Tricks for cutting long wires of equal length?

[AlaskanNoob]

I've got to cut some 130 foot 10 AWG wires for an install, just want to make sure they're actually equal length. Any tricks anybody use for this? I saw a device called a CutFox 10 that is a machine that does this (not sure if it would do 130 foot length or not) but haven't seen any reviews of it so not sure it's worth it.

 

[AlaskanNoob]

This thing looks like it might make it easy to measure wire lengths. Use the TLAR method with a little extra to cut the wires, then use this machine to fine tune them to the same length: https://www.greenlee.com/us/en/meter-cable-length-clm-1000-clm-1000

 

[Mike 134]

Put 2 marks on the floor 130' apart and cut. use a heavy object at the far end to hold them equal. Don't overthing this.

 

[SparkyJJO]

If it was me, I'd measure out and cut the first one, then use it at a template to cut the rest. I don't think equal lengths means it has to be down to the last 1/8".

 

[TomC4306]

I just unrolled it in the street with my brother the whole spool and then doubled it back upon itself. Match the ends up, go back to the u-turn, stretch, cut.
Didn't require $1,000 tool.

 

[DPC]

That's a cool tool.
Nothing worse than looking at a job and measuring it then getting a roll of cable and finding out your short.

I'm going to send a link to that to my boss.....

 

[TacomaJoe]

I'm going to ask the question; why the need for equal lengths?

 

[AlaskanNoob]

I'm going to ask the question; why the need for equal lengths?

Creating a positive 130' wire, and a negative 130' wire, from an array of 7 x 440W panels in series, to a charge controller. My understanding is these two wires need to be the same length. Why they need to be the same length is beyond my "one apple and one apple is two apples" level of science understanding though.

 

[DPC]

I've got to cut some 130 foot 10 AWG wires for an install, just want to make sure they're actually equal length. Any tricks anybody use for this? I saw a device called a CutFox 10 that is a machine that does this (not sure if it would do 130 foot length or not) but haven't seen any reviews of it so not sure it's worth it.

Just so I am clear..
You have a roll of single conductor #10?

Your going to put that in something right?
Like PVC conduit?

There is a relatively inexpensive approved cable type called NMWU
That stands for non metalic wire underground... ( means it has no metal on the outside just a jacket of plastic
Thats the right stuff for putting in the ground.
Follow local rules for how deep and cover with sand in a trench lines with some pea gravel to protect it from stones...
Put a piece or barricade tape between the cable and surface that says danger underground cable....
Take lots of pictures and measure exactly where it is for future reference

Follow local codes....

 

[DPC]

Creating a positive 130' wire, and a negative 130' wire, from an array of 7 x 440W panels in series, to a charge controller. My understanding is these two wires need to be the same length. Why they need to be the same length is beyond my "one apple and one apple is two apples" level of science understanding though.

Just get them as close as reasonably achievable.
This is not like fixing a watch or building a ship in a bottle...

 

[AlaskanNoob]

Just so I am clear..
You have a roll of single conductor #10?

Your going to put that in something right?
Like PVC conduit?

There is a relatively inexpensive approved cable type called NMWU
That stands for non metalic wire underground... ( means it has no metal on the outside just a jacket of plastic
Thats the right stuff for putting in the ground.
Follow local rules for how deep and cover with sand in a trench lines with some pea gravel to protect it from stones...
Put a piece or barricade tape between the cable and surface that says danger underground cable....
Take lots of pictures and measure exactly where it is for future reference

Follow local codes....

We have several rolls of 10 AWG, 7-strand, 600V/40A rated, direct burial wire that we need to cut into individual wires, then crimp MC4 connectors and ferrules to, to connect 7 arrays of 7 x 440W panels in series to our charge controllers. They will be in conduit from the ground mounts into the trench, then direct buried in ten foot deep trenches that extend to the charge controllers.

I want to make sure I cut the positive and negative wires for each array into equal lengths as accurately as possible.

 

[TacomaJoe]

In this case the wires don't need to be exact. In fact, if you have an array that is 20 feet wide, you can connect the positive at the nearside and the negative at the far side (20 feet further). The voltage drop is a function of both wire lengths so the shorter the better. The equal length wire idea comes into play when paralleling batteries so that they share the load equally. If you only have one battery the wires can be different lengths.

 

[AlaskanNoob]

In this case the wires don't need to be exact. In fact, if you have an array that is 20 feet wide, you can connect the positive at the nearside and the negative at the far side (20 feet further). The voltage drop is a function of both wire lengths so the shorter the better. The equal length wire idea comes into play when paralleling batteries so that they share the load equally. If you only have one battery the wires can be different lengths.

That's good to know. Each array will be 28 feet wide. I'll just eyeball it when I cut the wires and trench them then. Much appreciated.

 

[Checkthisout]

Aren't you pulling in conduit?

Anyway, the answer is simple.

Take your 700' roll, cut it into a single 520' length, then cut the 52p' length into 4 equal pieces, two of which you can use.

 

[Mattb4]

You can use a hose real. Simply measure the length of wire needed to go 1 revolution. Start winding wire on drum while counting each complete turn. If you do not get too many overlapping coils the size of a revolution will not change much. It does increase slightly but a few feet of extra wire does not hurt.

Example: it takes 24 inches of wire to go around once. You want 130ft , 130/2=65 revolutions.

 

[OzSolar]

That's a cool tool.
Nothing worse than looking at a job and measuring it then getting a roll of cable and finding out your short.

I'm going to send a link to that to my boss.....

I've seen them used at the supply houses to inventory how much wire is left on cutting spools.

 

[Checkthisout]

Why can't you just take a tape measure and measure out the lengths of wire as you pull it off the spool?

Even with 10' long tape, this process would take less than 5 minutes.