Atoch S1BWP ESPHome

An ESPHome script that frees your S1BWP power meter from the Tuya cloud and enables fully local control via Home Assistant.

Note

This project is primarily aimed at the new S1BW(P) versions that are based on the AC6321A microcontroller and T1-2S-NL WiFi module. Other S1 variants with WiFi support may or may not work.

The dashboard YAML can be found in ha-dashboard.yaml.

Install

1. Install ESPHome and configure project

Support for the BK7238 in libretiny is still experimental and currently only works in ESPHome 2026.02.04 or earlier, see PR #360.

# Install esphome
pip3 install esphome==2026.02.04

# Clone this external component
git clone https://github.com/1RandomDev/atorch-s1bwp-esphome.git
cd atorch-s1bwp-esphome

# Copy example config
cp secrets.yaml.sample secrets.yaml

# Validate configuration and compile
esphome compile atorch-s1bwp-esphome.yaml

2. Connect to the WiFi module

Caution

Do not connect the device to the mains while hooked up to a computer, everything on the low voltage side is live!

Connect a USB to serial adapter to RX1/TX1 (the existing connections to the devices PCB need to be broken) and power the device either via 5v or 3.3v. See Board Images for reference.

3. Backup the original firmware

This backup is needed if you ever want to install firmware updates for the primary MCU, which are currently only available through the SmartLife app.

The flash contents of the BK7238 can be read using ltchiptool or BK7231GUIFlashTool. After the backup process is completed, do NOT reset or power cycle the device. If the device is left in programming mode the next step will be a lot easier.

4. Flash ESPHome via UART

esphome run atorch-s1bwp-esphome.yaml

Board Images

Available Tuya data points

The following Tuya data points were identified using TuyaMCUAnalyzer.

DP Id	Type	Description	Unit/Range	Prescaler	Writable
1	Boolean	Actual relay state
9	Integer	Countdown until relay toggle (cannot be used in mode AUTO)	0-360000 s		X
18	Integer	Current	A	* 0.001
19	Integer	Power	W	* 0.01
20	Integer	Voltage	V	* 0.01
101	Integer	Electricity price (only price mode A)	0-999.99	* 0.01	X
102	Integer	Calculated electricity cost		* 0.0001
103	Integer	Protections trigger delay	0-2 s	* 0.1	X
104	Integer	Over voltage protect threshold	0.1-275 V	* 0.1	X
105	Integer	Over current protect threshold	0.01-20 A	* 0.01	X
106	Integer	Over power protect threshold	1-4500 W		X
107	Enum	Language	0=Chinese 1=English		X
108	Integer	Screen brightness	1-9		X
109	Integer	Screen brightness standby	1-9		X
110	Integer	Standby time	3-99 s		X
111	Boolean	Key beep			X
112	Enum	Switch mode	0=Controllable 1=Normally on		X
113	Boolean	Clear data (can only be set to true, no feedback)			X
114	Boolean	WiFi reset (can only be set to true, no feedback)			X
115	Boolean	System factory reset (can only be set to true, no feedback)			X
116	Boolean	Toggle screen rotation (can only be set to true, no feedback)			X
117	Enum	Standby screen	0=Original 1=Measurement 2=Calendar 3=Screen OFF		X
118	Enum	Current screen	same order as on device		X
119	Integer	Mode: Smart Poweroff A - Power below	1-999 W		X
120	Integer	Mode: Smart Poweroff A - Delay until power off	1-99 min		X
121	Integer	Mode: Smart Poweroff B - Power above	1-999 W		X
122	Integer	Mode: Smart Poweroff B - Delay until power off	1-99 h		X
123	Integer	Energy	kWh	* 0.001
124	Integer	Last set time from multiple modes (use dedicated datapoints instead)	s
125	Integer	Mode: Timing Off - Time	1-5999 min	/ 60	X
126	Integer	Mode: Timing On - Time	1-5999 min	/ 60	X
127	Integer	Mode: Timing Cycle - On	1-5999 min	/ 60	X
128	Integer	Mode: Timing Cycle - Off	1-5999 min	/ 60	X
129	Integer	Mode: Timing Countdown - Countdown On	1-5999 min	/ 60	X
130	Integer	Mode: Timing Countdown - Countdown Off	1-5999 min	/ 60	X
131	Enum	Selected relay state	0=ON 1=OFF 2=AUTO		X
132	Enum	Poweroff reason/fault (set to 0 to clear)	0=none 1=over voltage 2=over current 3=over power 4=smart poweroff A 5=smart poweroff B 6=unknown 7=timing off 8=unknown 9=unknown 10=low voltage		X
133	Integer	Frequency	Hz	* 0.01
134	Integer	Power factor		* 0.01
135	Integer	CPU temperature	°C
136	Enum	Price mode	0=Price A 1=Price B 2=Price C		X
137	Integer	Fault recovery time	1-99 min		X
138	Enum	Power-up relay state	0=ON 1=OFF 2=Memory		X
139	Boolean	Poweroff relay on fault			X
140	Boolean	Fast refresh measurements (turns itself off automatically after 5min)	true=every 1s false=every 5min		X
141	Integer	Low voltage protect threshold	0.1-275 V	* 0.1	X
142	Integer	Fault recovery countdown	s