Hi!
I have six magnetic sensors that each operates three LR44 (buttons cell 3 x 1.5V)
http://www.china-rl.com/products/list_info_725.html
Powered at 4.5V sensor shows me the following protocols:
debug [pimatic-homeduino] switch8: {systemcode 10, programcode: 'F7', states: false}
debug [pimatic-homeduino] switch6: {systemcode 10, programcode 26, states: true}
We found that if the sensor power the 3V (two AAA batteries or AA) shows me and other protocols.
debug [pimatic-homeduino] contact2: {id: 768703, contact: false}
debug [pimatic-homeduino] switch8: {systemcode 10, programcode 'F7', states: false}
debug [pimatic-homeduino] switch7: {unit: 5, id: 0, state: false}
debug [pimatic-homeduino] switch6: {systemcode 10, programcode: 28, states: true}
debug [pimatic-homeduino] switch5: {id: 768703, unit 0, all: true, states: true}
debug [pimatic-homeduino] switch4: {unit 10, id: 7 states: false}
debug [pimatic-homeduino] switch3: {houseCode 10, unitCode: 7 states: true}
debug [pimatic-homeduino] Switch2: {houseCode 10, unitCode: 7 states: false}
It works very well at 3v, driving distance is not modified.
As such we fed all sensors at 3v to use the protocol “contact2”