Expandable 6 Channel ESP32 Energy Meter Add-on Board

Description

The Expandable 6 Channel ESP32 Energy Meter Add-on Board can measure the amount of current being used by 6 circuits at a time! Much like our Split Single Phase Energy Meter, the 6 channel energy meter uses current transformers to measure current being used by any circuit, and an AC transformer to measure voltage. An ESP32 dev board plugs directly into the energy meter to process the meter data and send it over WiFi.

This listing is for the Add-on board only – a main board and an ESP32 (see options below) is required to use this board.

Up to 6, 6 channel add-on boards can stack on top of the main board to allow you to monitor up to 42 current channels (please see note below for ESPHome) in 16-bit resolution, in real time, all at once! Each add-on board can measure an additional voltage channel.

Backorder Update: 9/28/21 – The new batch of add-on boards will arrive and begin shipping on 10/11. However, these are almost all sold already! Order now so you do not have to wait for the next batch, which will take longer than usual because of the chip shortage.

Backorder Update: 10/4/21 – The next batch mentioned above is already sold out! Please add your email to the notification list to be notified when more will be available.

Features:

• Plugs in to the 6 Channel Energy Meter Main Board
• Samples 6 current channels & optionally 1 additional voltage channel (requires additional AC transformer to measure additional voltage)
• Add-on boards (up to 6) can expand the meter up to 42 current channels & 8 voltage channels
• Uses 2 Microchip ATM90E32AS – 3 current channels & 1 voltage per IC
• For each current channel the following can also be calculated by the meter:
  • Active Power
  • Reactive Power
  • Apparent Power
  • Power Factor
  • Frequency
  • Temperature
• Uses standard current transformer clamps to sample current
• 22ohm burden resistors per current channel
• Includes built-in buck converter to power ESP32 & electronics
• 2 IRQ interrupts, and 1 Warning outputs
• Zero crossing outputs
• Energy Pulse outputs per IC (4 per IC x2)
• SPI Interface
• Measurement Error: 0.1%
• Dynamic Range: 6000:1
• Gain Selection: Up to 4x
• Voltage Reference Drift Typical (ppm/°C): 6
• ADC Resolution (bits): 16

What you’ll need:

• Expandable 6 Channel ESP32 Energy Meter Main Board – add-on boards can not function properly without a main board
• Current Transformers (depending on your application)
  • SCT-006 20A/25mA micro CT (6mm opening – 3.5mm connectors)  – these are great if you have a lot of 15A circuits that you want to monitor
  • SCT-010 80A/26.6mA mini CT (10mm opening – 3.5mm connectors)
  • SCT-013-000 100A/50mA (13mm opening – 3.5mm connectors)
  • SCT-016 120A/40mA (16mm opening – 3.5mm connectors) – for monitoring mains
  • Others can also be used as long as they’re rated for the amount of power that you are wanting to measure, and have a current output no more than 720mA.
• AC Transformer: Jameco Reliapro 9v or 12v. The positive pin must be 2.5mm (some are 2.1)
• ESP32 (choose one):
  • NodeMCU
  • Espressif DevKitC
  • Espressif ESP32-DevKitC-32U or ESP32-DevKitC-VB (WROVER) if you need better wifi reception (don’t forget the antenna)
  • Anything else with the same pinouts as the above, which are usually 19 pins per side with 3v3 in the upper left & CLK in the lower right
• A 3d printed case (optional)
• Software (choose one):
  • Our custom version of EmonESP and the ATM90E32 Arduino library
  • ESPHome. Details on integration with Home Assistant are located here.
    • Note: Currently ESPHome cannot support more than 3 add-on boards (with each phase having a current and power sensor) on one ESP32. If you need more than 3 add-on boards to work with 1 ESP32, they must be configured to output power only, otherwise the ESP32 will run out of stack space and fail to boot. 
  • Libraries for CircuitPython & MicroPython