0
\$\begingroup\$

I've been trying to find any data sheets for either solderless or solderable breadboards to figure out what voltage/current should be safe to use on them, but either there isn't a single "official" data sheet out there or I'm just extraordinarily bad at googling stuff. From what I could gather most solderless BBs should have roughly the same characteristics, as they are pretty much the same underneath. As for the solderables, I found many types out there, all without "offical" voltage/amperage ratings.

I need to run 12V DC at ~2A continuously. Is it safe on solderless or solderable BBs?

\$\endgroup\$
  • \$\begingroup\$ Also depends on how well regulated you need the 12V to be, if the current is gonna vary and you have considerable resistance, the supplied voltage is also gonna change. So even if it is safe it might not be reliable depending on the application.. \$\endgroup\$ – Wesley Lee Mar 25 '15 at 5:12
1
\$\begingroup\$

It varies from stripboard to stripboard.

One location I found (which seemed to cite Vero, a major manufacturer of stripboard, though I couldn't follow the citation) says "For 1oz Vero with a trace width of 0.19mm the quote is for 3.5A @ 10C and 6A @ 30C" - the post seems to indicate that 1 oz is very common.

He does warn about the holes; the traces are smaller at the holes.

I have seen other sites which suggest soldering a wire along the track, to increase the current that can flow.

This is not original research, and I have no specific knowledge to confirm this. http://www.chatzones.co.uk/discus/messages/1218/2470.html?1141515383

\$\endgroup\$
  • \$\begingroup\$ Thanks, I guess I'll try a solderable one, and solder a wire along the track, as you said, that should help. \$\endgroup\$ – CivDav Mar 25 '15 at 5:25
1
\$\begingroup\$

I've had some experience with replacing a breadboard solution with a generic (solderable) perfboard one because of issues that built up over time.

I wanted to take a timelapse of a building under construction, which took several years. To this end, I placed an cheap and very old digital camera with an interval timer, and powered it through a DIY, UPS-like circuit. Wall-wart was giving me 6V@1A, which trickle-charged a Ni-Cd pack, and also powered the camera through a linear regulator to 3.3V. If mains went out, the Ni-Cd would take over for up to an hour or so. The current consumption of the camera was ~500 mA when in idle, with a bit more than 1A short bursts each hour, when a photo was taken.

All this being assembled in a hurry, I placed it on a small breadboard, and it worked like a charm, the timelapse was going on for more than a year, with regular servicing to download the CF card. And at some point it started to behave flaky. The camera would switch off when taking a photo, and when handled manually, it would also die sporadically. Initially I just put in more capacitance, but after measuring all voltages and inspecting under a 'scope, I moved the "UPS" to a generic perf-board. No problems since, handles it all very well.

While removing the components from the breadboard, I noticed the plastic around the linear regulator had had turned yellow, probably from the heat and the currents involved. The thing I want to stress here is that, initially, the breadboard was working very well. It failed after an year of usage - probably due to the slow oxide layer formation, which @PlasmaHH mentions.

Here's a photo of what the breadboard looks like now. As you can tell, the linear reg (a TO-220 part) was sitting in G3-G5:

breadboard damage

To reinforce PlasmaHH's conclusion: I myself would never trust a breadboard for a continuous job when currents exceed 100 mA. Short-term applications for less than a week should be okay with more.

\$\endgroup\$
0
\$\begingroup\$

With 12V 2A you have 24W at your hand, which might go in large amounts into one place, depending on what mistakes you might make. The breadboard strips can handle this just fine, but

  • the plastic will often melt and deform at surprisingly low temperatures (Varies a lot, I have seen it happening at ~60°C)
  • the contacts between components and strips as well as between the strips have rather high resistance, causing lots of additional power dissipated there
  • the strips are relatively thin, so that even when they do not melt, they will get deformed
  • the material is often suboptimal, causing it to build up a high resistance oxide layer when getting hot (again happening at surprisingly low temperatures)

In short: if you have more than a few hundred milliamps, go for the stripboard.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.