Why Monitor a Generator Remotely?
A backup generator is, by definition, a piece of equipment that must start up the very moment everything else fails. A generator that fails to start during a power outage has failed in its mission, potentially with serious consequences (hospitals, data centers, pumping stations, telecom towers).
Paradoxically, backup generators are often the least closely monitored pieces of equipment: they are located in utility rooms, are rarely started up, and their failure is not discovered until the next power outage. Remote monitoring radically changes this situation.
Key Metrics Monitored
Electrical (Alternator)
- Voltage per phase (L1, L2, L3): detection of imbalance or under/overvoltage
- Current per phase: detection of overload or load imbalance
- Frequency: 50 Hz ± 2% for sensitive applications
- Active power (kW) and reactive power (kVAR): load monitoring
- Energy generated (kWh): billing or reporting
Diesel Engine
- Fuel level (liters and %) with range calculation
- Oil pressure (bar): alarm if < minimum threshold
- Coolant temperature (°C): overheating alarm
- Starter battery voltage (V): faulty battery = engine won’t start
- Engine RPM: check for proper acceleration
Controller and Control
- Mode (automatic / manual / off)
- Grid/generator set coupling status (ATS position)
- Controller alarm codes (via Modbus)
- History of starts and durations
Monitoring Architecture for a Fleet of Generators
| Component | Role |
|---|---|
| Field Sensors | Measures fuel level, current, and temperature |
| Generator Set Controller (DSE/ComAp) | Centralizes engine and alternator measurements |
| 4G IoT Gateway | Reads data from the controller via Modbus, transmits it to the cloud |
| Cloud Platform | Dashboards, alerts, reports, remote control |
| On-Call Support | Receives SMS/email alerts in the event of a malfunction |
Use Case: Multi-Operator Telecom Sites
Base stations (BTS, NodeB, eNodeB) are always equipped with a backup generator to ensure uninterrupted service in the event of a power outage. A national telecom operator manages thousands of sites under strict constraints:
- Fuel: Some sites consume 15 to 20 L/h and can run out of fuel within 24 hours if the outage lasts that long.
- Starting battery: Silent failure until the next outage.
- Periodic tests: required by specifications, but often poorly documented.
Centralized monitoring allows a team of 3 to 5 people to oversee more than 500 sites and trigger targeted fuel replenishments only where necessary, rather than conducting systematic rounds.
Alerts and Escalations
A properly configured alert system distinguishes between:
- Warning: Fuel at 60%, battery at 24 V (voltage normal but requires monitoring).
- Alert: Fuel at 30%, generator in minor alarm (on-call staff notified).
- Critical alarm: Generator fails to start, fuel at 10%, engine temperature > 100 °C (automatic phone call to the night on-call staff).
- Escalation: If the on-call staff does not respond within 15 minutes, the technical manager is contacted.