Node mcu connection issues

ESP8266 Module ESP-12E NodeMcu


node mcu disconnects 1-50 times a day

and triggers are not always working

ive tried with multiple nodes

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how are you powering it?

ac to dc transformer 4.3v 200ma to 5V pin… should i be using a solid 5V?

if you going to the 5v pin i believe so.

i started running one at 5v to 5v pin 6 mins ago and it just became offline…

#define CAYENNE_PRINT Serial

#include “CayenneDefines.h”
#include “BlynkSimpleEsp8266.h”
#include “CayenneWiFiClient.h”

char token = “";
char ssid[] = "
char password = “______”;

void setup()
Cayenne.begin(token, ssid, password);

void loop()

is it my sketch? ^^^^^

your sketch looks good…what are your prints saying when it disconnects?

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ok fired it up connect to pc arduino ide and disconnected in seconds…

just checked my library manager and cayenne was version 1.0.0 ,so i updated to 1.0.1…
im going to re upload sketch and see what happens…

and… would the 4.3v on the vin pin even really be a problem ? the entire esp8266 runs on 3.3v, is 4.3v to low for the 3.3 voltage regulator on the ESP-12E NodeMcu ?

A typical linear regulator needs 1.2V of headroom to maintain regulation Thus you should have at least 4.5V. ESPs can draw 80mA or more, so you should really have a fairly large cap on the supply rail to keep it from resetting when transmitting. I recommend a minimum of 50uF, but others here are using 1000.

Ultimately though, you should measure your supply output when the ESP is transmitting, I bet it drops.



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yea i checked when running the 4.33v to vin it would drop to 4.1 when transmitting… i have a few 1000 uF caps but they say its 35v im not to familiar using caps yet would that help with the 4.3 volt PS?

What you need to do is measure the 3.3V supply ot the 4.3.

If ypu are droppimg to 4.1, your ESP is probably at 2.9, too low for the ESP.

That 35V is the working voltage not to exceed. You cam safely use them across the 3.3 or 5v supplies, just mind polarity.

You should really ditch the 4.33 V supply and get a 5V 1A or greater for stable regulation.




using the same 4.3 volt PS i have hooked up to a booster ( i salvaged from usb battery pack) using 4.3 PS in place of a 18650 LI battery V is constant 5.1V

just checked V at the 3.3 rail with 4.3V-4.1V and the boosted 5.1V…
with 5.1V the 3.3rail was at 3.24V and with the 4.3V-4.1V 3.3 rail was at 3.23 and with 5Vusb 3.3 was 3.28…

the new 1.0.1 libraries seems to be helping have had no disconnect issues since updating, even on the 4.3V PS
we will see if i get any text thru the night…
thanks kreggly and vapor83 for your help

ok so it disconnected twice last night… a lil better, but that was still on 4.3V …10 mins ago a broke down a 5V 1amp phone charger to use as PS i also soldered in a 1000uF cap to the 5V, lets see what happens

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im still having disconnect issues all at random times… i dont think its my hardware or PS when i use the blynk app it stays working and is more responsive , but i hate the blynk app

are you using the arduino IDE to upload your code to the nodeMCU? What cpu speed are you running?