Understanding how much history your gateway keeps is the difference between having a complete audit trail and having "black holes" in your energy reports.
1. Why On-Device Storage Matters (The "Data Sovereignty" Rule)
Storing data locally on your gateway ensures that your facility remains ISO 50001 compliant regardless of your network status.
- Audit Readiness: For technical audits, you need historical context. If a gateway fails to store data during a network outage, you lose the ability to compare Year-over-Year (YoY) performance.
- Speed of Access: Pulling data from an inbuilt server is significantly faster than waiting for a cloud dashboard to fetch thousands of data points over a slow internet connection.
2. History Capacity by Model Tier
| Model Tier | Storage Type | History Duration | Best For |
|---|---|---|---|
| Economic Model | Buffer Memory | 3–7 Days | Small retail/offices. |
| Beginner Model | Inbuilt Server | 1 Year | SMBs basic reporting. |
| Advantage Model | High-Capacity Server | 2 Years | Industrial plants YoY efficiency. |
| Promax PLC Model | Enterprise Storage | 3 Years | Critical infrastructure & diagnostics. |
3. Security: The "Zero-Access" Advantage
By keeping 2–3 years of history on the device itself, you eliminate the need to constantly upload sensitive industrial patterns to third-party servers.
- Encrypted Storage: Data is stored using industrial-grade encryption, protecting your production secrets.
- Physical Redundancy: Most gateways allow for a USB Export, allowing you to walk away with years of energy intelligence even if the network is down.
The Bottom Line
Choosing a gateway with at least 2 years of on-device storage ensures that your ROI is backed by an unbreakable audit trail, giving you the historical proof you need to drive down energy costs year after year.