The hardware<\/h2>\n\n\n\n The power plug uses the eps8266 as its main IC, and because there is a header that exposes the pins needed for programming, reprograming it is really easy.<\/p>\n\n\n\n
The antenna is a flex pcb with a trace, this does work but does not offer the best connection, I have noticed it is slightly worse than a normal pcb antena as some esp dev boards use.<\/p>\n\n\n\n
The HLW8012 IC is used for the energy monitoring, this IC can measure active power,voltage and current but does not calculate energy used, this has to be done in software.<\/p>\n\n\n\n
The active power value is sent to the esp via a variable frequency from the HLW8012, so when the measured active power is low the output frequency is low as well. 12w is already only 1HZ, so if we would want to measure 1.2w it would take us 10 seconds to know that..The current sense resistor used in the shelly plug is 1m\u03a9 with an accuracy of 10-20%, if you want to be somewhat accurate I should suggest calibrating the plug before putting them to use.<\/p>\n\n\n\n
The internal temperature is monitored with a NTC, this is really important for the safety of the device. when drawing large loads for longer duration the temperature can get dangerously high. I have experienced overtemperature when drawing a load of 2000W for 15 min.
The software<\/h2>\n\n\n\n Most of my code is based on the config found on the esphome devices forum, I made some adjustments to make it safer and adjust it to my liking.<\/p>\n\n\n\n
One important change I made was adding an overcurrent protection before the esp devices forum had some code that did not have that present. When a large load is connected with a bad power factor the current can go well above the rated 10A while staying below the 2300w limit. The temperature protection might not trip fast enough if the overcurrent is large enough.<\/p>\n\n\n\n
Each shelly plug has their own config that contains the name and some config and calibration data.<\/p>\n\n\n\n
substitutions:\n devicename: shelly-ps-01\n channel_1: Relay\n\n max_power: \"2200\"\n\n # Higher value gives lower watt readout\n current_res: \"0.001100\"\n # Lower value gives lower voltage readout\n voltage_div: \"1911\"\n # Power does not seem to calculated with the calibrated voltage and current vallues, Power needs its own callibration\n Power_calibration_multiplier: \"1.03888\"\n\npackages:\n base-config: !include x-shelly-ps-00-base-config.yaml\n debug-info: !include x-debug-info.yaml<\/code><\/pre>\n\n\n\nThis is the base config for the plugs containing all the sensor configuration.<\/p>\n\n\n\n
substitutions:\n #filter settings\n window_size: \"3\"\n send_every: \"1\"\n send_first_at: \"1\"\n\n max_current: \"10\"\n max_temp: \"70.0\"\n\n update_interval: \"3s\" #update interval in seconds # low update interval will cause inacurate results, measurements are based on pulses # https:\/\/tinkerman.cat\/post\/hlw8012-ic-new-sonoff-pow\n update_interval_slow: \"5s\" #update interval in seconds\n\nesphome:\n name: \"${devicename}\"\n\nesp8266:\n board: esp01_1m\n\nlogger:\n\napi:\n encryption:\n key: \"ThPfR6f+epdPwN0bx63o4+yEfejlq4DP8juJfaNr0jE=\"\n\nota:\n password: \"297e7ca2c43a39cf7c8cb62c808797b2\"\n\nwifi:\n networks:\n - ssid: !secret wifi_ssid\n password: !secret wifi_password\n #manual_ip:\n # static_ip: \"${static_ip}\"\n # gateway: 10.10.1.1\n # subnet: 255.255.255.0\n #use_address: \"${use_ip}\"\n reboot_timeout: 120min\n\ntime:\n - platform: sntp\n id: my_time\n\nbinary_sensor:\n - platform: gpio\n pin:\n number: GPIO13\n inverted: True\n name: \"${devicename}_button\"\n on_press:\n - switch.toggle: relay\n\n#red led for status\nstatus_led:\n pin:\n number: GPIO00\n inverted: True\n\n#blue light to indicate power\noutput:\n - platform: gpio\n pin: GPIO02\n inverted: true\n id: led\n\n#relay\nswitch:\n - platform: gpio\n pin: GPIO15\n id: relay\n restore_mode: RESTORE_DEFAULT_ON\n name: \"${channel_1}\"\n on_turn_on:\n - output.turn_on: led\n on_turn_off:\n - output.turn_off: led\n\nsensor:\n # NTC Temperature\n - platform: ntc\n sensor: temp_resistance_reading\n name: ${devicename} temperature\n unit_of_measurement: \"\u00b0C\"\n accuracy_decimals: 1\n icon: \"mdi:thermometer\"\n filters:\n - median:\n window_size: ${window_size}\n send_every: ${send_every}\n send_first_at: ${send_first_at}\n calibration:\n b_constant: 3350\n reference_resistance: 10kOhm\n reference_temperature: 298.15K\n on_value_range:\n - above: ${max_temp}\n then:\n - switch.turn_off: relay\n - homeassistant.service:\n service: persistent_notification.create\n data:\n title: Message from ${devicename}\n data_template:\n message: Switch turned off because temperature exceeded ${max_temp}\u00b0C\n - platform: resistance\n id: temp_resistance_reading\n sensor: temp_analog_reading\n configuration: DOWNSTREAM\n resistor: 32kOhm\n - platform: adc\n id: temp_analog_reading\n pin: A0\n update_interval: ${update_interval_slow}\n\n - platform: hlw8012\n model: BL0937\n sel_pin:\n number: GPIO12\n inverted: true\n cf_pin: GPIO05\n cf1_pin: GPIO14\n current_resistor: ${current_res}\n voltage_divider: ${voltage_div}\n current:\n name: \"${channel_1} current\"\n unit_of_measurement: \"A\"\n accuracy_decimals: 1\n icon: mdi:flash-outline\n filters:\n - median:\n window_size: ${window_size}\n send_every: ${send_every}\n send_first_at: ${send_first_at}\n on_value_range:\n - above: ${max_current}\n then:\n - switch.turn_off: relay\n - homeassistant.service:\n service: persistent_notification.create\n data:\n title: Message from ${devicename}\n data_template:\n message: Switch turned off because current exceeded ${max_current}A\n voltage:\n name: \"${channel_1} voltage\"\n unit_of_measurement: \"V\"\n icon: mdi:flash-outline\n accuracy_decimals: 0\n filters:\n - median:\n window_size: ${window_size}\n send_every: ${send_every}\n send_first_at: ${send_first_at}\n power:\n name: \"${channel_1} power\"\n id: power\n unit_of_measurement: \"W\"\n accuracy_decimals: 0\n filters:\n - multiply: ${Power_calibration_multiplier}\n - median:\n window_size: ${window_size}\n send_every: ${send_every}\n send_first_at: ${send_first_at}\n icon: mdi:flash-outline\n on_value_range:\n - above: ${max_power}\n then:\n - switch.turn_off: relay\n - homeassistant.service:\n service: persistent_notification.create\n data:\n title: Message from ${devicename}\n data_template:\n message: Switch turned off because power exceeded ${max_power}W\n change_mode_every: \"2\"\n update_interval: ${update_interval}\n\n - platform: total_daily_energy\n name: \"${channel_1} daily energy\"\n power_id: power\n filters:\n # Multiplication factor from W to kW is 0.001\n - multiply: 0.001\n unit_of_measurement: kWh<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"To monitor the power usage of many of my devices I started looking into smart plugs and came across the “Shelly plug S” advantages of this model: disadvantages: How to program? Opening it is easy, there is a screw hidden inside the ground plug, unscrew this and the front pops<\/p>\n
Continue readingShelly power plug S with esphome<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":484,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,5],"tags":[],"class_list":["post-481","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electronics","category-esphome"],"_links":{"self":[{"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/posts\/481","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/comments?post=481"}],"version-history":[{"count":2,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/posts\/481\/revisions"}],"predecessor-version":[{"id":785,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/posts\/481\/revisions\/785"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/media\/484"}],"wp:attachment":[{"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/media?parent=481"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/categories?post=481"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/labparvum.com\/index.php\/wp-json\/wp\/v2\/tags?post=481"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"\"](\"https:\/\/labparvum.com\/wp-content\/uploads\/2023\/01\/IMG20230111182041-scaled-1-1024x768.jpg\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/labparvum.com\/wp-content\/uploads\/2023\/01\/74b3dbfdbdbc0639c1a4a6cae896e889f8c84d35-1024x576.jpeg\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/labparvum.com\/wp-content\/uploads\/2023\/06\/image-11-1024x717.png\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/labparvum.com\/wp-content\/uploads\/2023\/07\/image-12.png\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/labparvum.com\/wp-content\/uploads\/2023\/07\/image-11.png\")
<\/figure>\n\n\n\n