esphome-ant-bms

ESPHome component to monitor and control a ANT-BMS via UART or BLE

Supported devices

• ANT-BLE16ZMUB, 16ZMUB00-220501A, 16ZMB0TB120A (by ant_bms_ble)
• ANT-BLE24BHUB, 24BHUB00-211026A, 24BH (by ant_bms_ble)
• 16ZMB-TB-7-16S-300A (7-16S, 300A, 2021-08-12)
• 24AHA-TB-24S-200A (10-24S, 200A, 2021-09-28)
• ANT 16S 100A (16S, 100A, 2020)
• ANT 24S 200A (8-24S, 200A, 2020)
• ANT 32S 300A (8-32S, 300A)

Untested devices

• ANT H-24S 180A

Requirements

• ESPHome 2024.5.0 or higher.
• Generic ESP32 or ESP8266 board

Schematics

                UART-TTL
┌──────────┐                ┌─────────┐
│          │<----- RX ----->│         │
│ ANT-BMS  │<----- TX ----->│ ESP32/  │
│          │<----- GND ---->│ ESP8266 │<-- 3.3V
│          │<----- 3.3V --->│         │<-- GND
└──────────┘                └─────────┘



│                ANT-BMS                 │
│                                        │
│  Comm                            Temp  │
└─[oooo]──[oooooooo]──[oooooooo]──[oooo]─┘
   ││││
   ││││      (ESP32)    /    (ESP8266)
   ││││
   │││└─ TXD (GPIO16)        (GPIO4)
   ││└── RXD (GPIO17)        (GPIO5)
   │└─── GND (GND)           (GND)
   └──── VCC (3.3V)          (3.3V)

The connector is a 4 Pin JST 1.25mm. It's important to connect VCC too because the BMS doesn't respond/start if you connect TXD, RXD and GND only.

#1 (comment)

Installation

You can install this component with ESPHome external components feature like this:

external_components:
  - source: github://syssi/esphome-ant-bms@main

or just use the esp32-example.yaml as proof of concept:

# Install esphome
pip3 install esphome

# Clone this external component
git clone https://github.com/syssi/esphome-ant-bms.git
cd esphome-ant-bms

# Create a secrets.yaml containing some setup specific secrets
cat > secrets.yaml <<EOF
wifi_ssid: MY_WIFI_SSID
wifi_password: MY_WIFI_PASSWORD

mqtt_host: MY_MQTT_HOST
mqtt_username: MY_MQTT_USERNAME
mqtt_password: MY_MQTT_PASSWORD
EOF

# Validate the configuration, create a binary, upload it, and start logs
# If you use a esp8266 run the esp8266-examle.yaml
esphome run esp32-example.yaml

Example response all sensors enabled

[sensor:125]: 'ant-bms total voltage': Sending state 54.10000 V with 2 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 1': Sending state 4.13800 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 2': Sending state 4.13800 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 3': Sending state 4.13500 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 4': Sending state 4.13800 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 5': Sending state 4.13800 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 6': Sending state 4.13600 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 7': Sending state 4.13600 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 8': Sending state 4.13600 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 9': Sending state 4.13400 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 10': Sending state 4.13700 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 11': Sending state 4.13600 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 12': Sending state 4.13700 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms cell voltage 13': Sending state 4.14000 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms current': Sending state 0.00000 A with 1 decimals of accuracy
[sensor:125]: 'ant-bms soc': Sending state 100.00000 % with 0 decimals of accuracy
[sensor:125]: 'ant-bms total battery capacity setting': Sending state 39.00000 Ah with 2 decimals of accuracy
[sensor:125]: 'ant-bms capacity remaining': Sending state 38.99547 Ah with 2 decimals of accuracy
[sensor:125]: 'ant-bms battery cycle capacity': Sending state 575.37402 Ah with 2 decimals of accuracy
[sensor:125]: 'ant-bms temperature 1': Sending state 21.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms temperature 2': Sending state 21.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms temperature 3': Sending state 20.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms temperature 4': Sending state 20.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms temperature 5': Sending state 20.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms temperature 6': Sending state 20.00000 °C with 0 decimals of accuracy
[sensor:125]: 'ant-bms charge mosfet status code': Sending state 1.00000  with 0 decimals of accuracy
[text_sensor:067]: 'ant-bms charge mosfet status': Sending state 'On'
[sensor:125]: 'ant-bms discharge mosfet status code': Sending state 1.00000  with 0 decimals of accuracy
[text_sensor:067]: 'ant-bms discharge mosfet status': Sending state 'On'
[sensor:125]: 'ant-bms balancer status code': Sending state 0.00000  with 0 decimals of accuracy
[text_sensor:067]: 'ant-bms balancer status': Sending state 'Off'
[sensor:125]: 'ant-bms power': Sending state 0.00000 W with 1 decimals of accuracy
[sensor:125]: 'ant-bms min cell voltage': Sending state 4.14000 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms max cell voltage': Sending state 4.13400 V with 3 decimals of accuracy
[sensor:125]: 'ant-bms average cell voltage': Sending state 4.13600 V with 2 decimals of accuracy
[sensor:125]: 'ant-bms battery strings': Sending state 13.00000  with 0 decimals of accuracy
[switch:037]: 'ant-bms charging': Sending state ON
[switch:037]: 'ant-bms discharging': Sending state ON
[switch:037]: 'ant-bms balancer': Sending state OFF
[text_sensor:067]: 'ant-bms total runtime formatted': Sending state '6d 7h '
[sensor:124]: 'ant-bms total runtime': Sending state 546592.00000 s with 0 decimals of accuracy

Protocol

Status frame

Offset	Len	Example value	Field	Decoded value	Coeff./Unit
0	4	0xAA 0x55 0xAA 0xFF	Header
4	2	0x02 0x1D	Total voltage	541 * 0.1 = 54.1V	0.1 V
6	2	0x10 0x2A	Cell voltage 1	4138 * 0.001 = 4.138V	0.001 V
8	2	0x10 0x2A	Cell voltage 2	4138 * 0.001 = 4.138V	0.001 V
10	2	0x10 0x27	Cell voltage 3	4135 * 0.001 = 4.135V	0.001 V
12	2	0x10 0x2A	Cell voltage 4		0.001 V
14	2	0x10 0x2A	Cell voltage 5		0.001 V
16	2	0x10 0x28	Cell voltage 6		0.001 V
18	2	0x10 0x28	Cell voltage 7		0.001 V
20	2	0x10 0x28	Cell voltage 8		0.001 V
22	2	0x10 0x26	Cell voltage 9		0.001 V
24	2	0x10 0x29	Cell voltage 10		0.001 V
26	2	0x10 0x28	Cell voltage 11		0.001 V
28	2	0x10 0x29	Cell voltage 12		0.001 V
30	2	0x10 0x2C	Cell voltage 13		0.001 V
32	2	0x00 0x00	Cell voltage 14		0.001 V
34	2	0x00 0x00	Cell voltage 15		0.001 V
36	2	0x00 0x00	Cell voltage 16		0.001 V
38	2	0x00 0x00	Cell voltage 17		0.001 V
40	2	0x00 0x00	Cell voltage 18		0.001 V
42	2	0x00 0x00	Cell voltage 19		0.001 V
44	2	0x00 0x00	Cell voltage 20		0.001 V
46	2	0x00 0x00	Cell voltage 21		0.001 V
48	2	0x00 0x00	Cell voltage 22		0.001 V
50	2	0x00 0x00	Cell voltage 23		0.001 V
52	2	0x00 0x00	Cell voltage 24		0.001 V
54	2	0x00 0x00	Cell voltage 25		0.001 V
56	2	0x00 0x00	Cell voltage 26		0.001 V
58	2	0x00 0x00	Cell voltage 27		0.001 V
60	2	0x00 0x00	Cell voltage 28		0.001 V
62	2	0x00 0x00	Cell voltage 29		0.001 V
64	2	0x00 0x00	Cell voltage 30		0.001 V
66	2	0x00 0x00	Cell voltage 31		0.001 V
68	2	0x00 0x00	Cell voltage 32		0.001 V
70	4	0x00 0x00 0x00 0x00	Current	0.0 A	0.1 A
74	1	0x64	SOC	100 %	1.0 %
75	4	0x02 0x53 0x17 0xC0	Total Battery Capacity Setting	39000000	0.000001 Ah
79	4	0x02 0x53 0x06 0x11	Battery Capacity Remaining		0.000001 Ah
83	4	0x00 0x08 0xC7 0x8E	Battery Cycle Capacity	575374 * 0.001 = 575.374 Ah	0.001 Ah
87	4	0x00 0x08 0x57 0x20	Uptime in seconds	546.592 s	1.0 s
91	2	0x00 0x15	Temperature 1	21°C	1.0 °C
93	2	0x00 0x15	Temperature 2	21°C	1.0 °C
95	2	0x00 0x14	Temperature 3	20°C	1.0 °C
97	2	0x00 0x14	Temperature 4	20°C	1.0 °C
99	2	0x00 0x14	Temperature 5	20°C	1.0 °C
101	2	0x00 0x14	Temperature 6	20°C	1.0 °C
103	1	0x01	Charge MOSFET Status
104	1	0x01	Discharge MOSFET Status
105	1	0x00	Balancer Status
106	2	0x03 0xE8	Tire length		mm
108	2	0x00 0x17	Number of pulses per week
110	1	0x01	Relay switch
111	4	0x00 0x00 0x00 0x00	Current power	0W	1.0 W
115	1	0x0D	Cell with the highest voltage	Cell 13
116	2	0x10 0x2C	Maximum cell voltage	4140 * 0.001 = 4.140V	0.001 V
118	1	0x09	Cell with the lowest voltage	Cell 9
119	2	0x10 0x26	Minimum cell voltage	4134 * 0.001 = 4.134V	0.001 V
121	2	0x10 0x28	Average cell voltage	4136 * 0.001 = 4.136V	0.001 V
123	1	0x0D	Cell count	13
124	2	0x00 0x00	Discharge MOSFET, voltage between D-S	0.1 V
126	2	0x00 0x73	Drive voltage (discharge MOSFET)		0.1 V
128	2	0x00 0x6F	Drive voltage (charge MOSFET)		0.1 V
130	2	0x02 0xA7	When the detected current is 0, the initial value of the comparator
132	4	0x00 0x00 0x00 0x00	Battery is in balance bitmask (Bit 1 = Cell 1, Bit 2 = Cell 2, ...)
136	2	0x11 0x62	System log / overall status bitmask?
138	2	0x0B 0x00	CRC

Known issues

• ESP32: Adding all supported sensors can lead to a stack overflow / boot loop. This can be solved by increasing the stack size. (#36)
• A command queue / command scheduling would be nice. At the moment changing settings via the switch entities isn't reliable.

Debugging

If this component doesn't work out of the box for your device please update your configuration to enable the debug output of the UART component and increase the log level to the see outgoing and incoming serial traffic:

logger:
  level: DEBUG

uart:
  id: uart_0
  baud_rate: 19200
  rx_buffer_size: 384
  tx_pin: ${tx_pin}
  rx_pin: ${rx_pin}
  debug:
    direction: BOTH

References

• https://github.com/klotztech/VBMS/wiki/Serial-protocol
• esphome/feature-requests#1396
• https://github.com/imval/AntBMS/blob/main/AntBMS.cpp
• https://diysolarforum.com/threads/for-those-of-you-looking-to-monitor-your-ant-bms-with-pi3-via-bluetooth.6726/
• https://github.com/RoboDurden/AntBms-Arduino