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VA Meter

SKU:K136

Description

VA Meter is a professional programmable high-precision power meter designed for accurate voltage and current measurement. This product is based on the M5StampS3 main control module, supporting WiFi functionality. It features two serially connected INA226 current and voltage measurement circuits, providing current detection resolutions of 2.5uA and 250uA, and supports a measurement range of 0-5A and 5-24V (1-24V in isolation mode). The product can be powered through a USB-C interface or Base terminal input and includes built-in power and signal isolation. Users can select between isolated measurement via USB power or non-isolated measurement using direct power through a toggle switch, catering to different application needs. The accompanying expansion BASE includes relay on/off control and a Grove port for secondary development.

Additionally, the instrument supports OTA firmware upgrades and USB MSC/OTG functionality, allowing users to edit and view data and configuration files stored in the main control file system on a PC. M5 also provides a free online data API interface, enabling users to upload test data to the EZData platform for remote access and browsing, significantly simplifying IoT application development. The VA Meter is a versatile and developer-friendly instrument, ideal for engineering projects requiring precise current and voltage measurements, as well as fields such as industrial automation, equipment monitoring, and smart grids.

Tutorial

VAMeter Quick Start
Quick Start
This tutorial will introduce you to the VA Meter device tutorial & Get started quickly
Download Mode
If you want to enter download mode, press and hold the G0 button on StampS3 before turning it on, then release it after powering it on.
schematics

Features

  • High precision current detection (2.5uA/250uAResolution switching)
  • Wide voltage input (5-24V)
  • Cloud (EZData) data display
  • PD input (internal does not contain PD decoy)
  • Multiple power supply modes (PD INPUT/StampS3/External terminal)
  • Power is isolated from signal
  • USB MSC/OTG function
  • Open source hardware and software
  • OTA Upgrade

Includes

  • 1x VA Meter
  • 1x VA Meter Base
  • 2x 3.81-2P terminal
  • 4x Hanger (small)

Applications

  • Industrial Automation
  • Equipment Monitoring
  • Power Testing and Analysis
  • Internet of Things (IoT) Devices
  • Remote Monitoring and Data Collection

Specification

Resources Parameters
Power detection chip INA226
SoC ESP32S3FN8@Xtensa® 32-bit LX7 dual-core processor up to 240 MHz
Flash 8MB Flash
PSRAM N/A
Wi-Fi IEEE 802.11 b/g/n (2.4 GHz Wi-Fi)
Screen 1.3 Inch@ 240*240 Pixel
Screen Driver ST7789
PD Input Power 5-24V@0-5A
Current detection resolution 2.5uA/250uA
Current sampling error Small current (1-100mA) sampling error: 1.01%
Large current (100mA-5A) Sampling error: 0.94%
uA-level current sampling error: 0.69%
Power Consumption (factory firmware) STAMPS3 USB power supply: DC5V/123.5mA
PD INPUT power supply: DC5V/118mA     DC12V/66.8mA     DC24V/26mA
PD OUTPUT capability DC24V/3A 68℃
DC24V/5A 92℃
USER interaction Rotary encoder switch, reset button, boot button and board
INA226 Communication Address Two detection chips INA226:0x40/0x41
Relay DC 5-24V @5A
Operating Temperature 0-40°C
Product Size VAMeter 36*36*14.7mm
VAMeter 36*36*20.3mm
Rail Fastening 51.5*48*5.5mm
Package Size 150*93*30mm
Product Weight VAMeter:17.7g VAMeter Base:25.8g
Rail Fastening 4g
Package Weight 68.1g

EasyLoader

EasyLoader is a concise and fast program writer, which has a built-in case program related to the product. It can be burned to the main control by simple steps to perform a series of function verification.

Download VA Meter Factory Firmware Easyloader

M5 EZData Cloud Platform example

schematics

PinMap

  • VAMeter(INA226 & BUZZER)
Note
INA226(0x40) and INA226(0x41) are used for measurements of different resolutions and sizes
M5STAMPS3 G5 G6 G41 G40 G14
INA226(0x40) FSDA FSCL ALERT1
INA226(0x41) FSDA FSCL ALERT2
BUZZER BUZ_PWM
  • VAMeter Extra output pin
M5STAMPS3 G10 G9 G8 G42
Extra output pin EXT_G10 EXT_G9 EXT_G8 EXT_G42
  • VAMeter Base
M5STAMPS3 G10
Relay GPIO10_REL
  • Grove
M5STAMPS3 G9 G8 VCC GND
Grove GPIO9 GPIO8 SYS_5V FGND

VAMeter compared to other brands

schematics

Schematic

  • VAMeter
schematics
  • VAMeter Base
schematics
  • VAMeter internal circuit logic diagram
schematics

VA Meter Schematic PDF

VA Meter Base Schematic PDF

VAMeter Base PCB Download

Module Size

module size

Examples

Arduino

Video

  • VAMeter Function Introduction