Want to make a 16 feet long molex cable for my pumps

KING2882000 · 5 Nov 2017 at 21:41

Hello

I dont want to have my Radiators and Pumps near me so i wanted to make two 16 feet long molex cables for my two aquastream xt ultra pumps. Is there a Risk of cable fire, if i cut a molex extension in half and solder 16 feet of 1.5mm² cables inbetween them? I use a Dark Power Pro 11 1000W PSU.

Thank You

Jokester · 5 Nov 2017 at 21:44

No, it’ll be fine.

KING2882000 · 5 Nov 2017 at 21:57

I already asked that in a German Forum and they told me that in worst case could run the full 40A of my PSU Rail through that cable and it could burn if there is some kind of error. But if that is true, why are my normal 60cm Molex cables not already burning? I just dont want that my cables burn. Btw I would cover every single soldering point with a heat shrink.

Jokester · 5 Nov 2017 at 22:28

Yes, you’ll definitely need to insulate the joints to prevent short circuits!

bremen1874 · 5 Nov 2017 at 22:46

If you're concerned add an inline fuse into the extension wiring.

EsaT · 6 Nov 2017 at 08:44

For such long cables you'll want to increase cross section notably to make sure voltage losses stay under control during say higher start up current.

And like warned about burning cables, if say pump short circuits resistance from all that wire could prevent power supply's OC/SC protection from triggering...
While cabling itself is still getting fried because of needing to dissipate outputted power.
So adding fuse to extension would be sensible.

vapor matt · 6 Nov 2017 at 21:31

I would buy a 10amp + PSU with variable voltage from a amateur radio emporium and run the pumps from that, you have a choice of switch mode or linear PSU. I run my pump from a PSU using 18v as the D5 can take 24v which means more flow.
that way you can have PUMP's PSU closer to where the rads and pumps are.