I bought the linked a/c→d/c PSU 2nd hand. I did not look at the connector (assumed it was barrel) and just focused on power attributes. Then when I got home I noticed it has 4-pins. Luckily there is a diagram on the sticker, which says:
P1,2=+12v
P3,4=gnd
So I imagine P1 and P3 could supply 12v to a 12v device, and same for P2 with P4. Correct? I’m a bit surprised pins 3 and 4 are labeled ground and not negative. It’s a round connector, so I wonder if the outer ring is actually made to be negative. The a/c input is 3 pin (i.e. grounded).
I wonder if I am misunderstanding because I don’t get the point in 4 pins in this context. If the original appliance (LCD or whatever it is) needs two 12V supplies, why wouldn’t it simply be a 2 conductor barrel considering the appliance could internally wire two circuits in parallel?
I bought it to drive a device that needs a barrel. I’m not really happy to cut the connector off b/c I might one day end up with a 4-pin device, but I guess it’s not worthwhile to try to track down a 4-pin female tip locally to rig it up non-destructively.
To be clear, the appliance needs 12v 5A, which is how the 4-pin PSU is labeled. I hope it’s not a case where each of the 14v pins have 2.5A max.
5A max is certainly for the adapter, not the pins. Pins are an implementation detail, that sticker is telling you what the supply is capable of.
Also, check the power rating. 60W, 12V means a max 5A output.