brooksdata
@megan_b40 · Membre depuis septembre 2025
Data analyst · water and wastewater
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Traduit de English par IA ·
Nous faisons à peu près la même chose dans quelques petites stations de pompage, donc quelques remarques à ce sujet.Le Pi au milieu est un bon choix compte tenu de vos coupures. Faites-le fonctionner comme passerelle : un appareil dans Hermetry marqué « This device is a gateway », et chaque salle devient un appareil enfant dès la première fois que le Pi la signale. Node-RED récupère les messages des salles depuis Mosquitto, les conserve dans un fichier ou une petite table SQLite pendant la coupure d’Internet, puis les envoie avec leurs propres horodatages :
topic v1/gw/telemetry
{"Room 4": [{"ts": 1793000000000, "values": {"temperature": 22.1, "humidity": 51, "door_open": 0}},
{"ts": 1793000300000, "values": {"temperature": 22.0, "humidity": 51, "door_open": 1}}]}Assurez-vous que le Pi a la bonne heure (NTP au démarrage) avant d’ajouter un ts à quoi que ce soit. Un gros arriéré se vide un peu plus lentement, car les rejeux ont leur propre limite de débit dans le profil, c’est normal.La commande du chauffe-eau peut passer par le même Pi. Une commande envoyée à un appareil enfant descend vers sa passerelle sur v1/gw/rpc, donc Node-RED s’y abonne et la transmet à la bonne salle. Ou bien faites du contrôleur du chauffe-eau un appareil à part qui se connecte directement à Hermetry. Pour un chauffe-eau, je privilégierais la connexion directe, avec moins de pièces mobiles.Les topics de passerelle sont décrits dans Devices behind a gateway.
We run nearly this at a few small pump stations, so a couple of things from that.
The Pi in the middle is a good call because of your outages. Have it act as a gateway: one device in Hermetry marked « This device is a gateway », and each room becomes a child device the first time the Pi reports it. Node-RED collects the room messages from Mosquitto, keeps them in a file or a small SQLite table while the internet is down, and then sends them on with their own timestamps:
topic v1/gw/telemetry
{"Room 4": [{"ts": 1793000000000, "values": {"temperature": 22.1, "humidity": 51, "door_open": 0}},
{"ts": 1793000300000, "values": {"temperature": 22.0, "humidity": 51, "door_open": 1}}]}Make sure the Pi has the right time (NTP after boot) before you put a ts on anything. A big backlog drains a bit slower because replays have their own rate limit on the profile, that’s normal.
Geyser switching can go through the same Pi. A command sent to a child device comes down to its gateway on v1/gw/rpc, so Node-RED subscribes to that and passes it on to the right room. Or make the geyser controller its own device that connects to Hermetry directly. For a geyser I’d go direct, fewer moving parts.
Gateway topics are described in Devices behind a gateway.
Traduit de English par IA ·
Celui-là concerne le côté appareil, il attend des commandes. Je pense qu’il te faut une clé API à la place du jeton de l’appareil ; j’ai fait quelque chose de similaire avec python requests il y a quelque temps, mais je ne me souviens plus du chemin.
That one is for the device side, it waits for commands. I think you need an API key instead of the device token, I did something like this with python requests a while ago but I don’t remember the path.
Nice. Watch the 22:00 shift around the clock change in spring and autumn, our timestamps are UTC and we got a 7 hour shift once.
Grove is just a connector convention, wire it with Grove-to-female-jumper cables (or cut one cable in half). Did a classroom kit like this on ESP32s.
Digital and analog modules:
yellow SIG (the main signal: digital or analog out)
white NC or second signal (unused on most single modules)
red VCC
black GNDI2C modules use yellow = SCL, white = SDA.
Voltage is the part to check per module. The light sensor (v1.2) and loudness sensor are analog and run fine at 3.3 V, their output stays below 3.3 V, so straight into ESP32 ADC1 pins (GPIO32-39; ADC2 doesn’t work while Wi-Fi is on). The DHT11 module works at 3.3 V too, with a short cable. The Grove relay coil is 5 V: power it from the 5 V pin (VIN on the DevKit with USB), its input is happy with a 3.3 V signal.
Don’t feed any module 5 V if its output goes into an ESP32 pin, the ESP32 isn’t 5 V tolerant.
The loudness sensor gives an envelope, not audio. Sample it every 50 ms and send the max and average for the minute, e.g. {"temperature": 21, "light": 1830, "noise_avg": 312, "noise_max": 744}, so a forklift going past shows up as a peak.
What does the ERP need exactly, one total per shift or a running count?
Worth sending an error counter next to the readings, modbus.crc_errors or similar. On our sites that counter going up was always the first sign of a loose A/B wire.
Not fixed, the ESP32 can route I2C to almost any pin through its GPIO matrix. The scanner working proves your wiring is fine.
What happens is that sht4.begin() and ina219.begin() with no arguments call Wire.begin() again inside the library, and a bare Wire.begin() puts the bus back on the default pins 21 and 22. That moves I2C away from your sensors and onto your RS-485 transceiver, which explains the second symptom too.
Give the libraries the bus you already started:
Wire.begin(32, 33);
Wire.setClock(100000);
if (!sht4.begin(&Wire)) Serial.println("SHT40 not found");
if (!ina219.begin(&Wire)) Serial.println("INA219 not found");Most of the Adafruit libraries take a TwoWire*. If one does not, use Wire1 for the sensors and leave Wire alone.
On pin choice: 34 to 39 are input only, so never SDA or SCL. And stay off the strapping pins 0, 2, 12 and 15 if you can, a pull-up on 12 can stop the board from booting.
Did you turn Bluetooth off? On the Pi 3 the good UART goes to Bluetooth by default.
I’m on the data side at a water operator, so I see this argument from the people who want dashboards. Our sites run exactly this split and it’s held up for years.
The PLC does control: it scans I/O every few milliseconds whether the network is up or not, its inputs and outputs are made for 24 V field wiring and noisy cabinets, it has certified safety options, and the night-shift technician can open the ladder logic and see why a pump didn’t start. An ESP32 can do the logic, but you’d be building and certifying all of that yourself, then supporting it for 15 years.
Hermetry does monitoring and supervision: history, alarms, dashboards, operators sending a command. Even Hermetry’s own ready-made water solution keeps it that way, the pump stations’ automatic start and stop stays in the station’s controller and the cloud only switches manual mode and pumps on command. See Water site. If the internet drops, a cloud rule can’t stop a conveyor.
Where ESP32s do make sense: extra sensors the PLC doesn’t have, like vibration on a motor, temperatures in a cabinet, energy meters. Cheap, no risk, and they go straight to Hermetry.
Kevin, the cost question is the one to answer with numbers: one hour of downtime on a line versus the price of an S7-1200.
Fixed! printf version works, all seven .up keys show up and raw stopped updating. Went with Ciaran’s idea in the end because ops will add more sites, so now each site is a child with a single up key and one rule. Pump 6 had a real outage last night and the alarm opened after 5 minutes like it should.
It runs, raw updates every minute. So it’s the quoting. I always get confused by bash quotes.
Rev B is back: stitched top pour every 4 mm, antenna keep-outs cleared on all layers, antennas on opposite corners. Time to first fix went from about 3 minutes to 35 s, and LoRa SNR at the same test spot improved by 6 dB. The chart comparison was very satisfying for a data person.
Plastic box. Good thought though.
Traduit de English par IA ·
Que affiche rfkill list ? Un blocage logiciel ressemble aussi à ceci.
What does rfkill list show? A soft block looks like this too.
Traduit de English par IA ·
Côté données : avez-vous besoin d’un point toutes les 30 s pendant que la remorque est garée dans votre allée ? Pour nos fourgonnettes, nous n’envoyons des données qu’en cas de mouvement.
From the data side: do you need a point every 30 s while it’s parked in your drive? We only send on movement for our vans.