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Questions tagged [nodemcu]

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1answer
32 views

ESP32 using acs712 give wrong values

I'm trying to measure current with acs712 30A current sensor connecting to NodeMCU-32S but I'm getting wrong and unstable values. For zero current the ADC pin should read value of 2048 (esp has 12 bit ...
-1
votes
3answers
66 views

How can I increase the AMPs in a transformer less power supply

I am very new to electronics and trying to do something which I am not much aware of yet. I have a NodeMCU (based on esp8266) for which I need power supply of 5V and it required I guess more then ...
0
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1answer
33 views

Connecting nodemcu through internet

I have a NodeMCU and a website (free website domain provided by hpage.com) and I have to send and receive some data (suppose a 8-bit number) from the website to the NodeMCU via internet. The NodeMCU ...
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0answers
28 views

How to run 200 RPM motor on 5V Relay using NodeMCU?

The following circuit comprises of NodeMCU (ESP8266) which is intended to run a 200 RPM johnson motor. The circuit comprises of 5V Relay connected via Darlington pair using transistors. The circuit is ...
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0answers
50 views

Using 2N2222A transistor to switch on/off NodeMCU board

I was trying to make a battery powered project by using a NodeMCU board. To avoid desoldering some parts to achieve low consumption (Like the regulator or the UART chip) I intended to use a small ...
0
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2answers
124 views

How to switch a 12V DC (3A) Motor with a 3.3V signal? [closed]

I was previously using a 2N2222A transistor with a small dc motor and it worked fine. As soon as I used it to control the 3A motor, The circuit stopped working. Is there any way I could control the ...
0
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1answer
13 views

how to avoid harmonic on intrrupt for proximity sensor in NodeMcu

i have 5v IR proximity sensor for measuring pulse output attached in NodeMCu using intrrupt pin but it gets a random counter on the harmonic environment. it is working fine in Normal situation what ...
1
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1answer
55 views

Nodemcu responds badly to power swing

I'm using NODEMCU and SSR modules to turn on / off the lamps with WiFi. Nodemcu uses I = 80mA and V = 5v as its input current and voltage (Vin pin). It worked without any problems with a single lamp ...
0
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1answer
77 views

Running a Relay on DC

This is my diagram: I'm running a breadboard with a NodeMCU powered by a USB 5V say from my laptop. From the NodeMCU, I'm taking a 3.3v out to the VCC of the Relay and GND to GND of the relay with ...
0
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1answer
170 views

How can I attach a custom built antenna to the NodeMCU (ESP-12E)

Is there any possibility I can disable/remove the PCB antenna and replace it with a custom one, like a directional helical antenna? Can I just solder it on? I am an absolute beginner and have no real ...
1
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1answer
79 views

PT100 sensor for measuring liquid resin, fully submerged

Edited Link to Pt100 sensor (That's the best i could do) https://www.intech.co.nz/products/temperature/mrh.html Link to ESP8266 datasheet http://www.handsontec.com/pdf_learn/esp8266-V10.pdf ...
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1answer
117 views

TP4056 and li ion battery charging that never ends

I have designed a circuit with a Nodemcu ESP8266 (something similar to an arduino nano, requiring 3.3V to work) and I would like to have a backup battery to be robust to main power interruptions. So ...
0
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1answer
68 views

Programming esp8266 NodeMCU (with Arduino IDE)

I just got some esp8266 NodeMCU chips, which I want to use for IoT. I understand that these chips are programmed with Lua code. Is this correct? I found online that I can program these chips with ...
0
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2answers
63 views

relay life time [closed]

I am developing a home automation system using nodemcu esp8266. For this I want to use srd-03vdc-sl-c relay to control my appliances with nodemcu. But I am not sure that how long this system will work ...
0
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1answer
90 views

Registering IOT products across Europe based on NodeMCU

We've been designing some smart home devices and softwares in past few years and they've been sold in some countries in middle-east. Basically, they were combination of ESP, Arduino and NodeMCU boards ...
0
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2answers
57 views

Are there any reasons I shouldn’t use a nodemcu’s 3.3v pin with this component?

I have this Hydrogen Sulfide gas sensor and the datasheet says the supply voltage requires a regulated voltage with a min of 2.6v and max of 3.6v I can’t find any datasheet for the nodemcu v3 (spent ...
1
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1answer
198 views

ESP8266 - should Vin pin supply 5V?

I'm using this ESP8266 board, which has a Vin pin. This link - says specifically that Vin get a direct 5V from USB's DC. But ...
0
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1answer
258 views

Can I connect 5v 1 amp usb mobile charger to power Node MCU? [duplicate]

I am planning to power Node MCU from cable power. Can I connect mobile charger to the micro USB port? Or is it better to connect to Vin in NodeMCU?
4
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3answers
136 views

Detect drones passing through hula-hops

I host some drone races at times and I make gates with hula-hops. I fit some led stripes in there and they glow nicely. We ONLY run micro drones, F36, tinny whoop and those. And mostly indoors (...
1
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2answers
49 views

Continuity with NodeMCU on metal door

I want to have a sensor to let me know if a door is locked or not. I've placed two wires inside the lock mechanism of the door, so when the door is locked the continuity test on the multimeter make a ...
0
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1answer
71 views

Output Current of NodeMCU Digital Pin

I'm trying to power the waterproof version of the DS18b20 Temperatur Sensor via the D1 (GPIO05) Pin. I tested the setup first by using the 3.3 Volt Out Pin and by connecting a 4.7 Resistor between ...
0
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0answers
115 views

How much current does an LED in optocoupler draw?

I am planning to actuate the relay (opto-isolated) using the GPIO pins of Nodemcu. NodeMcu's datasheet says that maximum current that can be drawn out of a GPIO pin is 12 mA. Any load more that may ...
1
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1answer
76 views

Getting garbage output in serial monitor while communicating with OBD using CAN interface (MCP2515) and nodemcu

I am doing a project which involves getting vehicle speed from a car's OBD port and storing it in my database using nodemcu. I am programming nodemcu using the Arduino IDE and using this library for ...
0
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1answer
216 views

MCP23017 with NODEMCU v3 (lolin) i2c doesn't work

I want to use NodeMCU v3 with MCP23017 that has MAX6675 at the end. Everything is on circuit please see the image. MAX6675 (U3) doesn't want to work with MCP23017. First MAX6675 (U4) works perfectly ...
0
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2answers
393 views

TPL5110 doesn't work with NodeMCU

I am using a TPL5110 timer to drive my NodeMCU, in order to keep battery consumption low, but I can't let it work. I have setup the standard circuit for this timer, as below: Whenever I apply power ...
0
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4answers
138 views

NodeMCU control 12v solenoid

I am trying to control a 12v solenoid from a NodeMCU. I bought the wrong MOSFET, I've got an IRF520 (the website I bought it from said the gate threshold voltage was 3.3v, so I thought it would work, ...
0
votes
1answer
187 views

Zero-crossing signal inconsistent timing

I have an ESP-07 with NodeMCU firmware connected to a dimming module with a zero-crossing pin. The current frequency should be 50Hz, which means that the time between two zero crossing should be 10ms,...
0
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1answer
304 views

AC 230V Voltage Line Detection with sharp PC814 Switch Home Automation

I want to use home automation, so I am thinking of using INPUT to ESP8266 from PC814 bi-directional optocoupler for mains 230V physical switch. Using this scheme I don't have to modify my house ...
0
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1answer
53 views

Can this ESP wifi board's firmware be rewritten?

I'm new to all this node mcu thing. I'm searching for relay shields because they're ready and well soldered, so I can put them into my light switches with no effort. I've found this pack which ...
0
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2answers
59 views

Is the 5 V rail of an LM298 reliable?

I’m trying to build a simple robot using 4 DC motors with 2 LM298's controlled by node mcu and powered by LiPo 3s battery. Since powering the node mcu directly to the 3s LiPo(11. Iv) would be ...
0
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1answer
212 views

RobotDyn dimmer controlled by ESP 07 only results in flickers

I use a dimmer module connected to an ESP07 which has Node MCU firmware. I'm using the Z-C interrupt to skip sinusoidal pulses, however I only obtain flickering instead of dimming. The light is bulb ...
0
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2answers
69 views

Can't power controller and LEDs with chosen power supply (works in one project but not in other)

I'm currently running into a rather confusing problem... I'm trying to power a strip of 60 WS2812 Leds and an NodeMcu/ESP8266 board. The supply I chose is a 5V/4A supply. This one to be precise: ...
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0answers
92 views

How to get NodeMCU to detect an external switch closure of an unknown voltage?

I'm getting really into home automation as a side project of mine and one of the next things I would love to automate is my doorbell. Short question: If I have a switch (momentary button in the form ...
2
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3answers
438 views

Is it safe to use this relay with mains voltage?

I'm new to electronics and have recently fallen in love with it, after buying a few NodeMCUs to play around with. I currently have a load of them around my house monitoring things like temperature and ...
1
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2answers
296 views

SIM800C GSM module works via PC but not on battery

Before giving the specifications of my project, I'd like to say that I'm a total beginner in electronics but I do have a background in IT development. I also want to apologize if this question has ...
0
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1answer
50 views

Read the state from an LED in a MCP23017

I read already this 2 questions: Read state from LED in another circuit Read the state of a 12v illuminated switch from an Arduino Uno and I can read the state in a MCP23017 controlled by an ...
0
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2answers
231 views

LED Hissing issue with circuits [closed]

I have just recently designed and manufactured my very first PCB with the goal of it being a dedicated circuit to my project. I developed an ESP8266 WiFi Mood Light, but the problems I currently face ...
0
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1answer
58 views

Modifying existing PCB design of nodeMCU

I am looking for a way to modify existing nodeMCU PCB layout. I want to re-build it from scratch and add more components to it namely 0.96dpi LED display and few buttons. I want to also change the ...
0
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1answer
34 views

Relay circuit not working

I have connected my relay with a nodeMCU so that when I give commands to relay through nodeMCU the led connected to relay gets powered up. But after proper connection also it doesn't power up.
1
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2answers
217 views

esp8266 doesn't work when connected to same supply as relays

The problem: Circuit one (with Arduino Nano) did work fine. I used a separate power supply (5V wall wart) for it, because I didn't think that the on board regulator could handle 12V. Circuit two (...
0
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1answer
190 views

Powering a water pump with nodemcu

I want to use a nodemcu to water my plants. I connected a pump with a 2N2222 transistor (I know i should add a diode and a pull down on the gate). The pump is DSL370 and when it is off i measure 4.4V ...
0
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1answer
131 views

Powering NodeMCU

I am trying to power a NODEMCU board using a battery. I am using a TLV713P pin to regulate the voltage. Can I power a nodeMCU ESP 32 board using this regulated voltage by giving it to the 3v3 pin?
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0answers
26 views

BMP180 ERROR read

I have a project with an ESP8266 and a BMP 180 Following this code The first read is everything okay ..but after just 214° celsius Temperature = 22.70 Celsius Pressure = 102686 Pascal Temperature =...
0
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1answer
241 views

How to implement AES Encrypting for ESP8266 implemented on Hardware?

I need to write a basic encryption program for ESP8266. I did read the datasheet (https://www.espressif.com/sites/default/files/documentation/0a-esp8266ex_datasheet_en.pdf), and them says that existis ...
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0answers
102 views

How to connect electric door bell connection to Node MCU

I have a electric door bell ( which is powered with Double AA batteries) , when the visitor presses it , it rings , plain simple . I am thinking to remove the electric bell , and feed that input to ...
0
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1answer
742 views

I want to get data from my NodeMCU to my android application [closed]

I have a NodeMCU which is connected to 4 LEDs. If i hit a URL like 192.168.1.2/relay1on then my relay 1 gets switched on and the LED connected to it lightens up. What i want to do is i want to know ...
0
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1answer
45 views

how to use an npn as a switch between battery and motor?

I am a noob playing around with nodemcu and esp8266. I am trying to control a motor in an automated air freshener. I had been trying to power the motor with board supply but I gave that idea up when I ...
0
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1answer
969 views

Power NodeMCU with 12v to 5v 3a - 15w DC-DC Converter? [closed]

I want to power a NodeMCU and a LED Strip with 12v power supply. I don’t want to risk doing anything to the NodeMCU though so I want to convert the 12v to 5v. I have already tried a LM7805 but it gets ...
0
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1answer
580 views

nodeMCU power via battery + battery charger + booster

I need to power a nodeMCU (as far as I know it can work with 3v3 but I use some I2C modules that need 5V so .. let's power everything with 5V) I have a Li-ion battery (3.7V) I have a TP5046 based ...
0
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2answers
359 views

Best way to set up a PT100 temperature probe?

I'm looking to build a temperature sensing product and want to use a nodeMCU or similar for the MCU module (something with an analog to digital converter), an LCD a PT100 RTD like the one in this ...