Thomas shares makes

2025-06-16

Power indicator Gauge

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Openhasp device

My openHASP control panels have been eye catchers on my desk for years now. I've been using the WT32-SC01 Plus one for over a year to keep an eye on the electric power use in our house.

I designed a fancy power dial with extra arc indicators on the outside and a dynamic list of the biggest power consumers in the middle..

The idea

I had this idea of using a classic needle gauge to show the momentary power level, and add a few colored arcs to the sides to visualize these things:

  1. Momentary total power consumed by all devices
  2. In green, the solar production arcs up from the left side, if this arc matches the needle, or goes above it, all is good.
  3. In red, the power used from the grid, ideally no red line appears at all!
  4. In magenta, the power injected to the grid arcs from the right side back to the left. If its length is equal to the green arc, we're injecting all solar production.
  5. In turquoise, the solar power used for charging the car is shown arcing from the right. If there's more solar than the car can handle, a piece of magenta might pop over it at the bottom.
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Concept diagram

Here are some early screenshots of the prototypes:

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Screenshots

I added a top 4 of the biggest consumers along with progress bars representing their relative demand (including colors, car solar use is blue!). I got this idea from Sean Blanchfield's blog post on Real Time Device Power Meter for Home Assistant. I have the same view on my Home assistant dashboard using the widget mentioned on that post, and it's so nice it shouldn't be missing from my openHASP page!

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Raspberrypi running openHASP showing the consumers.

Hardware

I had WT32-SC01 board, it's a nice display with a capacitive touchscreen layer, way better than the resistive ones on my previous builds. I wanted to use the same shaped enclosure as my my other openhasp builds and found this WT32-SC01-Plus Stand With Socket enclosure on printables.com.

Appdaemon automation

This appdaemon script monitors the homeassistant entities, and will publish messages to the MQTT server to update the openHASP widget state to reflect the new values.

The appdaemon apps.yaml creates an instance of the automation and sets the parameters. Note that in the YAML snipet below there are some YAML merge keys and reference labels to reuse parts of the yaml configuration.

powerconsumers_desk:
  <<: *plate_desk
  page: 2
  <<: &powerconsumers
    module: powerconsumers
    class: PowerConsumers
    widget_start_id: 42
    widgets: 4
    sensors: &power_sensors
      sensor.sdm120_2_power: Airco
      sensor.warmtepomp_int_power: WP Weerstand
      sensor.sdm120_1_power: Warmtepomp
      sensor.tuinhuis_power: Tuinhuis
      sensor.car_solar_power_2: Laadpaal Zon
      sensor.car_grid_power_2: Laadpaal Net
      sensor.nikoplug_power: Ventilatie
      sensor.badkamer_chauffage_power: Badkamer
      sensor.kitchen_1_power: Keuken-ww
      sensor.kitchen_2_power: Keuken l
      sensor.droogkast_power: Droogkast
      sensor.wasmachine_power: Wasmachine
      sensor.veranda_power: Veranda
      sensor.fornuis_power: Kookvuur
      sensor.oven_power: Oven
      sensor.berging_power: Diepvries
    force_bar_color:
      "Laadpaal Zon": "#008b8b"

The implementation in Python:

import appdaemon.plugins.hass.hassapi as hass
from decimal import Decimal
from datetime import timedelta, datetime
import mqttapi as mqtt

default_colors = (
    (0, 2, '#6f706f'),
    (2, 10, '#0c7600'),
    (10, 50, '#537600'),
    (50, 200, '#767200'),
    (200, 500, '#765500'),
    (500, 1000, '#763500'),
    (1000, 3000, '#761400'),
    (3000, 10000, '#760000'),
)

class PowerConsumers(hass.Hass, mqtt.Mqtt):
    @property
    def force_bar_color(self):
        return self.args.get('force_bar_color',{})
    @property
    def widget_start_id(self):
        return self.args['widget_start_id']
    @property
    def widgets(self):
        return int(self.args['widgets'])

    @property
    def device_topic(self):
        return self.args['device_topic']
    @property
    def sensors(self):
        return self.args["sensors"]
    @property
    def lwt_topic(self):
        return self.args["lwt_topic"]
    @property
    def page(self):
        return self.args['page']
    @property
    def colors(self):
        return self.args.get('colors',default_colors)

    def validate_args(self):
        assert isinstance(self.colors, list) or isinstance(self.colors, tuple), f"colors must be a list or tuple"
        for value in self.colors:
            assert isinstance(value, list) or isinstance(value, tuple), f"list entry {value} should be a list or tuple"
            assert isinstance(value[0], int), f"list entry {value[0]} should be a number"
            assert isinstance(value[1], int), f"list entry {value[1]} should be a number"
            assert isinstance(value[2], str), f"list entry {value[2]} should be a string"
            assert value[2].startswith("#"), f"list entry {value[2]} should be a HTML color"
            assert len(value[2])==7, f"list entry {value[2]} should be a HTML color"

    def update(self, entity, attribute, old, new, cb_args):
        self.log(f"got update for  {entity}: {new}")
        new = int(float(new))
        self.db[entity] = new
        self.redraw()

    def redraw(self):
        print("redrawing!")
        if len(self.db) == 0:
            return
        highest = max((float(v) for v in self.db.values()))
        to_show = list(reversed(sorted(self.db.items(), key=lambda x:x[1])))
        to_show = list(to_show)[0:self.widgets]
        for i, (e, v) in enumerate(to_show):
            try:
                self.publish_entry(i, self.sensors[e], float(v)*100/highest, v)
            except ZeroDivisionError:
                pass

    def watt_to_color(self, watt):
        for start, end, color in self.colors:
            if watt > end:
                continue
            if watt < end:
                return color
        return self.colors[0][2]
    def publish_entry(self, index, name, percent, value):
        topic = f"hasp/{self.device_topic}/command/p{self.page}b{self.widget_start_id+3*index+0}.val"
        self.call_service("mqtt/publish", topic=topic, payload=f"{percent}")
        if name in self.force_bar_color.keys():
            color = self.force_bar_color[name]
        else:
            color = self.watt_to_color(value)
        self.call_service("mqtt/publish", topic=f"hasp/{self.device_topic}/command/p{self.page}b{self.widget_start_id+3*index+0}.bg_color10", payload=color)
        self.call_service("mqtt/publish", topic=f"hasp/{self.device_topic}/command/p{self.page}b{self.widget_start_id+3*index+1}.text", payload=name)
        self.call_service("mqtt/publish", topic=f"hasp/{self.device_topic}/command/p{self.page}b{self.widget_start_id+3*index+2}.text", payload=f"{value}W")

    def initialize(self):
        self.db = {}
        self.mqtt = self.get_plugin_api("MQTT")
        self.validate_args()

        for entity_name in self.sensors.keys():
            try:
                self.db[entity_name] = int(float(self.get_state(entity_name)))
            except Exception as e:
                self.log(f"can't retrieve entity {entity_name} on start")
            self.listen_state(self.update, entity_name)

        self.mqtt.listen_event(self.mqtt_message_received_event, "MQTT_MESSAGE", topic=self.lwt_topic)

    def mqtt_message_received_event(self, event, data, kwargs):
        #topic,message
        assert event == "MQTT_MESSAGE"
        self.log(f"MQTT {event} **{data}")
        topic = data.get("topic")
        payload = data.get('payload')
        if payload.startswith("{"):
            payload = json.loads(payload)
        self.redraw()

OpenHASP design

This is the list of OpenHASP widgets that make up the plate's 'page' that displays the power gauge, it consists of JSON lines, one line per widget:

{"page":2,"comment":"---------- Page 2 ----------", "bg_color":"#000000", "swipe":1}
{"id":13,"obj":"gauge","x":20,"y":20,"w":260,"h":260, "min":0,"max":10000, "val":2000, "critical_value": 10000, "scale_end_color": "#FF0000", "format": 3, "bg_color":"000000", "scale_grad_color":"#ffffff", "scale_end_color":"#ffffff", "line_color10":"#ffff44","line_width10":5,"line_opa":255, "line_color":"#ffffff","line_color60":"#ffffff","scale_grad_color":"#ffffff","scale_grad_color60":"#ffffff","scale_end_color60":"#ffffff", "bg_color10":"#ffff44", "border_color20":"#000000"}
{"page":2,"id":17,"obj":"arc","x":6,"y":10,"w":270,"h":290,"min":0,"max":10000,"val":2000,"border_side":0,"type":0,"rotation":0,"start_angle":135,"end_angle":45,"adjustable":"false","line_width":21,"line_width10":10,"line_color10":"#00ff00","line_color20":"#ffffff","line_opa30":"0","bg_opa":0,"pad_top20":5,"pad_bottom20":5,"pad_left20":5,"pad_right20":5,"pad_bottom":5,"pad_left":5,"pad_right":5}
{"page":2,"id":20,"obj":"arc","x":16,"y":10,"w":270,"h":270,"min":0,"max":10000,"val":3000,"border_side":0,"type":0,"rotation":0,"start_angle":135,"end_angle":45,"adjustable":"false","line_width":21,"line_width10":10,"line_color10":"#ffff00","line_color20":"#ffffff","line_opa30":"0","bg_opa":0,"pad_top20":5,"pad_bottom20":5,"pad_left20":5,"pad_right20":5,"pad_bottom":5,"pad_left":5,"pad_right":5}
{"page":2,"id":18,"obj":"arc","x":16,"y":10,"w":270,"h":270,"min":0,"max":10000,"val":500,"border_side":0,"type":0,"rotation":0,"start_angle":135,"end_angle":45,"adjustable":"false","line_width":21,"line_width10":10,"line_color10":"#ff0000","line_color20":"#ffffff","line_opa30":"0","bg_opa":0,"pad_top20":5,"pad_bottom20":5,"pad_left20":5,"pad_right20":5,"pad_bottom":5,"pad_left":5,"pad_right":5}
{"page":2,"id":25,"obj":"arc","x":16,"y":10,"w":270,"h":270,"min":0,"max":10000,"val":0,"border_side":0,"type":2,"rotation":0,"start_angle":135,"end_angle":45,"adjustable":"false","line_width":21,"line_width10":10,"line_color10":"#008b8b","line_color20":"#ffffff","line_opa30":"0","bg_opa":0,"pad_top20":5,"pad_bottom20":5,"pad_left20":5,"pad_right20":5,"pad_bottom":5,"pad_left":5,"pad_right":5}
{"page":2,"id":19,"obj":"arc","x":16,"y":10,"w":270,"h":270,"min":0,"max":10000,"val":0,"border_side":0,"type":2,"rotation":0,"start_angle":135,"end_angle":45,"adjustable":"false","line_width":21,"line_width10":10,"line_color10":"#ff00ff","line_color20":"#ffffff","line_opa30":"0","bg_opa":0,"pad_top20":5,"pad_bottom20":5,"pad_left20":5,"pad_right20":5,"pad_bottom":5,"pad_left":5,"pad_right":5}
{"obj":"label","id":16,"x":0,"y":220,"w":300,"h":24,"text":"\uF40B kW","align":"center","text_color":"#ffffff","value_font":22,"bg_color":"#000000","bg_opa": "0","radius":0,"border_side":0}
{"page":2,"id":60,"obj":"obj","x":75,"y":75,"w":150,"h":150,"radius":1000,"border_color":"#000000","bg_opa10":188,"bg_color10":"#000000"}

{"obj":"bar","id":42,"x":80,"y":110,"w":140,"h":4,   "border_width":0,"val":70,"bg_color10":"#a83232", "bg_color":"#111111","radius10":5,"radius00":5}
{"obj":"label","id":43,"x":80,"y":89,"w":139,"h":20,"bg_color":"#000000","border_color":"#C7BAA7","border_width":0,"text":"Warmtepomp hitte","text_font":16,"align":"left"}
{"obj":"label","id":44,"x":80,"y":90,"w":140,"h":20,"bg_color":"#000000","border_color":"#C7BAA7","border_width":0,"text":"10W","text_font":16,"align":"right"}

{"obj":"bar","id":45,"x":80,"y":140,"w":140,"h":4,   "border_width":0,"val":50,"bg_color10":"#3ea832", "bg_color":"#111111","radius10":5,"radius00":5}
{"obj":"label","id":46,"x":80,"y":120,"w":139,"h":20,"bg_color":"#111111","border_color":"#C7BAA7","border_width":0,"text":"Thuinhuis","text_font":16,"align":"left"}
{"obj":"label","id":47,"x":80,"y":120,"w":140,"h":20,"bg_color":"#000000","border_color":"#C7BAA7","border_width":0,"text":"20W","text_font":16,"align":"right"}

{"obj":"bar","id":48,"x":80,"y":170,"w":150,"h":4,   "border_width":0,"val":20,"bg_color10":"#a8a432", "bg_color":"#111111","radius10":5,"radius00":5}
{"obj":"label","id":49,"x":80,"y":150,"w":139,"h":20,"bg_color":"#111111","border_color":"#C7BAA7","border_width":0,"text":"Keuken","text_font":16,"align":"left"}
{"obj":"label","id":50,"x":80,"y":150,"w":140,"h":20,"bg_color":"#000000","border_color":"#C7BAA7","border_width":0,"text":"30W","text_font":16,"align":"right"}

{"obj":"bar","id":51,"x":80,"y":200,"w":150,"h":4,   "border_width":0,"val":20,"bg_color10":"#a8a432", "bg_color":"#111111","radius10":5,"radius00":5}
{"obj":"label","id":52,"x":80,"y":180,"w":139,"h":20,"bg_color":"#111111","border_color":"#C7BAA7","border_width":0,"text":"Keuken","text_font":16,"align":"left"}
{"obj":"label","id":53,"x":80,"y":180,"w":140,"h":20,"bg_color":"#000000","border_color":"#C7BAA7","border_width":0,"text":"30W","text_font":16,"align":"right"}

{"page":2,"id":61,"obj":"obj","x":0,"y":0,"w":320,"h":420,"border_opa":0, "border_color":"#000000","bg_opa10":0,"bg_color10":"#ffffff", "swipe":1}

{"page":0,"comment":"---------- All pages ----------","swipe":1}
{"page":0,"obj":"btn","id":1,"x":0,  "y":420,"w":80,"h":50,"opacity":255,"text":"\uE75A","radius":0,"border_width":"0","bg_color":"#444444","text_font":24,"action":"p1","text_color":"#ffffff"}
{"page":0,"obj":"btn","id":2,"x":80,"y":420,"w":80,"h":50,"opacity":255,"text":"\uF40B","radius":0,"border_width":"0","bg_color":"#44444","text_font":24,"text_color":"#ffffff", "action":"p2"}
{"page":0,"obj":"btn","id":3,"x":160,"y":420,"w":80,"h":50,"opacity":255,"text":"\uE210","radius":0,"border_width":"0","bg_color":"#444444","text_font":24,"text_color":"#ffffff","action":"p3"}
{"page":0,"obj":"btn","id":5,"x":240,"y":420,"w":80,"h":50,"opacity":255,"text":"\uE2DA","radius":0,"border_width":"0","bg_color":"#444444","text_font":24,"text_color":"#ffffff","action":"p4"}

{"page":0, "obj":"label","id":4,"x":0,"y":0,"w":300,"h":30,"text":"?\uE2DA","value_font":22,"bg_color":"#000000", "text_color":"#ffffff", "bg_opa": 0,"radius":0,"border_side":0, "align":"right"}

Home assistant dashboard equivalent

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Home assistant power visualisation using bar-card and custom template card.

Check out my article on the modbus current clamps to see how I measure the power on several of the breaker circuits of my house and how to add a similar bar card visualisation.

Chores

I also added a page to the openHASP displaying the periodical house chores tracked in Grocy. This deserves its own article actually!

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chores


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