Vermes
Advanced Member level 4
Presented here popular time programmer has the following advantages:
- simplicity of entering the settings
- flexibility of combinations
- reliability for several years
After disassembling, you can identify two blocks: executive and power block, or transformerless power supply, a relay and charging system of mounted maintain battery and control of the relays.
On the other side, here is a control system connected by three cables:
It is easy to identify which signals are connected by those cables. First and third is the control system 1,5V supply, and the second is an output which controls the relay.
Transformerless power supply stabilied by a Zener diode, then a diode and resistor was placed on the PCB. There is also a simple charging system of maintain battery (the battery – an accumulator in housing AAA). Triac BTA 16 on a small heat sink, controlled by MOC 3041 and transistor, was added instead of the relay. In addition, you can use an indicator of the operation of the system.
Link to original thread (useful attachment) - Przeróbka programatora czasowego