# WM-Bus KCMCA6S series

## Summary
- WM-Bus module
- LCC form factor
- 25.4 mm × 14.0 mm × 2.9 mm
- Operating temperature range: -40°C to + 85°C

## Key features
- Frequency bands: 868 MHz, 169 MHz*, 433 MHz*
- 32 KB SRAM and 256 KB flash
- 1 USART, 1 SWD and 11 GPIO interfaces by default, with additional support for EUSART, I2C and ADC interfaces through pin multiplexing
- Stable network connection, strong anti-interference, reliable data transmission

## Overview
KCMCA6S & KCMCA6S-N are sub-GHz WM-Bus modules launched by Quectel, featuring an ARM Cortex-M33 processor with a frequency of up to 78 MHz, support WM-Bus protocol and comply with the EN 13757 standard, and integrate 32 KB RAM and 256 KB flash. 

KCMCA6S series modules are in a LCC form factor with an ultra-compact dimensions of 25.4 mm × 14.0 mm × 2.9 mm, which optimize the size and cost for end-products and are compatible with diverse designs.

KCMCA6S & KCMCA6S-N support multiple WM-Bus communication modes (T, C, S*, R*, N*, F*) and deliver efficient transmission through a low-power architecture, dynamic multi-mode switching, and flexible frequency configuration, alongside integrated multi-layer security mechanisms. As a widely adopted standard in Europe for smart metering, they are ideal for smart water/electricity/gas/heat meters and AMI (advanced metering infrastructure) systems, while also demonstrating strong potential in IoT connectivity scenarios.

## Product Brochure
[Download](https://www.quectel.com/content/uploads/2026/05/Quectel_Product_Brochure_V8.6.pdf) Quectel_Product_Brochure_V8.6.pdf

## Documentation and resources
### Hardware Development Resources
- **[Quectel_KCMCA6S_2D_Dimensions_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwm-bus-kcmca6s-series%2F)** - File Size: 135.13 KB
- **[Quectel_KCMCA6S_3D_Dimensions_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwm-bus-kcmca6s-series%2F)** - File Size: 676.96 KB
- **[Quectel_KCMCA6S_Footprint&Part_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwm-bus-kcmca6s-series%2F)** - File Size: 760.63 KB

### User Guide
- **[Quectel_KCMCA6S_Series_Firmware_Flashing_User_Guide_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwm-bus-kcmca6s-series%2F)** - File Size: 1.05 MB

## [Contact us](https://www.quectel.com/product/wm-bus-kcmca6s-series/#contact) if you have any questions.

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