Exactly, sure you could have relays or Automatic Transfer Switches like we use from generators. But if you're just slamming more power at stuff than it's meant to use, where's your overcurrent protection?
one of my favorite jokes about this is on TNG. i think it's the episode where the bridge gets cut off from the rest of the ship, and Troi is in charge of running the ship. O'Brian makes a comment to Ro about how you can't 'just reroute power from things'.
I don't know about you people, but personally, I always write programs at work by removing boards from my computer and plugging them in a different order.
Judging from what things look like when they open up the walls, they could just be telling the system to use a specific circuit path. It looks like everything is just a bunch of blocks or cards with super dense computer chips on them and half the repairs we ever see are just these being unslotted and replaced. The other half being waving fake tools around.
you can't just "re-route power" by pressing buttons on a screen and not, you know, actually unhooking any wires!
High-voltage switches might be a bit complicated. One I've seen requires you to tighten a spring and then have it released extremely fast to prevent sparking. Still, there should be a way to do it safely, without having to go near or touch the wiring.
Once again I remind you all that these consoles are not powered by a substance as boring as regular electricity. Oh no. It has to be highly energetic tuned plasma...straight to the user interface consoles...for, uh, reasons.
The reason is because the engines produce this material as a waste product. So instead of venting it into space it's processed and funneled back through the ship to power everything from lights to equipment.
Very efficient and very VERY dangerous. Many Vulcans retired from the VSA because Humans pulled shit like this.
Wouldn't it be easier and safer to just use it to generate boring old electricity and send that through the ship? Maybe the danger is there to keep the crew excited and working at maximum efficiency...
All I'm saying is, there's no way this would pass a MIL-STD-882 safety assessment in the twenty first century. So I have no idea how they got their spaceworthiness certificate.
Battle shorting the practice of negating the fuses in a ship or other war machine because a blown fuse disabling a key system could lead to the loss of the whole ship in battle, and the equipment can maybe work over its rated limit for a time when necessary. Cathode Ray Dude did a video about it.
https://www.youtube.com/watch?v=wpJ_6LCly4A
"In a battle or emergency, where the survival of the vessel (or other protected asset) is dependent upon the continued operation of the equipment, it is sometimes wiser to risk equipment damage than have the equipment shut down when it is needed. For example, the electrical drives to elevate and traverse the guns of a combat warship may have "battleshort" fuses, which are simply copper bars of the correct size to fit the fuse holders, as failure to return fire in a combat situation is a greater threat to the ship and crew than damaging or overheating the electrical motors."
Another problem is about where to redirect the overcharge. In space there is no ground where the current can go. Yet you need to dissipate the energy somewhere.
It's probably grounded to the hull somewhere, put in a couple electric gizmos and feed the power back into your batteries. Now the enemy is charging your ship while they blow it up because you didn't turn on your sheild.
Do we have fuses that can safely dissipate like 350Megajoules? I don't remember which specific episode it was, but I remember on DS9 they were going to overload the warpcore to stop something and someone said the only system on the station capable of absorbing that much raw electrical energy was the shield system, since that's literally what it is; a giant fuse.
Fuses don't dissipate electricity. They pass electricity and then blow when exceeded. Blowing is either flipping off (like your breaker) or breaking (like replaceable fuses). The point of a fuse is to be the weakest link so if a surge occurs it doesn't damage equipment or wiring.
In the case you described, they were looking for a load (where energy is used or dissipated to do work) to absorb that much energy at once. There might be a fuse that could withstand that kind of load; there was wiring that could afterall. But if the shield system could absorb the full power of an overloaded warp core, it might not have needed one if there was no downside to overcharging it.
Hum... I have a 75MJ varistor on each phase of the main wiring of my house. Those are not fuses (because fuses don't have a total energy specification) but I can certainly get a few more for the Enterprise it they want.