README.md
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ESPurna Boards

ESPurna-H

The ESPurna-H board is a custom ESP8266-based smart wall switch. It's singularity is that it's meant to be embedded into the wall behind a standard wall switch, replacing the mechanic switch with a wifi-enabled smart switch.

The board is based on the HLW8012 power monitor IC, the same the Sonoff POW uses.

It features:


SPDT 10A relay with NO and NC connections brought out
Connections for external button and notification LED
HLW8012 chip for power monitoring
50x50mm low profile form factor to fit in the wall switch hole










Bill of materials




  
Item
  
Location(s)
  
Buy
  
Required
  
Optional H
  
CPU units
  
Total
  
Total H




  
Tinkerman ESPurna-H PCB
  

  
<![CDATA[]]>OSH Park<![CDATA[]]>
  
1
  

  
6.50€ 3
  
6.50€
  



  
Ai-Thinker ESP12F
  
ESP-12
  
<![CDATA[]]>Aliexpress<![CDATA[]]> / <![CDATA[]]>Ebay<![CDATA[]]>
  
1
  

  
2.10€ 5
  
2.10€
  



  
Hi-Link HLK-PM01
  
HLK-PM01
  
<![CDATA[]]>Aliexpress<![CDATA[]]> / <![CDATA[]]>Ebay<![CDATA[]]>
  
1
  

  
2.16€ 5
  
2.16€
  



  
Songle SRD-05VDC-SL-C
  

  
<![CDATA[]]>Aliexpress<![CDATA[]]> / <![CDATA[]]>Ebay<![CDATA[]]>
  
1
  

  
0.39€ 3
  
0.39€
  



  
AMS1117-3.3
  
IC1
  
<![CDATA[]]>Aliexpress<![CDATA[]]> / <![CDATA[]]>Ebay<![CDATA[]]>
  
1
  

  
0.03€ 50
  
0.03€
  



  
HLW8012
  
IC4
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  

  
1
  
0.72€ 20
  

  
0.72€


  
SF70E 73C thermal fuse
  
F1
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
1.20€ 5
  
1.20€
  



  
Fuse holder
  
FUSE
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.06€ 100
  
0.06€
  



  
500mA 250V fuse
  
FUSE
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.05€ 100
  
0.05€
  



  
Varistor 270V
  
VARISTOR
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.18€ 20
  
0.18€
  



  
Push button
  
RESET
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.02€ 100
  
0.02€
  



  
1N4148 SMD Diode
  
D3
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.04€ 100
  
0.04€
  



  
2N7002 SOT-223 N-Mosfet
  
Q2, Q3, Q4
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
2
  
1
  
0.05€ 50
  
0.10€
  
0.05€


  
10uF 0805 tantalum capacitor
  
C11, C12
  

  
2
  

  
0.01€ 100
  
0.02€
  



  
100nF 0805 ceramic capacitor
  
C21, C22, C43, C45
  

  
2
  
2
  
0.01€ 100
  
0.02€
  
0.02€


  
33nF 0805 ceramic capacitor
  
C41, C42
  

  

  
2
  
0.01€ 100
  

  
0.02€


  
1uF 0805 ceramic capacitor
  
C44
  

  

  
1
  
0.01€ 100
  

  
0.01€


  
0.001 2512 Ohm resistor
  
R41
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  

  
1
  
0.03€ 10
  

  
0.03€


  
0 Ohm 1206 resistor
  
R42
  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  

  
1
  
0.01€ 500
  

  
0.01€


  
22Ohm 0805 resistor
  
R27
  

  
1
  

  
0.01€ 100
  
0.01€
  



  
300Ohm 0805 resistor
  
R28
  

  
1
  

  
0.01€ 100
  
0.01€
  



  
1KOhm 0805 resistor
  
R31, R43, R44, R50
  

  
1
  
3
  
0.01€ 100
  
0.01€
  
0.03€


  
10KOhm 0805 resistor
  
R21, R22, R23, R24,R25, R26, R32, R45,R47, R49
  

  
7
  
3
  
0.01€ 100
  
0.07€
  
0.03€


  
15KOhm 0805 resistor
  
R46, R48
  

  

  
2
  
0.01€ 100
  

  
0.02€


  
470KOhm 0805 resistor
  
R51, R52, R53, R54,R55
  

  

  
5
  
0.01€ 100
  

  
0.05€


  
2 positions 5mm screw terminal
  

  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.06€ 100
  
0.06€
  



  
3 positions 5mm screw terminal
  

  
<![CDATA[]]>Aliexpress<![CDATA[]]>
  
1
  

  
0.07€ 100
  
0.07€
  



  
5x2 position male header
  

  

  
1
  

  
0.01€ 100
  
0.01€
  



  
Total
  

  

  

  

  

  
13.11€
  
0.97€





(H) Optional, only required for power monitor.
(units) Minimum quantity for the stated price.
Prices are based on the cheapest option, usually Aliexpress.
Check the schematic (image or eagle file) for relation between parts and values.


Firmware

NOTE: PLEASE NOTE THAT IT IS A REQUIREMENT OF THE HLW8012 POWER MONITOR CHIP TO TIE THE POWER LINE TO THE CIRCUIT GROUND. THIS MEANS THAT YOU SHOULD NEVER EVER CONNECT THE BOARD GROUND TO YOUR COMPUTER WHILE CONNECTED TO MAINS. NEVER EVER FLASH THE BOARD WHILE CONNECTED TO MAINS!!

The ESPurna board is named after the <![CDATA[]]>ESPurna firmware<![CDATA[]]> which features:


Support for multiple ESP8266-based boards (check list)
Support for up to 5 different network configurations
Support for different types of switches and different options (pulses, synchronization,..)
MQTT enabled
Alexa integration using the FauxmoESP Library
Domoticz integration via MQTT
Home Assistant integration via MQTT
Support for different sensors (DHT22, DS18B20, HLW8012, current sensors, analog sensors,...)
Fast asynchronous HTTP Server
Backup and restore settings option
Upgrade firmware from the web interface
REST API (enable/disable from web interface)
Over-The-Air (OTA) updates
... and much more


Open Hardware

Hardware designs (schematics and CAD) files are licensed under the <![CDATA[]]>Creative Commons Attribution-ShareAlike 3.0 Unported License<![CDATA[]]> and follow the terms of the <![CDATA[]]>OSHW (Open-source hardware) Statement of Principles 1.0.<![CDATA[]]>

Disclaimer

THIS PRODUCT IS TARGETED TO EXPERIENCED USERS AT THEIR OWN RISK. THIS PRODUCT IS MEANT TO BE USED PLUGGED TO MAINS AND IT REQUIRES A DEEP UNDERSTANDING OF THE PERILS OF HIGH VOLTAGE ON HUMAN LIFE.

TO THE FULLEST EXTENT PERMISSIBLE BY THE APPLICABLE LAW, I HEREBY DISCLAIM ANY AND ALL RESPONSIBILITY, RISK, LIABILITY AND DAMAGES ARISING OUT OF DEATH OR PERSONAL INJURY RESULTING FROM ASSEMBLY OR OPERATION OF THIS PRODUCT.