Reliable and Flexible Data Logging with Perseus for Optimal Monitoring

Reliable and Flexible Data Logging with the Perseus Logger

Recording and storing measured values is one of the most vital features in modern remote monitoring systems. HW group’s Perseus platform provides a unified firmware across its devices, all equipped with a powerful logging function. In this article, we explore how the logger works within Perseus units, key technical details, and tips to optimize your monitoring setup.

Simple Interface and Basic Logger Settings

The Perseus logging interface is straightforward and user-friendly. In the “Settings” section, you can enable or disable logging and set a universal logging interval that applies to all variables. The “Export” section lets you configure the time range, data limits, and timescale for exporting logged data. You can also choose to export data in reverse order, starting from the most recent records. Supported export formats include CSV and JSON, making it easy to integrate with other monitoring systems.

Key Features of the Perseus Logger

The Perseus logger is power-independent. This means if the device powers down due to an outage, logging automatically resumes upon restart without losing previous data. Additionally, the logger records not only raw values but also results from any calculations performed on variables. The logging interval affects how data appears in graphs. Depending on the criticality of your data, you should choose an interval that balances detail and storage.

Advanced Logging Control with the Action: Log Feature

For precise control over what and when to log, the “Action: Log” feature uses two types of triggers:

• Condition filters: Logs data only when variable states change, e.g., from OK to High Alarm.
• Scheduler: Allows setting specific date and time ranges to log selected variables, like certain days or hours.

This enables fine-tuned, conditional logging tailored to your needs.

Logger Capacity and Performance

Each Perseus unit comes with 32 MB of logging memory. Logging one variable every minute yields around 647 days (nearly two years) of continuous data storage. Increasing the interval to every ten minutes extends this to over 17 years. Data can be downloaded via the web interface or accessed through the API. The API uses HTTP GET commands and supports filtering by variable, time range, limit, order, and timescale, providing flexible data retrieval.

Summary of Main Features

• Power-independent logging with automatic recovery after outages
• Logging of calculated values, not just raw data
• Flexible period settings and export options
• Precise control via condition filters and scheduler triggers
• Large memory capacity for long-term data storage
• API access for easy integration with monitoring software

Frequently Asked Questions (FAQ)

1. How long can the Perseus logger store data?

With 32 MB memory and one-minute intervals, it stores approximately 647 days of data.

2. What happens during a power outage?

The logger automatically resumes recording upon device restart without data loss.

3. Can I log only specific variables at certain times?

Yes, the “Action: Log” feature lets you schedule logging based on time or conditions.

4. In which formats can I export logged data?

Data exports are available in CSV and JSON formats.

5. How do I access logger data via API?

Use HTTP GET commands with parameters for variables, time ranges, order, and format.