Power & Energy Sensors

• 1: Power Management
• 2: Smart Switch
• 3: Power Monitoring

1 - Power Management

Power management sensors read the system that keeps everything else running: your solar and battery setup. They’re sensors like any other in OGLAS — they measure something off the world and report it — but what they measure is power production, battery state, and load, and they make it available to your hubs, your dashboards, and your smart switches.

The first of these reads a Victron MPPT.

Victron MPPT

If your power comes from solar — most off-grid sites — the Victron power-management sensor pulls production data into the same dataset as everything else.

• Reads from a Victron MPPT — incoming watts, battery state, and load — without touching the Victron app or VRM cloud.
• Logs locally alongside every other sensor reading, so production and consumption sit in the same dataset — your data, your dashboards, no VRM subscription.
• Shares its data with other OGLAS devices — particularly Smart Switches — so they can react to it. “Battery above 80 %, watts above 600” becomes a trigger anywhere on the site, not just next to the MPPT.
• Shows it on screen — pair with a large display to see solar production, battery state, and load alongside your sensor readings.

Source, not actor

Earlier OGLAS Victron units drove a relay directly when solar surplus was stable — running an immersion heater, a pump, or another opportunistic load. That role has moved to the Smart Switch, which can take power-management data as one of several inputs (alongside other sensors, web APIs, and weather). The power-management sensor is now the source of the data; the Smart Switch is the actor.

This split means you can:

• Put the power-management sensor next to the MPPT (where the link is reliable) and the Smart Switches near the loads they’re driving.
• Have one power-management sensor inform any number of Smart Switches around the site.
• Run rules that combine power data with other inputs (“solar surplus and tank not full and between 9am and 5pm”).

Why your data, not VRM

Victron’s own VRM cloud is a fine product — but it’s a cloud product. With OGLAS power management:

• No VRM account required. No subscription tier, no internet dependency.
• All MPPT history lives on your local storage in plain formats — see Your data is your data.
• No telco link between the MPPT and your hub. The connection is local. See No telco dependency.

Pairs well with

• Smart Switch — the active counterpart. Power management produces the data; the Smart Switch decides whether to switch a load on the back of it.
• Large display — show MPPT watts, battery voltage, and Smart Switch state on the same screen as everything else.
• Tank level and Water Trough — the classic “is there enough sun to run the pump?” combination.
• Other power systems — Victron is first; if you run a different MPPT, inverter, or BMS, that’s a custom build.

2 - Smart Switch

The OGLAS Smart Switch is the active end of the network. Where the other sensors measure and report, the Smart Switch acts — turning a load on and off based on conditions you’ve defined, and reporting back not just whether it switched but whether the load is actually working.

What it does

A Smart Switch decides whether to be on or off using one or more of:

• Power-management data — reads incoming watts, battery state, and load from a power-management sensor (e.g. Victron MPPT). Run the relay on stable solar surplus.
• Sensor data — subscribe to readings from other OGLAS sensors. Tank dropped below 200 mm? Soil moisture below threshold? Battery bank above 90 %? React.
• Web / API data — when Wi-Fi is available, pull from a local server, MQTT broker, or HTTP endpoint. Used for off-property triggers that need external data.
• Weather data — forecast and current conditions from a weather API. “Run only when the next 6 hours are clear” is one rule that uses this.

Multiple inputs combine with AND/OR rules in the device config. None of this requires a cloud account — see Your data is your data.

Common deployments

• Water pump on solar surplus — only run the pump when the MPPT is producing more than the rest of the load needs and the destination tank isn’t already full.
• Generator starter — battery bank below 30 %, weather forecast says no sun for two days, and it’s between 9am and 5pm? Start the generator. Run for at most two hours, max once per day.
• Charge controller for opportunistic loads — divert excess solar to an immersion heater, tool-battery charger, or pre-cooling a fridge.
• Irrigation on dry soil + good weather — soil moisture below threshold and sun forecast for the next four hours.
• Frost protection — temperature dropping below 2 °C, fans on.
• Site equipment — a yard load (charger bank, extractor, compressor) on a schedule or a sensor condition, with current sensing to confirm it actually ran.

What it measures

A Smart Switch is also a sensor — when it’s switching a real load, it measures what’s happening:

• Current — is the pump actually drawing power, or did the contactor weld and the motor’s seized?
• Voltage — supply voltage at the load, not just at the panel.
• Faults — over-current, under-voltage, no-current-when-on, current-when-off.
• Duration — accumulated runtime per day, per week, per session.
• Power usage — energy consumed, integrated locally and reported.

Alerts you get

Both directions matter:

• Failure alerts — “supposed to be on, no current detected” — the pump didn’t start, the contactor didn’t pull in, the load is open-circuit.
• Working alerts — “pump just turned on for the third time today” — useful for confirming an irrigation cycle ran without you having to drive out and check.
• Threshold alerts — runtime exceeded daily budget, current spiked above expected, fault counter incremented.
• No-stop alerts — “should have turned off ten minutes ago, still on” — guards against the relay sticking closed.

Logging

Every switch action plus the measured load conditions is logged to the hub as a regular sensor reading. Over time you get:

• A timeline of when each switched load ran.
• Power usage per load — useful for identifying the energy hogs.
• Fault history — “this contactor has welded twice in three months, time to replace it”.
• Cost per cycle — energy used × your power cost, on each run.

Hardware

The Smart Switch includes:

• Relay output — solid-state or mechanical, sized for the load. Multiple outputs on larger variants.
• Current sensor — integrated, to measure whether the load is actually drawing power.
• Voltage sensor — supply voltage at the load.
• Long-range radio for comms back to the hub.
• Wi-Fi for web / API / weather inputs (when available).
• Bluetooth for direct Victron MPPT reads.

The Smart Switch runs from the same supply as the load it’s switching (or a separate aux supply for cleaner sensing).

Pairs well with

• Water Trough — trough drops, Smart Switch turns on the pump that fills it.
• Tank level — tank low, pump on; tank full, pump off.
• Vehicle Track — Vehicle Track flags low generator hours since service, Smart Switch refuses to auto-start it until you’ve serviced it.
• Power management — see solar production and Smart Switch action on the same dashboard.
• Bell — failure alert rings the homestead bell.

Building this into a larger site? That’s exactly what we do — start a custom build or email us.

3 - Power Monitoring

Power Management reads your solar charge controller. Power Monitoring reads everything else — because plenty of off-grid power doesn’t come from a Victron MPPT.

What it does

• Reads any source — mains feed, generator output, a battery bank via a shunt, or an individual circuit. AC or DC.
• Measures voltage, current, and energy — instantaneous draw and accumulated kWh, per source or per circuit.
• Finds the hogs — which load is quietly eating your battery overnight, and which circuit’s draw is creeping up.
• Logs locally — every reading to your hub in open formats, no utility portal — see Your data is your data.

Hardware

Current transformers (AC) or a DC shunt feeding an OGLAS node, sized to the circuit. Multiple channels for a switchboard; a single channel for one load.

Pairs well with

• Power Management — solar production on one side, consumption on the other, in one dataset.
• Smart Switch — shed a load when battery voltage drops, or start a generator when it does.
• Engine — pair generator run-hours with the energy it actually produced.

Building this into a larger site? That’s exactly what we do — start a custom build or email us.