Now I designed one products for the PLC system.
The Human interface includes one dip switch. when I perform the ESD air discharge(6K 20 times, one error, 8K 10 times one error), the noise will through the dip swtich into the system, the affect is the system another unit will be reset. Now I don't have any good ideas for it. What Can I do?
the best solution for ESD is to connect the TVS for all the signals
as you are saying you have only one interface test point route all the signals through TVS with respect to ground, you can see the improvement. if for SMD you can even use SMBJ. try to use the SMBJ of double the voltage where you are using(for ex if you are using for 5v signal use SMBJ of atlest 10v rated)