Modifications made by Licensee (see section 3.4.b in )

Rev 1 (Never produced)
2 stackable boards, with primary (AC) side on botton board and secondry side (DC with arduino and radio) on top board. Using HLK-PM01 as AC/DC converter. 
-Converter 240v/120v AC to 5v DC (HLK-PM01)
-Arduino Pro Mini
-NRF24L01+ 

Rev 2 (Never produced)
Complete new PCB layout, one board with primary side (AC) to left. 
New security components (0,3A fuse, thremal fuse, Varistor). 
Included MYSX 1.4 connector (https://www.mysensors.org/hardware/mysx) 

Rev 3 
- AC and DC seperation (<3.3mm, meaning you can only use it inside Pollution lev I)
- Larger creepage/clearance between AC ciriut (Minimum < 2.5mm on AC side, allowed to use in Pollution lev I)
- Safety recommendations: Always use this revision inside a sealed case or in an enviroment where contamination or moisture condensation not occurs. Please update to latest rev for best safety!
- Larger distance/gaps for fuse and thermal fuse.
- Larger throughholes in PCB for fuse and thermalfuse
- Changed location (moved down and rotate 45dgr) for varistor and screw terminal block.
- Added a safety warning on silk
- Added logo on silk
- Added temp (dallas) for node temperature.
- Added small screwholes in corners to easy be able to remove them.
- Larger distance between AC and DC side (to avoid creepage)
### Rev 3 can not be considered safe due to small AC-DC seperation - please use latest rev or only inside sealed case.

Rev 3.1
-Larger AC and DC seperation (<3.3mm, meaning you can only use it inside Pollution lev I)
-Larger creepage/clearance between AC ciriut (Minimum 2.5mm on AC side, allowed to use in Pollution lev II)
-Safety recommendations: Always use this revision inside a sealed case or in an enviroment where contamination or moisture condensation not occurs.
-Added label with license on board.
-Moved voltage regulator to increase distance to AC side
-Removed high voltate on silk screen
-Added holes between AC ciriut to decreace creepage
-Added lines on silkscreen to mark AC and DC gap.

Rev 4.1
- Complete redesign of traces to improve size and stability.
- Nrf24l01+ now on the bottom side to make more room (with hope not RF disturbace from HLK or AC traces).
- Added silkmask with AC-DC seperation (Rev 4.1 > 5mm)
- AC clearance 2.5mm minimum
- Changed one AC trace from botton to top to increace creepage and changed milling
- MysX 2.3 + Analog IO	
- Safety recommendations: This PCB meets the criteria of pollution level II (2,5mm (Basic) AC seperation and 5mm (Reinforced) AC-DC sepertion) and can be used "where only non-conductive contamination occurs. However, occasional temporary conductivity must be expected as a result of moisture condensation." Always use a sealed case to avoid contamination. Always read disclaimer.txt before using this PCB.