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Power Meter

#Power Meter

2 articles
Hardware / IoT
No kWh Meter? Estimate Daily Electricity Costs from Current
Hardware

No kWh Meter? Estimate Daily Electricity Costs from Current

Notes on converting CT current readings into energy usage and daily time-of-use electricity costs, from the three-phase power formula and the sampling interval built into it, through skipping outages and separating peak from off-peak with epoch arithmetic, to a daily summary table that made the web page seven times faster.

#energy#power-meter#electrical#modbus
10 min read·15 Oct
Reading a DTSU666 3-Phase Meter with Raspberry Pi over Modbus RS485
Linux

Reading a DTSU666 3-Phase Meter with Raspberry Pi over Modbus RS485

Notes on connecting a DTSU666 Smart Power Sensor to a Raspberry Pi over RS485, reading 3-phase electrical measurements from multiple meters using Modbus RTU, decoding 32-bit floats correctly, and storing them in SQLite/MySQL before exporting through MQTT and a REST API, including a negative-value bug I ran into myself

#modbus#rs485#iot#dtsu666
11 min read·19 Jul