silas greenback
New Member
Hi So, I have designed a circuit to send two switching signals down one wire, Basically i have a heating controller that can control both the central heating and hot water, The Cable its on is only 4 core including Earth, so a live and negative, a switch return out and insulated earth.
Because i can not easily replace the cable, i can currently only use the central heating portion of the control, because i need an extra core for the hot water
I have come up with this circuit
When SW1 only the positive part of the part rectified signal is sent and closes RLY1, when SW2 is closed only the negative part of the signal is sent and RLY2 is closed, when both switches are closed, the full wave is sent, so both relays close
Each Relay needs a capacitor to hold it closed during the half of the wave thats missing, i have built this as a test circuit running on 12 volts 50hz and 1000uF is ideal with only .7 volt ripple
I now would like to make this circuit work at 240 volts ac 50hz, the relay coils use 4.5mA and are 28k ohms, does anyone know how to work out the value of the capacitor for 240 volts?
**broken link removed**
Because i can not easily replace the cable, i can currently only use the central heating portion of the control, because i need an extra core for the hot water
I have come up with this circuit
When SW1 only the positive part of the part rectified signal is sent and closes RLY1, when SW2 is closed only the negative part of the signal is sent and RLY2 is closed, when both switches are closed, the full wave is sent, so both relays close
Each Relay needs a capacitor to hold it closed during the half of the wave thats missing, i have built this as a test circuit running on 12 volts 50hz and 1000uF is ideal with only .7 volt ripple
I now would like to make this circuit work at 240 volts ac 50hz, the relay coils use 4.5mA and are 28k ohms, does anyone know how to work out the value of the capacitor for 240 volts?
**broken link removed**