n8n Transformer Overload Early Warning Alert (HTTP API + Email)

Get an early warning when transformer overload risk rises—automatically

This n8n workflow checks transformer load and temperature every 15 minutes, calculates an overload risk score with a projected time-to-overload, and sends an email alert via SMTP only when the risk level is High or Critical.

What this workflow does

• Runs on a 15-minute schedule using a schedule trigger.
• Sets transformer metadata (Transformer ID, Substation, and Rated Capacity) for consistent downstream requests and calculations.
• Fetches required data through three HTTP APIs in parallel:
  • Real-time load
  • Real-time temperature/environmental readings
  • 30-day historical load and incident data
• Merges the datasets into a single record, then briefly waits to buffer before analysis.
• Calculates:
  • Load percentage
  • Temperature and trend-based subscores
  • An overall 0–100 overload risk score and a risk level
  • An estimated hours-to-overload prediction
• Conditional notification: if risk is High or Critical, it waits briefly for a cooldown and then sends an alert email with the risk level and score; otherwise, it ends without emailing.

Use cases

• SaaS operators monitoring transformer health across multiple sites and needing consistent, automated threshold alerts.
• Automation engineers integrating SCADA/sensor systems and historical incident trends into a proactive early warning flow.
• Asset teams who want clear overload risk scoring and time-to-overload projections before critical conditions occur.

Technical details

• HTTP API integrations (3 parallel requests) with configurable HTTP Header Auth and endpoint base URLs.
• SMTP email sending via n8n SMTP credentials (configurable from/to and email body settings).
• Core n8n nodes used: if, set, code, no op, wait, merge.

To get started, update the API base URLs/endpoints, your HTTP header auth credentials, the SMTP settings, and the transformer ID/substation/rated capacity to match your asset.