Bed wetting alarm
Posted: Sun Jun 12, 2016 12:50 am
Hi,
Nice circuit aprart from the mains power supply. A unit like this that is by design in contact with a wet person should ideally not be powered from the mains, and if it is the power supply MUST be a low leakage medical grade type. The maximum leakage current for this type of application is 300uA. see www.excelsys.com/wp-content/up...
A power supply can have high leakage even without a fault. First (and possibly last) thing you know is when the alarm goes off and you reach for the (grounded) bedside lamp........
Best method is stick with battery power.
G8RPI
Nice circuit aprart from the mains power supply. A unit like this that is by design in contact with a wet person should ideally not be powered from the mains, and if it is the power supply MUST be a low leakage medical grade type. The maximum leakage current for this type of application is 300uA. see www.excelsys.com/wp-content/up...
A power supply can have high leakage even without a fault. First (and possibly last) thing you know is when the alarm goes off and you reach for the (grounded) bedside lamp........
Best method is stick with battery power.
G8RPI