I was watching "Better Call Saul" and came across this electrical device. I have never seen such a device. I want to know what it is called and what does it do/measure?
Here is another angle.
That's a Hollywood service panel. In the same way that's a Hollywood starship. (pretty sure real starships won't look like that.)
Here's what a real service panel looks like. By the way, Better Call Saul is set in 2002, six years before Breaking Bad began.
Unfinished wall area optional; all the wires could be hidden behind studs and drywall and covered right up to the edge of the panel cover, though that makes the electrical system less maintainable. And by the way, the cables bundled like that is illegal, cables need to cool.
The switch in the upper left is the main; throwing it would do the trick.
That said, the fiction may be trying to express that there's some sort of "smart home" equipment going on here, and that might look exactly like that. That did exist; it just wasn't purchasable at Home Depot and didn't talk to Siri. However, this would only switch the lights; if this scene also cut receptacles and other fixed loads (HVAC?) then only a madman would build a system like that. In 2002 if you shut off power to a PC, you lost all your work. Smart-home gear had two forks of development:
In practical shooting terms, if they had built this set from scratch, they could have had this control actually work the lights. However, I have to guess they rented/borrowed this facility to shoot in. In that case, this is most likely a security panel and has nothing to do with the lights. Right around the corner is a gaffer's best boy, who is throwing the lights off simultaneously.
Now here's an important fact about film/TV lighting. The ordinary lights in a location are not nearly enough. You need to pile on thousands of watts of additional lighting - just shooting a cozy 2-person "between two ferns" shot calls for 2-3 500W halogen fill lights. The problem is light is exponential - double your lumens and you only gain 3db of light. Office lighting is required by law to be a certain light level... If you try to shoot in that, you get very grainy shots and your project looks like Blair Witch or Cloverfield. Seriously, installed lighting in a room (or a desk lamp in a "between two ferns" shot) is nothing but a prop. It doesn't provide enough light to be useful.
So in that scene, there might be 10,000 watts of additional lighting thrown onto the room behind. The down-lighting is cool, but why is the ceiling so bright between the down lights? Because down lights do not work that way, the ceiling should look almost black in a photo like this because that's how cameras see it. That considerable amount of light is coming from the TV lighting that was added to the room.
Anyway, one of two things is possible, either the gaffer is throwing the room light switches and added lighting simultaneously (which seems like it would have a chance of causing messed-up takes)... or they have pulled apart the room light switches or supply and tied them into their gaffer board so they throw together.
It's also possible they even changed the bulbs in the lights, so the characteristics matched - you can't have that copious TV lighting switching off instantly because it's LED, whilst the actual room downlights fade out because they're halogen. That would look stupid.
I'm not even starting into matching color temp and CRI, and CRI is more critical because camera eyes aren't human.
The generic term for something like that is a "BMS", for Building Management System and that would be the building manager's remote access panel for it, the real system would be a set of PC monitor screens in a control room somewhere. The BMS will control the HVAC and lighting at a basic level and sometimes the intrusion and fire alarm system are rolled into it rather than have separate systems.
Can a BMS be used to kill power in an entire building? Yes, as part of the Fire Protection system, in which case it does so by tripping the main circuit breaker as a safety measure to avoid collateral damage from electrical fires. Typically in a BMS that has this capability however, it will not kill power to emergency systems like exit lights, door controls and elevators and will ALSO automatically call the Fire Dept.
How it all works in a TV show plot has only an indirect relation to the real world.
Certainly a security panel given the show. Also, there is an eye icon on the button directly below the screen, so those two things indicate a monitoring system. It could double as a fire alarm system as well.
Based on the deleted comments, it seems like you are looking to buy something like that. Product recommendations are off topic, but if you web search for fire security electrical control panel, you might see some similar things.
Let's breakdown the given picture of the electrical device and see its functional components.
They are namely,
1. Up/Down buttons 2. Left/Right buttons 3. Display 4. Key insert slot 5. Numeric buttons
Upon Google image searching (as mentioned by UnhandledExcepSean) the following query "fire security control panel", devices with similar functionality could be found.
Notice the Up/Down Left/Right buttons, Key insert slot, Display etc. These devices closely resemble the form and functionality of the device in the question posted, although minor differences in layout can be seen which can be due to two main reasons. 1. The device in the original question can be a "mock". 2. Different companies have different models and layouts.
In the second picture posted in the question, a number "6500" can be seen. Predicting this as a model number of the device and modifying the Google search as "fire security control panel 6500" or "fire security control panel model 6500" couldn't give exactly same results as the op, which can tell two things, 1. The device is a "mock" 2. It is not a model number.
All evidence suggest that there is a high probability that the device is a Fire Alarm Control Panel.
As far as the question whether a Fire Alarm System can shut down electricity in an office building is beyond the level of my expertise and I restraint myself from commenting on it.