I need to design a circuit to switch on a warning lamp or sound a hooter when a door is opened and the reed switch is activated by the magnet. I have herewith attached the circuit diagram of the test setup. My problem is that the reed switch fails within a few (3 or 4) operations though the current measured is in very small units.
Kindly advise me how to go about it to solve the problem.
Can you provide a data sheet for the reed switch? Also, I don't understand what you are doing? You have DC coming in and the switch is switching the DC into a full wave bridge rectifier? Is the switch N/O or N/C?
I assume 110VAC input was intended?
How small a current is 'very small'? The inrush current to charge the cap across the SMPS (wrong polarity shown on SMPS, btw) and the reservoir cap within it may well be enough to weld the contacts of the reed switch. What are the AC and DC current ratings of the switch contacts?
I assume 110VAC input was intended?
How small a current is 'very small'? The inrush current to charge the cap across the SMPS (wrong polarity shown on SMPS, btw) and the reservoir cap within it may well be enough to weld the contacts of the reed switch. What are the AC and DC current ratings of the switch contacts?
Yes alec it was intended to be 110VAC. Normally is it wrong to wire a reed switch in series with a an SMPS ? Can I alternatively put the reed switch on the`secovdary side ?
Here is a set of specs from a manufacturer. https://www.actsensors.com/reed_switch.htm Note that they are all over the map. The SMPS can probably be considered an inductive load and therefore surge suppression is mandatory such as a ZNR across the contacts. Specs of the switch would be useful.
The secondary side is also permissable if the ratings aren't exceeded.
Yes alec it was intended to be 110VAC. Normally is it wrong to wire a reed switch in series with a an SMPS ? Can I alternatively put the reed switch on the`secovdary side ?