Hi all,
I am building a UVC disinfection cabinet. I have previously posted a thread to decide on the dosage, switches, etc. I have now decided on it and its time for me to start designing the circuit. This is my first project so sorry for stupid questions, if any.
I will be using 4 x 16w UVC tubes from Philips. You can find the data sheet here. The tubes need to be connected to one ballast each. The ballasts are designed to work directly with mains power. I also need to have a timer relay and a temperature sensor to cut-off power automatically when temperature or time limit exceeds. The device should work only when the door is closed. I'm planning to use three microswitches in the same configuration as in a microwave oven.
How do I start designing the circuit?
Right now I have planned the circuit like this:
1) Wire the three microswitches in series to ensure connection only when all three switches are closed.
2) Wire these switches to the timer relay in a NO connection.
3) Temperature based relay (such as W1209) in AND logic with the timer relay
4) Relay output to ballasts
Questions I have in my mind right now:
1) How do I safely connect the mains to my device? Do I need some sort of ESD protection (I will be anyhow including a Fuse)?
2) Is it better to connect the microswitches directly to AC mains or is it better to convert the AC to LVDC and connect the switches to a relay to work only as a signalling device (if the latter is better I think I can go with lower power rated switches)?
3) What other things should I be careful with?
Thanks!
I am building a UVC disinfection cabinet. I have previously posted a thread to decide on the dosage, switches, etc. I have now decided on it and its time for me to start designing the circuit. This is my first project so sorry for stupid questions, if any.
I will be using 4 x 16w UVC tubes from Philips. You can find the data sheet here. The tubes need to be connected to one ballast each. The ballasts are designed to work directly with mains power. I also need to have a timer relay and a temperature sensor to cut-off power automatically when temperature or time limit exceeds. The device should work only when the door is closed. I'm planning to use three microswitches in the same configuration as in a microwave oven.
How do I start designing the circuit?
Right now I have planned the circuit like this:
1) Wire the three microswitches in series to ensure connection only when all three switches are closed.
2) Wire these switches to the timer relay in a NO connection.
3) Temperature based relay (such as W1209) in AND logic with the timer relay
4) Relay output to ballasts
Questions I have in my mind right now:
1) How do I safely connect the mains to my device? Do I need some sort of ESD protection (I will be anyhow including a Fuse)?
2) Is it better to connect the microswitches directly to AC mains or is it better to convert the AC to LVDC and connect the switches to a relay to work only as a signalling device (if the latter is better I think I can go with lower power rated switches)?
3) What other things should I be careful with?
Thanks!