Largest trace clearance requirement for any mains voltage is just under half an inch for uninsulated free air conductors. If you have something mains powered and you can't get that, you're doing something wrong. Even if you're working with thermionic valves, you won't have anything powered from Euro peak rectified voltage in a ballistic missile.
You give the example of clearance between 24VDC and 162VAC. The peak voltage difference for spacing will need to be 186V (not 138V) as the negative portion of the AC now has a greater potential to the positive DC.
For that particular example you're right but it will be different peak voltage difference on the negative AC swing but it will not matter both for internal and permanently coated external conductors (columns B1 and B4 in the 2221 table). It does matter for column B2 where you have uncoated conductors (landing pads) but if you rectify to DC it will always be the same value.
Hi, Mr.Zach, I have curious about the usb-c d1+, d1-, d2+ and d2-, If I have two for example atmega328p, does this usb-c can program one of the atmega using d1+-, and program to another atmega using d2+- separately, which means I can program two atmega when I plug the usb with different polarity. I know all people just connect them together, but I wonder if my idea will works or not? If my idea works, then may I need two usb to uart ICs like ft232RL or not?
Yeah I understand, always have to play with the clicks to get it to work reliably when I'm using an odd-shaped blanket directive (which is not very often).
In terms of the clearances required at high voltages no there is not a difference. In terms of capacitive impedance between two conductors, yes there is a ~20% difference.
Largest trace clearance requirement for any mains voltage is just under half an inch for uninsulated free air conductors. If you have something mains powered and you can't get that, you're doing something wrong. Even if you're working with thermionic valves, you won't have anything powered from Euro peak rectified voltage in a ballistic missile.
You give the example of clearance between 24VDC and 162VAC. The peak voltage difference for spacing will need to be 186V (not 138V) as the negative portion of the AC now has a greater potential to the positive DC.
For that particular example you're right but it will be different peak voltage difference on the negative AC swing but it will not matter both for internal and permanently coated external conductors (columns B1 and B4 in the 2221 table). It does matter for column B2 where you have uncoated conductors (landing pads) but if you rectify to DC it will always be the same value.
Hi, Mr.Zach, I have curious about the usb-c d1+, d1-, d2+ and d2-,
If I have two for example atmega328p, does this usb-c can program one of the atmega using d1+-, and program to another atmega using d2+- separately, which means I can program two atmega when I plug the usb with different polarity.
I know all people just connect them together, but I wonder if my idea will works or not? If my idea works, then may I need two usb to uart ICs like ft232RL or not?
How did you add a vertices to the blanket? The usual pressing “Insert” method doesn’t work reliably.
Yeah I understand, always have to play with the clicks to get it to work reliably when I'm using an odd-shaped blanket directive (which is not very often).
Hi Zach would there be any significant differences when using 50Hz AC supply vs 60Hz when designing PCBs?
No
In terms of the clearances required at high voltages no there is not a difference. In terms of capacitive impedance between two conductors, yes there is a ~20% difference.
@@Zachariah-Peterson Thanks for the detailed explanation Zach!
Of course - 10Hz