DC Power Pigtails Male and Female: Is 18 awg sufficient?

Maybe this will help.  All wire has some resistance to current flow.  The bigger the wire (smaller wire Gauge number), the less resistance it has per foot.  For short runs 18 gauge wire should be ok, but for longer runs, 14 gauge is better.  In other words the resistance per foot adds up (more with smaller wire).  The specs on the barrel connector pigtails say it's good for 5 Amps or so (Z1000 = 5.5 Amps nominal).  18Gauge stranded is rated for about 10 Amps.

The shorter you can make the pigtail wires the better, as they will add less resistance compared to making up the length difference with 14Ga. wire.

Thanks. That is kind of my thinking on the matter.

WOW, those 14 awg pigtails that I found are $10 for 10 pairs.
Great price, right?

Get this: Shipping is $33
YIKES

Great price, but ouch on the shipping.  If it were my decision, I'd stick with what I had and keep the pigtails short.

@SteveH posted:

Great price, but ouch on the shipping.  If it were my decision, I'd stick with what I had and keep the pigtails short.

That is exactly what I did. Those pigtails are about 4" long.

Your short section of 18G wire will have more resistance than the 14G layout wire.  Check for heat in the short section while operating.  The Z1000 will probably be OK.  A Z4000 at 10A load may generate heat.

A long time ago, someone at my club used a banana plug harness from a RTR set to join a Z4000 with the track.  I don't know the gauge of the wires but they got hot enough to melt the insulation during an hours long show.

Do a search for ampacity of wire gauges. There are charts available that indicate how much amperage different gauges can handle. Some of these charts are 12 vdc references so you can take a conservative approach. 18 gauge wire can handle 10 amps for about 6-8 feet or so. That's why those short, 18 gauge Atlas clip leads work for drops from main wires.

I found a 14 awg DC Power Extension cable, 10 ft long, for $12 and change, at Amazon, and being a prime member, the shipping is free, so I ordered two one to use to make the cables that I need.

It is pure copper, and does have the 2.1mm x 5.5mm barrel ends, just like the 18 awg pigtails.
Also, this is even better than the pigtails, as the cables will have no splices in them. I can cut the full length that I need out of the new extension cable.

Of course I need a male and a female, and this will take care of that in fine fashion.

Just as some of the Amazon listings put 18AWG, 14AWG (or no indication at all) wire size, some include "5A" in the title.  A quick scan at DigiKey suggests 5A is the "sweet spot" for this size barrel connector, but there are some rated above and below.  It would be interesting to see if the sellers even know what was used.

@stan2004 posted:

It would be interesting to see if the sellers even know what was used.

And you assume the sellers even care!

@stan2004 posted:

Just as some of the Amazon listings put 18AWG, 14AWG (or no indication at all) wire size, some include "5A" in the title.  A quick scan at DigiKey suggests 5A is the "sweet spot" for this size barrel connector, but there are some rated above and below.  It would be interesting to see if the sellers even know what was used.

When I get the cable, I will compare it to known 14 awg wire, and take pics of that, as well as a comparison with the 18 awg pigtails that I have.

In the first Amazon listing I looked at for 18 AWG pigtails, the two "top reviews" by verified-purchase customers said the wire was 22 AWG instead of 18.  Kind of makes you wonder if it's like dimensional lumber where a 2 by 4 is not really 2 by 4.  Maybe with pigtails 18 really means 22 ...and 14 really means 18.

Sounds like someone might be "sizing" their wire based on the OD of the insulation.

I guess I am going to find out.