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stripboard

A stripboard track's current carrying capacity can be increased by using tracks in parallel, tinning it with solder or soldering tinned copper wire onto it, etc. but what is the current carrying capacity of a one track as it comes and for how long, without causing unwanted change in the circuits reliability?

There is some info about temperature rise with current in a pdf at Printed Circuit Board Track or Trace Current Carrying Capacity per mil std 275 and an image at Extract from VEROBOARD MANUAL 1960 which implies maybe 0.5 to 1.0 A max but they're not very specific.

Rob Kam
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  • That manual tells you the current limit vs allowable temperature rise. What constitutes allowable is up to the user. – Tom Carpenter Mar 20 '16 at 16:42
  • Also depends on ambient temperature and air flow rate. What is your definition of "damage"? Allowable safe temperature rise also depends on the substrate material. – soosai steven Mar 20 '16 at 18:00
  • Changed "damage" to "causing unwanted change in the circuits reliability". – Rob Kam Mar 20 '16 at 20:36

3 Answers3

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The track of a stripboard is 2mm (78 mil) wide. The holes drilled into them are 0.8mm (31 mil) in diameter, leaving a total (0.6mm [23 mil] on each side of the hole) of 1.2mm (47 mil) for a maximum usable current path. Thickness of Veroboard/Stripboard at 1 ounce per square foot is 35 microns (1.37 mil) thick.

Assuming that you have an ambient of 25 degrees C (77F) and can tolerate of up to 50 degrees C (90F) more, then fed into a pcb track width calculator it spits out:

5.4 Ampere

http://www.desmith.net/NMdS/Electronics/TraceWidth.html

captcha
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    And that's before you tin it up a bit. Glob on solder for improved current capacity. – Passerby Mar 21 '16 at 05:47
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    And that's a lower bound estimate. I think that it's a lot higher. Don't forget that the thin bit is only localised immediately around the hole. Between holes it's 2mm wide and that will act as a substantial heat sink if you compare the two thermal masses of copper. I estimate there is 6 times more copper between holes longitudinally than laterally either side of them. A finite element analysis might be interesting to see what the real maximum is... – Paul Uszak Sep 06 '16 at 14:50
  • or just calculate the area of copper in (say) a 10mm length, then assume a track of equivalent width with no holes. It probably isn't perfect but close enough. Confirm by experiment. – danmcb Jun 19 '23 at 05:56
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I have had about 10Amps going through my tracks in the past and for sure not for longer than 15 mins at a time but never seemed to have had a problem, never really gave it much thought, just did it it worked and thats that, guess if it had burned up I would have not done it again?

Major Disaster
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There is no way we, the users, can depend upon Veroboard today, as each manufacturer tries to skimp. The last time I checked, the thickness of the track was 0.00086" and I was running into trouble with a total current of 37mA producing a volts drop!! The width around the holes is the limiting factor. To guarantee a good earth line, solder all your components in place and then solder a piece of wire along the strip ... that's belt & braces earthing and/or return to source. When building prototypes, never, ever trust anything, test each and every component for correct parameter. KNOW what you are dealing with, never trust, never assume. I've actually fitted a clamp on a car battery and clamped it, only to find a volts drop between the clamp and the terminal post! Cleanliness is essential. When soldering, count to three seconds before you let go of the wire, or component. If possible secure before soldering a joint.

David Jones
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