Grapple Voltage Terminal

A "Grapple Voltage Terminal" is a console that is used for providing power to a door or mechanism. They are often seen with varying levels of energy, either not enough or too much to sustain a mechanism. Many of them power shields blocking doors. To fix the problem, Samus is required to take or give energy into the Terminal in order to disable a shield or power a mechanism.

Pirate Homeworld
The majority of Grapple Voltage Terminals in Corruption appear on the Pirate Homeworld. One is seen in the Command Courtyard, powering shields blocking access to the Skyway. An Assault Power Trooper is seen disabling the shields by interfacing with the console and then walking into Skyway Access before the shields come back up. Samus does not have the Grapple Voltage at this point, but even if she did, there is a constant downpour of Acid Rain in the Courtyard, which renders safe navigation impossible without the Hazard Shield.

Samus can use the Grapple Voltage immediately after the battle with Gandrayda, as a Grapple Voltage Terminal powers a shield blocking the door to Transit Station 1-B, which acts as a shortcut back to Landing Site Alpha. Draining the terminal of energy disables the shield, and Samus can proceed. The same process must be done at the Landing Site, where another shield can be deactivated from either side in the same fashion.

In Defense Access, a Grapple Voltage Terminal controls a shield on the right side, but it is on the inaccessible side of the shield. Samus enters that side after taking a detour in Skyway Access, and can drain the Terminal. Once the invasion of the Skyway is underway, Samus comes to Transit Station 1104, which is sealed off by a Grapple Voltage Terminal. Increasing its power supply by charging energy into it opens all the access doors for both Samus and her Federation Marine comrades.

A terminal exists at the bottom floor of the Command Station and can be drained of energy. This process disables an energy shield beside it that blocks the exit to the Morph Ball tunnels under the floor. Draining the shield enables Samus to enter and exit the tunnels. A Missile Expansion can be found under this shield. It is accessible on Samus' first trip through the Command Station tunnels, but the shielding cannot be disabled.

The last Homeworld Terminal exists in the Leviathan Access Portal room, that Samus comes to in order to board the Leviathan Battleship. However, both the Warp Site and Terminal are blocked by energy shields. Samus can circumvent this by using her Bombs to destroy a Talloric Alloy block in the wall behind the Warp Site, which will bring her to the terminal. Once it is drained, both shields will be disabled.

Elysia
Several Grapple Voltage Terminal-like obstacles can be found on SkyTown, Elysia during Samus' mission there, but it is only when she returns to search for the Spider Ball that she can use them. The first obstacle in Zipline Station Charlie, enroute to the Powerworks where the Spider Ball is located, is a gate with a Grapple Voltage Terminal that is low on energy. Supercharging it causes the gate to open.

The Construction Bay, enroute to Ballista Storage (which also features two Grapple Voltage Terminals), contains a Grapple Voltage Terminal near the entrance to the room. It activates a lift in a Morph Ball tunnel that allows Samus to take a shortcut in the room. Previously, this tunnel could not be accessed from the entrance.

In Ballista Storage, there are two turbines powering a lock mechanism on the wall. Overloading them with the Grapple Voltage destroys them and opens the lock, which reveals Energy Cell ID: GB-4913A-8.

Bryyo
A Grapple Voltage clamp that works much in the same way as the terminals do is found in the Hall of the Golems. This clamp is found over top of the Bomb Slot on a Bryyonian Golem and must be destroyed by overloading it to access the Slot. When activated, the Golem inserts its hands into a generator on the wall, which re-energizes a complex network of Spider Ball Tracks that Samus can navigate to reach a Missile Expansion.

Scans

 * Construction Bay:"Energy switch requires additional power to activate the connecting lift system."
 * Ballista Storage:"Turbine is supplying power to the lock mechanism. Overloading the system may disable the lock."
 * Zipline Station Charlie:"Gate is blocking zipline access. Energy lock is low on power and requires more to operate."
 * Command Courtyard/Defense Access:"Terminal controls the nearby energy shields*. Drain the device of power to remove the shields."
 * Flux Control:"Terminal is connected to the nearby lift system. Energize the terminal to restore lift operations."
 * Command Station:"Terminal is supplying power to a nearby energy shield. Drain the device to deactivate the shield."
 * Hall of the Golems:"Security clamp in place. Overloading the clamp with energy could destroy it."
 * Proving Grounds:"Terminal provides power to energy shield. Drain the device of power to remove the shield."
 * Transit Station 1104:"Terminal controls all nearby access doors, but is without power. Restore power to open all doors."
 * Leviathan Access Portal:"Terminal is powering the energy shield covering the transportation portal."

* Note: In the Command Courtyard, there are multiple shields, but in the other two rooms there is one shield, so "shield" in the scan is singular.

Trivia

 * The Grapple Voltage Doors mentioned in the Map key may have been a scrapped gameplay element and/or precursor to these terminals.
 * In Normal Mode, due to the differing rates of energy absorption/emission into Grapple Voltage Terminals - specifically absorption is about twice as efficient - Samus can utilize them to slowly but surely regain all her health by alternating charging and absorbing, as long as the terminal is not completely drained or energized. This will not work in Veteran or Hypermode, as in Veteran the rates are identical and Hyper the rate is in fact higher (causing increased life loss if repeated).
 * These terminals do not go named in the game, and do not have a name even in the internal objects data. The terminal is split into three models for the socket, meter and base, which are collectively referred to as "Grapple Voltage".