> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt # Gravity: I2C Digital Wattmeter **Type:** Product page · **SKU:** SEN0291 · **Brand:** [DFRobot](https://core-electronics.com.au/brands/dfrobot-australia) **Page:** https://core-electronics.com.au/gravity-i2c-digital-wattmeter.html ([markdown](https://core-electronics.com.au/gravity-i2c-digital-wattmeter.html.md)) Gravity: I2C Digital Wattmeter is a high-resolution, high-precision, large-scale measurement module that can measure the voltage, current and power of various electronic... ## Pricing - **Price:** $11.35 (inc GST) — $10.32 AUD, exc GST - **Quantity discounts:** 6+ $9.80 (exc GST) · 12+ $9.39 (exc GST) ## Availability & dispatch - In stock, ships same business day if ordered before 2PM (Australia/Sydney). - We can dispatch 2 today, and up to 1100 more in 8–12 days. ## How to buy - **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=SEN0291:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart. - **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/SEN0291:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.) - **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there. - **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works) - **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt ## Description Gravity: I2C Digital Wattmeter is a high-resolution, high-precision, large-scale measurement module that can measure the voltage, current and power of various electronic modules and electrical equipment within 26V 8A, and the maximum relative error is no more than ±0.2% (A simple manual calibration is required before usage). It can be used for power consumption or battery life evaluation of [solar energy systems](https://www.dfrobot.com/category-226.html), [battery](https://www.dfrobot.com/category-92.html), [motors](https://www.dfrobot.com/category-51.html), [controller](https://www.dfrobot.com/category-184.html) or [electronic modules](https://www.dfrobot.com/category-219.html). The module adopts TI INA219 zero temperature drift current/power monitoring chip and 2W high power low temperature drift 10mO alloy sampling resistor. The voltage and current resolution can reach 4mV and 1mA respectively. Under the full scale measurement condition, the maximum relative error of voltage and current measurement can be superior to ±0.2%. It also provides four I2C addresses that can be configured via the 2P DIP switch. The module accurately measures bi-directional high-side currents (current flowing through the power supply or battery positive), which is especially useful in solar or battery fuel gauge applications where the battery needs to be charged and discharged. This status can be simply determined by positive or negative current readings. In the motor applications, the current can be monitored in real time by monitoring whether the motor current is too large due to overload. In addition, you can use this module to measure the power consumption of various electronic modules or the entire project to evaluate battery life. ### **Connection Diagram** ![Gravity: I2C Digital Wattmeter Connection Diagram (Arduino UNO)](https://core-electronics.com.au/attachments/localcontent/1_2936734e7f9.png) Gravity: I2C Digital Wattmeter Connection Diagram ([Arduino UNO](https://www.dfrobot.com/product-838.html)) ![Gravity: I2C Digital Wattmeter Connection Diagram (Raspberry Pi 3B)](https://core-electronics.com.au/attachments/localcontent/2_78649606f6a.png) Gravity: I2C Digital Wattmeter Connection Diagram ([Raspberry Pi 3B](https://www.dfrobot.com/product-1419.html)) ![Measuring the power consumption of the Gravity: pH meter](https://core-electronics.com.au/attachments/localcontent/3_32589c8ddee.png) Measuring the power consumption of the [Gravity: pH meter](https://www.dfrobot.com/product-1782.html) ![Monitor the power consumption of the solar panel, battery and outputs of a solar system](https://core-electronics.com.au/attachments/localcontent/4_70109c672f1.png) Monitor the power consumption of the [solar panel](https://www.dfrobot.com/category-226.html), battery and outputs of a solar system ### FEATURES - High precision, high resolution, large range, low temperature drift - Bidirectional current high side measurement - Compatible with 3.3V/5V controller - Sophisticated and compact, easy to embed in the project ### APPLICATIONS - Solar Power Management - Battery Fuel Gauge - Electronic Module Power Evaluation ### Specification - Input Voltage (VCC) : 3.3V~5.5V - Voltage Range (IN+ or IN- relative to GND): 0 ~ 26 V - Voltage Resolution: 4 mV - Voltage Relative Error: <±0.2% (Typical) - Current Range: 0 ~ ±8A (Bidirectional current) - Current Resolution: 1mA - Current Relative Error: <±0.2% (Typical, manual calibration required) - Power Range: 0 ~ 206 W - Power Resolution: 20 mW (Hardware) / 4 mW (Software) - Quiescent Current: 0.7 mA - Interface: Gravity I2C (logic level: 0-3.3V) - I2C Address: Four options 0x40, 0x41, 0x44, 0x45 - Dimension: 30.0mm\*22.0mm/1.18\*0.87 in - Weight: 4g ### Documents - Product wiki - More Documents ### Parts List - Gravity: I2C Digital Wattmeter x1 - XH2.54-4P Black Header x1 - Gravity-4P I2C/UART Sensor Wire x1 ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/s/e/sen0291-900x600.jpg)