EMC2101 Fan Controller and Temperature sensor¶
The emc2101
component allows you to control a cooling fan from ESPHome (datasheet). It also provides temperature
sensors and a tachometer. The fan can be controlled either by a PWM signal or by outputing a DC voltage
using its DAC.
The I²C Bus is required to be set up in your configuration for this sensor to work.
Note
Original image at https://learn.adafruit.com/assets/97827 created by by user Bryan Siepert under Creative Commons BY-SA 3.0 and modified for this documentation.
EMC2101 Component¶
# Example configuration entry
emc2101:
pwm:
resolution: 8
Configuration variables:¶
address (Optional, int): Manually specify the I²C address of the sensor. Defaults to
0x4C
.inverted (Optional, boolean): Inverts the output so 0 means 100% duty cycle and 1 means 0%. Defaults to
false
.pwm (Optional): Enable PWM output.
resolution (Optional, int): Determines effective resolution and the frequency of the PWM signal. Defaults to
23
.divider (Optional, int): Value for the frequency divider. Defaults to
1
.
dac (Optional): Enable DAC output.
conversion_rate (Optional, string): The number of digital to analog conversions perfomed per second. One of
1/16
,1/8
,1/4
,1/2
,1
,2
,4
,8
,16
,32
. Defaults to16
.
The PWM signal frequency is determined by the following formula:
And the PWM resolution, the steps in the duty cycle, is calculated by the following formula:
So, with the default values the PWM signal will have a frequency of 7.83KHz and a resolution of 2.17%. The maximum
resolution value is 31
which will configure a frequency of 5.81KHz with a resolution of 1.61%.
EMC2101 Output¶
output:
- platform: emc2101
id: fan_duty_cycle
Configuration variables:¶
id (Required, ID): The ID to use for code generation, and for reference by dependent components.
Note
When using the emc2101
output with a Speed Fan it is advised to configure the speed_count
as twice the resolution so the number of speeds in the fan matches the number of steps in the fan controller.
EMC2101 Sensors¶
sensor:
- platform: emc2101
internal_temperature:
id: internal_temperature_sensor
name: "Internal Temperature Sensor"
speed:
id: speed_sensor
name: "Speed Sensor"
duty_cycle:
id: duty_cycle_sensor
name: "Duty Cycle Sensor"
update_interval: 5s
Configuration variables:¶
internal_temperature (Optional): The internal temperature sensor. All options from Sensor.
external_temperature (Optional): The external temperature sensor. More accurate but it needs an additional transistor to be installed. All options from Sensor.
speed (Optional): The fan speed sensor in RPMs. All options from Sensor.
duty_cycle (Optional): Duty cycle sensor. All options from Sensor.
update_interval (Optional, Time): The interval to check the sensor. Defaults to
60s
.