For a battery-powered field device, the biggest enemy is wasted energy. The ESTRON controller uses power carefully: installed once, it runs for years without a power line or frequent battery changes. If the price of going wireless is a battery, keeping that price small is the job of the design.
Wired cabinet or battery controller?
| Wired control cabinet | Battery controller | |
|---|---|---|
| Power | Mains electricity, transformer | 2 × 9 V batteries, in the valve box |
| Link to the valve | Cable from the cabinet to every valve; trenching | Controller beside the valve; no cable |
| Site without power | No cabinet possible | Works |
| Power cut | Cabinet stops; backup battery needed | Unaffected |
| Remote control | Communication added to the cabinet | Built in: Bluetooth + LoRaWAN |
| Maintenance | Cable faults, cabinet upkeep | Battery change, years apart |
| Expansion | Cabinet capacity and cabling | One controller per valve |
The battery replaces the cable. Every metre of cable not laid is trenching and maintenance avoided. On scattered sites this difference makes a wireless central system possible.
The device sleeps most of the time
ESTRON devices spend nearly all of their time in "sleep" mode, where they use almost no energy. The device only wakes for a few seconds when it is time to send data: it takes the measurement, does what is needed, transmits the data and immediately goes back to sleep. This simple discipline is the single most important factor that stretches battery life into years.
What sets battery life?
- Reporting interval. The biggest factor. Every transmission is a wake-up. See the table below.
- Valve operations. Each open and close is a short pulse to the coil. A few runs a day do not change battery life noticeably.
- Link quality. A device far from the gateway or behind obstacles transmits at higher power and with more retries. Gateway placement affects battery life too. See how far does LoRaWAN reach?
- Sensor readings. The number of connected sensors and the reading interval add a small share.
- Battery quality. Fresh batteries with a long shelf life are used; the battery stays dry in the box.
The more often data is sent, the faster the battery drains
The reporting interval is set to match the need; battery life stretches accordingly:
| Reporting | Battery life |
|---|---|
| 1 message per day | Several years |
| 1 message per hour | Roughly 1–2 years |
| 1 message every 5 minutes | A few months; for situations that need close monitoring |
Valve commands are independent of this interval: a command sent from the panel is picked up at the next wake-up. When the internet is down the controller keeps running the schedule from memory: irrigation keeps running even without internet.
It warns you before the battery runs out
ESTRON devices continuously measure the remaining battery level. As the battery approaches a critical level, they send an alert weeks before it runs out, so you can replace the battery in a planned way without facing an unexpected outage.
Mounting in the valve box
- The controller is fitted in the valve box, next to the solenoid. Water must not collect in the box.
- The solenoid wires connect to the controller's two outputs. Two valves in the same box share one controller.
- The batteries go in; the cover is closed.
- The mobile app connects over Bluetooth; line name, schedule and reporting interval are entered.
No digging, no cable trench, no power connection. Mounting details: mounting; product page: LoRaWAN battery valve controller.
Changing the battery
The panel warns when the battery runs low. On site the cover is opened and the two batteries are replaced; it takes minutes. The schedule stays in the controller's memory; no reload is needed. At winter shutdown, batteries that read low are replaced without waiting for spring. Season calendar: how to winterize an irrigation system.
Frequently asked
Does watering stop when the battery dies?
A warning comes weeks before the battery reaches a critical level. A battery replaced after the warning causes no interruption.
Which battery is used?
A standard 9 V battery, two of them. Available anywhere; no special battery needed.
Does the gateway have a battery too?
No. The gateway runs on mains power, PoE or a solar panel; it is the one power point on site. Other questions are on the FAQ page.