Source extensions

[gastan]

My RV has two (2) 200W panels on the roof connected to a Victron 100/30 MPPT controller (factory installed).
It also has a factory installed Zamp port.
I am building a suitcase kit for when parked under obstructions (trees).
Panels: two (2) Newpowa 75W panels connected in series (already purchased).
Controller: Victron MPPT 75/15 mounted in the trailer next to the battery (already purchased).
Battery: SOK 206ah LiFePO4 (already installed in trailer).
I am rerouting the wires from the Zamp port from the factory wiring buss to the Victron controller.
I will route the wires from the controller back to the factory wiring buss.

I would like to use SAE connectors and have a 30-40 foot cable from the suitcase kit to the trailer.
Trouble is that I cannot find a SAE extension cable that long. They seem to max out at about 20 feet.

Two questions.
1. Does anyone know of a source for dual (twin) core cables with SAE connectors that are over 20 feet?
2. If long SAE extension can't be found, is it permissible to chain two shorter cables together to get the length I want?

I considered making my own cable. The cable is readily available but I can't find any SAE connectors, either. It seems that all SAE extensions have the connectors molded onto the cable and there are no DIY SAE connectors.

 

[Samsonite801]

Do you know what gauge wire you want to use?

Here's a 30ft cable but is 16 awg...

https://www.amazon.com/iGreely-Extension-Disconnect-Automotive-Motorcycle/dp/B08LR8X1HW?th=1

 

[gastan]

Thanks for the response.
According to this calculator ( https://unboundsolar.com/solar-information/voltage-drop ) a 30 run of 16awg wire would give me a 3.9% voltage drop and a 40 foot run would result in over 5% drop. Both too much, IMO.

A 12awg wire would be acceptable (both right at or below 2%) but 12awg is hard to find.
I can find several 15 or 20 foot 10awg cables and the calculator give a loss of 1.3% or less for them.

I contacted Zamp yesterday and was told that it is acceptable to chain two cords together but they advise not going over 30 feet.

I'll probably go with two 20 foot cords (in spite of Zamp's warning). Actually, that gives me some flex in usage and even at max length the drop would only be 1.3% (according to the calculator).

(I used Vmp (x2) and Imp in the corresponding boxes of the calculator. If I should have used Isc the drop are slightly higher - but still under 1.5%)

 

[Samsonite801]

Thanks for the response.
According to this calculator ( https://unboundsolar.com/solar-information/voltage-drop ) a 30 run of 16awg wire would give me a 3.9% voltage drop and a 40 foot run would result in over 5% drop. Both too much, IMO.

A 12awg wire would be acceptable (both right at or below 2%) but 12awg is hard to find.
I can find several 15 or 20 foot 10awg cables and the calculator give a loss of 1.3% or less for them.

I contacted Zamp yesterday and was told that it is acceptable to chain two cords together but they advise not going over 30 feet.

I'll probably go with two 20 foot cords (in spite of Zamp's warning). Actually, that gives me some flex in usage and even at max length the drop would only be 1.3% (according to the calculator).

(I used Vmp (x2) and Imp in the corresponding boxes of the calculator. If I should have used Isc the drop are slightly higher - but still under 1.5%)

Just my own opinion, I know you may like the SAE, that's fine, I understand the preference and it's fine. If it were me however, I might consider to just ditch the SAE, and make your own cable, using the gauge you prefer and the connector types you want. If the end only has SAE and panel has no pigtail to easily change the connector type, I might just make a shorter adapter cable.

I like the SAE fine for like on my motorcycle accessories and whatnot (shorter cables and such), but I have burned up a few when I would overcurrent them (of course lots of connector types would do that too based on the currents I was flowing there hehe), but I might just consider making a normal cable with MC4 ends on them and switch to those type.

Or another idea is just use the cable you want (gauge), and then crimp on SAE pigtail cords on each end (one SAE cord can be cut and make 2 pigtails. Then you get over the voltage drop, and have the SAE ends...