Questions tagged [clearance]
Clearance denotes the shortest distance between two conductive parts as measured through the air.
64 questions
13
votes
5answers
21k views
Cleaning PCBs… using water?
我发现这个视频,技术人员有很多of experience seems to clean his PCBs using water, and then he just puts it in the sun so it can dry. I was just amazed to see the circuit keeps ...
12
votes
5answers
35k views
How do I disable clearance check for a layer or for only some certain elements?
I'm designing a PCB in Altium Designer. There is a very large heat sink in my project. When I put it on the PCB, there will be plenty of empty space under it where I can put other small components. I ...
10
votes
3answers
28k views
How to change polygon clearance in Altium
In Altium, when I draw a polygon, it automatically leaves a gap around copper of a different net. However, my Vin net is high voltage, and needs to have a 1mm clearance. Therefore, If I draw a Vin ...
9
votes
1answer
16k views
Clearance rules for outer/inner layers?
I found some information about general creepage and clearance distances here but it doesn't mention what is OK for inner layers, which are insulated and not subject to contamination the way outer ...
8
votes
2answers
2k views
Will a cut or a slot in a PCB change clearance or creepage?
Does a cut or a slot in a printed circuit board increase clearance, creepage or both? Some say it will increase clearance, but I don't think clearance will change because, even with a cut in the PCB, ...
6
votes
1answer
5k views
PCB trace clearance in 220V circuit
This is a pcb layout where I am converting 220V rms to a DC voltage (for microcontroller). The pcb has severe size constraints. This is one design I could come up with: Circuit explanation: Consider ...
6
votes
2answers
179 views
Maintaining clearances in HV MOSFET footprints
I'm thinking of making a prototype PCB which would use a bridge rectified AC, which will end up with peaks around 350V in my area (+/- some smoothing). It's a through-hole design and the circuit will ...
6
votes
2answers
443 views
High Voltage Capacitor Lead Clearance
I am designing a high voltage board, 10,000 VDC. I wish to use a suitably rated capacitor such as theDHR4E4A102K2BB. When I have been studying the ...
6
votes
1answer
293 views
Barrier and slot within reduced area on a PCB
Imagine this situation in a little area of your PCB: According to the worst case and used material, I need a creepage distance = 30mm. According some tables, clearance must be 30mm. First Red banana ...
5
votes
3answers
578 views
Why does increasing altitude (low air pressure) results in lower resistivity/ breakdown voltage?
I got this question because the creepage and clearance distances need to be adjusted for altitude. The higher the altitude, the higher the distances should be. It seems to me however that the contrary ...
5
votes
2answers
4k views
How is clearance affected by altitude (air pressure)?
Let's say you have a high-voltage circuit (or any voltage really) and you want to provide appropriate clearance distance for the PCB, connector pins, etc. (Above image from link) There are standards ...
5
votes
1answer
463 views
How does a fuse affect creepage reqirements?
I am designing a mains-powered device that has to comply with IEC 60079-15 (Non-incedive industrial eqipment). Creepage distances in this standard are inherited from IEC 60664, pollution degree 3. For ...
5
votes
1answer
126 views
TO-277A Package Rated for 1000V
I'm looking at using the following part, S4PM: Datasheet The part has a Vrrm of 1000V. The mounting pad layout shows a separation of 0.81mm between cathode and anode. This is well below IPC2221B ...
5
votes
1answer
2k views
Ethernet LED & Diffpair Clearance
How do you maintain creepage distance between diff pairs and the LED terminals on an Ethernet connector? My understanding is that based on EN60950, for 250V IT equipment, the air clearance is 2mm and ...
5
votes
2answers
3k views
High Voltage PCB
I am building a test probe PCB to test 75-115V. What is the minimum distance between traces that I should adhere to when building my PCB? I will have ground, 3v and 115V traces running next to each ...
