AZDelivery 3 x DS3231 RTC Real Time Clock I2C compatible with Arduino and Raspberry Pi including E-Book!

I ordered this pack of DS3231 RTC modules for a DIY project to control regular dosing of plant nutrients in my fish tank, and they’ve worked exactly as expected. The timekeeping is very accurate, and it’s reassuring that the clock retains the time even if power is interrupted. The modules are easy to wire thanks to the I2C interface, and they integrated smoothly with my microcontroller using standard libraries. Setup was straightforward, even for a custom project, and everything behaved consistently during testing. The included e-book is a helpful bonus, especially for quick reference and initial setup. Overall, these RTC modules feel well made and dependable, making them a solid choice for Arduino or Raspberry Pi projects where precise timing is important.

Working well easy to setup... I've modified one of them by removing the resistor to stop it charging the battery..great price too.

Have tested with ESP32 and these units have kept time accurately for 24 hours. Good enough for me as ESP32 rtc gains about 35 seconds per hour in deepsleep mode. The product description might lead you you believe the I2C address of the RTC can be changed, but it cannot, only the flash memory address can be changed. However, not a problem for me as 0x68 seems an uncommon one, or at least the 3 other I2C devices I have use different addresses. I am using micropython, and a good well documented library has been written by Peter Hinch called ds3231_gen.py. Google it, its on github. WARNING. Units come with a backup battery that is not rechargeable, but the units charge the backup battery by default. Either replace the CR2032 with the equivalent rechargeable type, or unsolder/cut the resistor shown in the photo. Only 4 stars because rtc address cannot be changed, and also temp sensor is +/- 3 deg C, which is pretty poor.

Purchased to build a WSPR beacon, I was initially quite pleased to find an SN (the more accurate 2ppm) variant amongst the three units shipped. Sadly, it doesn't work. The other two modules were M versions (5ppm) and they seem to work just fine. Don't forget to remove the 200 ohm resistor or else the lithium cell will get charged (not good). Edited the star rating because of superb customer service.

Running on my RPi4

Hi, I’m making a special clock for my sister and needed an RTC which was more accurate and wouldn’t loose time like the cheaper versions. This works a treat and has built in alarm function and fully interfaces with my Arduino project.

Battery not included. Header pins already on but might not suit your requirements in terms of angle. Fairly easy to use depending on skill level. Reasonable price for three.

These RTC modules are absolute rubbish. Mine lose about four or five seconds a day when they have external power and if they rely on the backup battery they lose random amounts of time from about thirty seconds to a few hours. The batteries were supplying 3.6 volts so there should have been no issues with them. On the subject of batteries, as other reviewers have said, there is a diode and resistor connecting the battery to the supply so a typical nominal 5 volt supply will try to charge the battery to 4.6 volts which will destroy the battery as well as being dangerous. Furthermore, the battery supplied is not a rechargeable one so use a battery at your peril! I would recommend removing the resistor on the charging circuit by unsoldering or physically breaking it. The supplier recommends that it is connected to the 3.3 volt pin on an Arduino which would stop the charging issue but 3.3 volts is too low for the logic levels so either does not work at all or at best is unreliable. In short,DO NOT BUY,

Dobrze, jakby wprost było napisane, że RTC nie mają załączonej baterii i trzeba ją kupić osobno.

Das RTC-Modul funktioniert einwandfrei und liefert präzise Zeitangaben. Die Installation und Integration in meine Projekte war unkompliziert, und die Module haben sich als sehr zuverlässig erwiesen. Es behält die Zeit auch bei Stromausfall dank der eingebauten Batterie, was besonders praktisch ist. Die Genauigkeit ist hervorragend und die Verbindung über I2C läuft ohne Probleme. Ideal für alle Projekte, bei denen eine genaue Zeitmessung erforderlich ist. Sehr zufrieden mit der Qualität – klare Empfehlung!

Llego como esperado. Es un RTC que funciona por I2C. La primera vez que lo usas tienes que configurar la hora y a partir de ahí lleva él solo la hora y no la pierde. Gracias a la pila, si desconectas el arduino sigue manteniendo la hora y cuando el arduino esté encendido se alimenta de la alimentación externa, preservando la pila. Estoy muy contento ya que permite hacer aplicaciones dependientes del tiempo en sitios a los que no llega Internet y no puedes sincronizarlo con la red. Por ejemplo, yo lo estoy usando en combinacion un modulo de relés para cargar unas baterías de plomo ácido una vez al mes (según recomendaciones del fabricante), el día 25. Esto no podía hacerlo con un enchufe programable, ya que la mayoría solo te permiten programar días de la semana, pero de una manera tan precisa. El reloj lleva la cuenta de: año, mes, día de mes, día de semana, minutos, segundos. Todo súper sencillo de usar a través de la librería que se puede bajar de la web de arduino o desde el gestor de librerías, que además viene con ejemplos. Un producto genial. Ya estoy buscando más aplicaciones donde usarlo.

Har inte testat men det var snabbt levererat

Nooit ontvangen; alleen een lege enveloppe. Werd daarna terug vergoed zonder problemen.