Current capacity

[snowdog]

Would anyone please point me to the page(s) that would give me the technical specifications of the LM3, LM3S and the LM4SG?

Specifically, I'm looking for the current capacity specs on these modules.

Thank you in advance,
Bryan

[G8B4Life]

The "technical specifications" for the LM-4S-G can be found in the instructions for the LM-4S-G vis: https://ringengineering.com/RailPro/Documents/LM-4SGInstructions.pdf.

For the others well let's just say that historically Ring has not published specifications for his products and for the most part still doesn't. I don't know what he's afraid of, seriously. However a few people in the years past have gotten some of that useful information out of Ring and posted it here. A quick search of the forum pulled up these:

Q. What is the maximum amperage rating of the LM2S?
A. The max stall current of a LM-2 is 2.0 amps.  The continuous running current should be less than 1.0 amp. The LM-2 motor output is short circuit, overload, and module over temperature protected.  So if you connect a motor that is too big for it to drive it will turn off and report one of the above faults.

and

The LM-2 can output 200mA on any one output and the total of all outputs simultaneously on can not exceed 200mA.

I strongly suspect the the LM3 and 3-S is the same as the LM2 in this regard.

- Tim

[snowdog]

Tim,

Thank you! I can't recall how many times I've looked at the spec sheet that comes with the modules and I NEVER saw what I asked for! Thank you!!!

Your suggestion to look at the sheet for the LM4-S lead to the LM3-S and there it was!
Stall current of 8 amps and throughput of 1.2.

Thank you for getting me on the right track! (pun intended)

Bryan

[gregeusa]

I found the stall current of 8 amps, and also the admonition that the power supply should not supply more than 12.

I cannot find the continuous current, which of course will be driven by how well the unit sheds heat.

So a 12 amp fuse inline with the power source might not be a bad idea.

Greg