
  • Remote Access : You can your OpenSprinkler anywhere, anytime whether you are at home, in the office or traveling away (configuration required)
  • Smart Control : OpenSprinkler can connect to the Internet and use real-time weather data (including historical and forecast data) to automatically make water time adjustments. Not only does it stop watering when it rains, it also scales the water amount and time up and down based on your local outside temperature and humidity.
  • Connection options: we offer both controllers with built-in WiFi and controllers with built-in Ethernet port. In addition, the WiFi version can work without an external router, ideal for situations where you do not have an internet connection in the field.
For whom is OpenSprinkler suitable?

OpenSprinkler is suitable for homeowners as well as businesses, churches, farms, business parks and greenhouses. Typical applications include lawn and garden irrigation, plant irrigation, drip irrigation and hydroponics. It is inexpensive and expandable: OpenSprinkler can scale from 1-2 zones for a home to 72 zones for a large enterprise. With our app you can access several OpenSprinklers access.

Also often used for

  • Lawn and plant watering system for hotels and hotel complexes
  • Soccer, tennis and sports fields (field irrigation), e.g. for sports clubs
  • DIY stores with a horticultural market for the exhibition plants
  • Golf courses

Solenoid valves (e.g. 24VAC from Hunter, Rainbird and many more) are required for the connection to the water lines.

How many zones are supported?

By default, 8 zones are supported on the main controller. Each expander adds 16 zones. The latest firmware (2.1.9) supports a maximum of 72 zones.

What are the differences between the different hardware versions?

We are currently offering OpenSprinkler 3.2 (with built-in WiFi), optional with Ethernet port and OpenSprinkler Pi (or OSPI, powered by a Raspberry Pi). In addition, there is the OpenSprinkler 3.2 in three different variants: AC powered, DC powered, and Latch. AC-power and DC-power versions both work with standard 24VAC sprinkler valves. The main difference is that the AC version is powered by a 24V AC power supply and the DC version is powered by a low voltage 7,5V DC adapter. For international customers: DC adapters are usually much easier to find than AC adapters. In addition, DC power version can work with any input voltage from 5VDC to 12VDC, including 12VDC solar panel. The latch control is also powered by a DC adapter but will only work with latching solenoids.

How many programs are supported?

The latest firmware (2.1.9) supports up to 35 programs OpenSprinkler 3.0 and OSPI. Each program allows an individual watering time for each station (from 0 to 18 hours, to the second) and two different schedule types:
1) Weekly schedule where you can choose any combination of weekday (e.g. Monday and Wednesday);
2) Interval schedule where you can run the program every n days (n between 2 to 127) (e.g. every 3rd day).

Each program also allows two types of start times:
1) up to 4 fixed start times; or
2) Repeat start times (e.g. start at 8:30 am, repeat every 45 minutes for 8 times).

The flexible start times can be combined for both cases, so you can schedule watering many times a day with recurring intervals.

How differs OpenSprinkler from competitors?

Web based sprinkler controller is not a new idea. OpenSprinkler differs from similar products on the market in the following aspects:

  • OpenSprinkler it has a built-in web interface and runs programs on its own processor. It does not rely on proprietary or PC-only software or cloud-only software. The web interface works with any modern browser. The HTTP API is well documented and allows local access without a cloud server. Our mobile app is free and supports all major platforms.
  • You can easily expand the number of zones up to 72. The cost is significantly cheaper than competing products on the market.
  • The software provides an advanced set of features such as support for two independent master zones; Support for rain sensor, flow sensor, program start switch; manual control using buttons, special station such as remote, radio frequency (RF), GPIO and HTTP stations. It offers flexible program start times, graphical preview of program schedules and log data, user-defined zone and program names, supports either sequential or parallel zones, watering time can be run to within 1 second. These features are rarely found in competing products.
  • We offer both the WiFi option and Ethernet jack option. In addition, we don't rely on cloud connections, so your controller works even when the internet is offline. The WiFi option also works in AP mode without an external router.
  • OpenSprinkler is shipped worldwide and supports more than 20 different languages.
  • OpenSprinkler based on open source hardware and software. His design files are publicly available. If you are a technical developer, you can easily customize and extend its functionality in both software and hardware.
Where can I find the open source files?

All OpenSprinkler Design files, schematic, board design, firmware code, app code including circuit can be on the OpenSprinkler Find Github – Repository page: https://github.com/opensprinkler .

Installation and Use

What's in the package?

The package contains one OpenSprinkler Controller (8 zones). You still need an appropriate power pack. With the AC version, the output voltage must be between 22V AC and 28V AC. The DC power version and latch version require a 7,5V DC (5-12V DC) power supply. The DC version comes with an international power supply.

Hat OpenSprinkler an integrated network interface or just wireless?
  • Opensprinkler 3.0 only has WiFi built in (based on Esp8266 microcontroller) but no built-in Ethernet jack.
  • OpenSprinkler 2.3 has built-in Ethernet jack but no built-in WiFi.
  • OpenSprinkler Pi is powered by a Raspberry Pi, and networking options depend on your RPi.
  • OpenSprinkler 3.2 has WiFi and optionally a network adapter (ENC28J60 10MBit)
  • OpenSprinkler 3.3 has WiFi and optionally a network adapter (W5500 100MBit)
What kind of cable should I use?

For laying in the garden, use a "telephone underground cable", eg "A-2YLY2 diameter 0,8mm". This is available from 4 to 20 cores.


Type USAWG 20AWG 18AWG 16
cable diameter0,8 mm1,0 mm1,3 mm
cable cross-section0,5 mm²0,8 mm²1,3 mm²
length max200m300m450m


Type USAWG 20AWG 18AWG 16
cable diameter0,8 mm1,0 mm1,3 mm
cable cross-section0,5 mm²1 mm²1,3 mm²
length max100m150m200m


cable cross-section1 mm²
length max30 meters !!!!!!!

Thicker cables allow longer line lengths. Applies to standard valves with approx. 300 mA inrush current as well

  1. for AC an AC power supply with >= 36VA power (at 24VAC max 1,5A)
  2. with DC and latch a DC power supply >= 20W (at 7,5V-12V, approx. 2,7A)

The cable of the solenoid valves must be connected to this cable in a watertight/waterproof manner, e.g "3M Scotchlok 314 "

What kind of solenoid valves can we work with?
  • AC powered OpenSprinkler (including OSPI) works with standard 24VAC sprinkler system valves. It is compatible with existing 24VAC systems including pump start relays, wireless sensors that require 24VAC power. 24VAC valves open when energized and close when de-energized.
  • DC powered OpenSprinkler Works with both 24V AC sprinkler system valves as well as 12 VDC (non-latching) valves. It comes with a 2A power adapter, enough for 4 valves. However, for certain 24VAC pump start relays and wireless sensors that require large amounts of 24VAC power, you may need to provide a separate 24VAC power supply. 24VAC or 12VDC valves open when energized and close when de-energized.
  • Latch OpenSprinkler works only with DC magnetic latch valves. These are self-locking valves that require an impulse for each change of state.
I'm new to using sprinkler systems. How can I OpenSprinkler install with existing solenoid valves?

OpenSprinkler is designed to be a drop-in replacement of your traditional sprinkler controllers. Whether you are installing a new system or replacing an existing controller, do-it-yourself (DIY) installation is easy and can be completed quickly:

  • Carefully label and remove wires from existing controller.
  • Replace your existing controllers with OpenSprinkler, then the wires on OpenSprinkler connect.
  • Schlieen Sie OpenSprinkler to the router (WiFi or wired Ethernet).
  • Check out our tutorial videos in the Support – Page – Section Installation or this is how it works!
  • The manual in German English French also explains the installation.

If you have an existing sprinkler system installation, the wires should already be pre-wired and labeled. If you are installing a new system: Typically, each solenoid valve has two wires. Connect one wire to the COM (Common) terminal, and the other wire to a single zone opening (1 through 8). For multiple valves, one wire from each valve is combined together and goes to the COM terminal; the other wire goes to a single zone port. If you are unsure, you should seek help from a landscaper, an electrician, or a hardware store.

Is the OpenSprinkler waterproof?

No, the controller is not waterproof and must not be used outdoors without protection. For outdoor installations you should use one waterproof housing use one that comes with a built-in power outlet and has enough space around a OpenSprinklerto accommodate a few expansion cards and WiFi adapters.

Which sensors supported OpenSprinkler?

OpenSprinkler currently has two sensor ports which the software can use for a rain sensor, a soil moisture sensor, a flow sensor or a program start button. Any rain sensor or soil moisture sensor that works either as an opener or as a closer is supported. By default, dry contact flow sensors (ie two-wire type) are supported, but some three-wire types (with external 5V supply) are also supported. In addition, water meters with pulse outputs. The program start button allows you to connect a switch/button to the sensor port and start a program by pressing the button. The firmware allows you to configure the sensor type and choose the sensor parameters.

Hat OpenSprinkler Support for a soil moisture sensor?

Yes, a digital soil moisture sensor is supported from firmware version 2.1.9. Digital means it can show the soil moisture as a yes/no signal. For the OpenSprinkler we have the A2D in the program, which maps an analog signal to digital. As a soil moisture sensor, we recommend the SMT-50 from our shop.

But be careful: soil moisture sensors only measure the moisture at one point on the soil. If this is partially shaded, then the soil moisture values ​​are completely different from fully irradiated locations. The same applies to different soil conditions. We therefore recommend using the instead of soil moisture sensors OpenSprinkler weather services and a rain sensor.

The additional product "Analog Sensor Board" is new, which has 8 analog inputs and thus allows the connection of up to 8 analog sensors, such as the SMT50.

Hat OpenSprinkler Support for master zone or pumping stations?

Yes. OpenSprinkler uses software defined master zone/pump station, and supports up to 2 independent master/pump zones. Any of the available ports can be configured as a master/pump zone.

Can I put two wires in the same Zone Port?

Yes. But remember that when you do this, the two zones will always open and close at the same time.

Can I run multiple zones at the same time?

Yes. OpenSprinkler Firmware allows each zone to operate in 'parallel' mode by turning off the 'sequential' flag. A parallel zone can be executed simultaneously with other zones.

Can I OpenSprinkler use to switch devices, not just solenoid valves?

Yes. OpenSprinkler Firmware has built-in support for GPIO (general purpose) IO stations, HTTP stations, and radio frequency (RF) transmitters. This makes it possible to directly switch a spare GPIO, send a generic HTTP GET command, or talk to RF remote sockets, which in turn switch on any powerline device, such as landscape lights, Christmas lights, pumps, heaters, fans. Details can be found in our Blog – Article . Besides, you can also use 24V AC relays to OpenSprinkler to switch other devices. Details can be found in this Blog – Article .

What is the LCD and buttons for?

OpenSprinkler has an integrated LCD screen that displays the current time, zone status and rain status. The buttons are used so that OpenSprinkler displays the IP address or performs a factory reset.

How do I check the IP address that OpenSprinkler been assigned?

Click the B1 button, and the IP address will be displayed on the LCD screen.

How do I manually program a program key?

Hold the B3 button until the start a program message. Then follow the instructions on the LCD screen.

What happens if there is a power loss?

OpenSprinkler saves all programs and settings in non-volatile memory. The data is retained even in the event of a power failure.

web connections

How do I pick up OpenSprinkler to?

OpenSprinkler has an integrated web interface that works with most desktop and mobile web browsers. Just open a browser and enter the controller's IP address in the address bar. We also offer a free OpenSprinkler mobile app OpenSprinkler mobile app, search for 'OpenSprinkler' in your app store. The mobile app can automatically scan the local network and get the IP of OpenSprinkler early in the

Unlike some other web based controls required OpenSprinkler NO cloud connection - your data stays local on the controller. You can access on-site without going over the internet.

can OpenSprinkler run offline without internet connection?

Yes. Once programmed, can OpenSprinkler be run offline without a network connection at all. The controller has an integrated real-time clock and battery for timekeeping. You can also manually start an existing or test program on the controller using the buttons.

Can I do it without a WiFi router? OpenSprinkler ?

With the latest firmware (2.1.8), OpenSprinkler 3.0, all functions are supported in AP mode - it can serve itself as a wireless LAN hotspot, allowing mobile phones and laptops to connect and access it OpenSprinkler can access.

How do I pick up OpenSprinkler from afar too?

You can OpenSprinkler Remote – access through the use of Port-Forwarding share, this is available with most routers. To do this, you need to go into your router configuration page and create an entry in the Port Forwarding or Sharing section, which goes to the OpenSprinkler IP – address and port points.

With a Fritz!Box you will find this under “Internet / Releases / Port Releases”. There you add a port free for the IP and the port from OpenSprinkler a. The next step is to activate the option “Internet access to the FRITZ!Box via HTTPS activated” under “Internet / Sharing / Fritz!box services” under “Internet access” or create a corresponding address under “Internet / Sharing / Dyndns”. At the address specified under “Internet address of your FRITZ!Box” is then also yours OpenSprinkler available.

Important note: With some UnityMedia connections, only one IPV6 address is assigned, the IPV4 address is shared by several connections. As a result, it is unfortunately not possible to activate port forwarding. However, it still works via WiFi.

Will push notifications support?

Supported starting from firmware 2.1.7 OpenSprinkler Push notifications via IFTTT, which can be configured to send notifications via SMS, email or app notifications. Please check this support article for more details.

If I have several OpenSprinklers have, can you talk to each other?

Our firmware supports remote controllers - a feature that one OpenSprinkler allows as a master controller to send functional commands to one or more remote controllers to open or close their valves. This is useful when you have a large property with separate groups of valves.

What is the maximum distance between controller and valves?

This depends on the gauge of wire (AWG) you use to connect the valves. Generally you can run up to 200m with 20 AWG wires, 300m with 18 AWG wires and 450m with 16 AWG wires. Thicker wires allow longer distances.

What is the maximum allowed distance between the main controller and the expansion board?

Again, this depends on the wire gauge (AWG) of the extension cord. The standard cable shipped with expansion cards is a 24 AWG 15-inch long cable. You can increase this length by using a custom cable with thicker wires.

Can I connect the sprinkler system solenoid valves to garden hoses?

Secure. You will likely need a suitable adapter, these can be found online or at hardware stores.

How do I update the firmware?

OpenSprinkler 3.0 supports firmware - Update Over-the-Air (OTA) via WiFi. OpenSprinkler 2.3 requires a USB cable and a computer firmware update. OpenSprinkler Pi supports network or script based firmware update. Check the Firmware Update Manual Instructions page.

How can I use a static IP address?

The recommended method is to assign the IP via your router.

Alternatively you can use the OpenSprinkler Turn off the DHCP option, then you can enter a static IP. Note that you must set the router IP correctly for all functions to work properly.

How do I reset the settings to factory defaults?

OpenSprinkler turn off, then turn on again. If that OpenSprinkler logo appears, immediately press and hold the first button B1 until the message 'Reset All' appears? If you're sure you want those, then press and hold the third button B3 until the controller has restarted. Opensprinkler is then back to the factory settings.

How does the weather-related adjustment of irrigation actually work?

Weather Adaptation first uses your location and queries it through OpenWeatherMap to get real-time weather data. It then calculates a value that is applied to all water station watering % times. The percentage is calculated based on the local temperature, humidity and precipitation (precipitation) and varies from 0% to 250%. The value is updated every hour. For example, low temperature, high humidity and/or significant rainfall will result in reduced or no irrigation, i.e. 0%. On the other hand, high temperatures and drought lead to an increase in the irrigation time. At very hot temperatures, this can go up to 200%.

How can I OpenSprinkler help support more languages?

In OpenSprinkler Localized Language is a crowd-sourced feature, so anyone can help. Go to the web interface -> sidebar -> about page and click on the link on the localization.

Can I embed my own app or can I use my own custom scripts that interface with OpenSprinkler accesses?

Absolutely. Please see the support page for API documentation.

Technical questions

What is the difference between the different versions of OpenSprinkler?

OpenSprinkler is a fully assembled commercial product that works out of the box. It comes with buttons and display.

OpenSprinkler pi (Ospi) is a Sprinkler - expansion board for RPi - it uses RPi as main processor. Expect users to have some experience with RPI software to set up. Please check the specific product websites for more details.

Opensprinkler 3.0 AC/DC/LatchOpenSprinkler pi (Ospi)
Compatibilityac / dc / OSPI Both 24VAC sprinkler magnets work. OSDC supported zusätzlich 12V non-latching DC valves. Latch version only supports DC pulse coils.
Power SupplyOS AC and OSPI requires 24 V AC power supply (not included as standard)
OS DC and latch are versatile: 5V~12VDC (e.g. 5V USB, 12V solar panel). A 7.5VDC adapter is included.
number of stations8 (expandable to 72)8 (expandable to 72)
weather integrationJaJa
logging supportJaJa
Processoresp8266Fits RPi 1 Model A+/B+ or RPi 0, 2 and 3
Assembly necessary?Fully assembledRequires plugging into RPi and software setup
LCDYes (O 2.3: 16 × 2 characters; O 3,0: 128 × 64 OLED)None
Ethernet connectionOS 3.0: no
OS 3.2: yes
Yes (except RPi 1 A+)
Built-in WiFiJaYes, if your RPi has WiFi (e.g. via USB)
firmwareUniform OS firmwareUniform OS firmware
firmware UpgradeOver the Air (OTA)via network
target audienceEachRPi enthusiasts
Package includesOS controller, terminal blocks,
with enclosure
Ospi Plug-on add-on board, with terminal blocks, with housing. RPi not included.
HousingYes, injection moldedYes, laser cut acrylic
Optional AddonsOS3AC: 24V AC adapter
Zone Expander +16 Zones
24V AC adapter
Zone Expander +16 Zones