Engineering-related passage

My understanding of the following passage is limited by my lack of engineering knowledge, among other factors.

Two professors are looking over some electrical schematics a recently-deceased colleague has left behind.

A: ラインが多すぎる。なんでこんなに分けちまったんだ
B: ラインそれぞれの抵抗値を変えて切り替えさせる。
A: 動源が増えてる。

"There are too many [electrical] lines. Why were they divided [by the dead friend, probably] like this?"
"It switches out the lines by changing their resistance values."
"[So] the power increases/multiplies."

I have a few questions:

1) Does the above even resemble the actual translation?

2) I've been told that the 変える refers to the lines' resistance values and the 切り替えさせる refers to the lines themselves, correct?

3) Can anyone explain what's happening from an engineering point of view? I understand that shortening a line lowers its resistance and increases its power output. Why would dividing the lines cause them to switch out? The story has fantasy aspects, but I imagine (or hope) that the scenario has some sort of basis in actual engineering.

Thanks in advance, as always.

1) My interpretation (without knowing any further background)

A: There are two many lines. I wonder why (he) divided [the circuits, probably] like this?
B: We will vary the resistance for each of the lines, and [have someone] switch them around/change them around.
A: There are more power sources [than there were originally].

2) I believe so. "kirikaesaseru" implies that B is thinking about having someone change them, rather than B himself making the change. "kirikaeru" means "to switch," and "...saseru" is "have someone (do something)."

3) I have no idea :)

3.) I am guessing that possibly the current follows the path of least resistance (I dunno really though), so he could change the path of the current by increasing or decreasing the resistance of the wires.

Thank you both for your responses. (That "path of least resistance" factor never hit me till now.)

To add some background, the two professors are trying to figure out the intent behind their dead colleague's blueprints. B thinks he understands how the colleague's design is supposed to work and is explaining it to A. They're not going to change anything yet; they're just trying to understand the original system.

Therefore, to my understanding, the second line is an answer to the question of the first, and the third line is a statement/realization of the effect of the actions detailed in the second line. Of course, I could be wrong.

B continues the original exchange as follows: 「おそらく太田[the dead colleague]はそのつもりでこの値は設定した。前の公式から逆算するなら...」. After the calculations are finished (offpage), A realizes that the system does work. Would this line shed any light on matters?

(Another questions: To my understanding by later events, there seems to be only one power supply. "Fueru", though, seems to refer primarily to an increase in the _number_ of something, not an increase in magnitude or size, correct? The sentence couldn't mean that the power supply is just increasing in power output, could it?)