Why do some elevators have a single call button and others two?

When multiple elevators are in use, the up and down (call) buttons serve to tell the system whether or not to stop an elevator at that floor. For instance, you are on the 5th floor and you want to go down.

1. Why are there two elevator call buttons?
2. What is the difference in elevator buttons?
3. What is a call button on an elevator?
4. Does it matter which elevator button you press?

Why are there two elevator call buttons?

Two Call Buttons are used outside the Elevator to determine which Direction you'll be going and to avoid the elevator reach maximum capacity by putting request calls on HOLD by preventing to halt on floors where the person wants to travel an opposite direction.

What is the difference in elevator buttons?

The two buttons available to call an elevator have an up arrow and a down arrow. These are meant to indicate whether you want to go up or down, not whether the elevator must come up or down. For example, if you're on Floor 3 and you want to go to Floor 7, you need to press the Up arrow button.

What is a call button on an elevator?

All elevators in the building have an Emergency Telephone Call Button built into their control panels. When the button is pressed, you are placed in contact with the building's Security Operations Center. The Call Button can be identified with a Å symbol.

Does it matter which elevator button you press?

You press ONLY the one for the direction you want to go, and cars continuing past you in the other direction ignore it. Outside every lift/elevator. there are 2 buttons, one showing up arrow and another showing down arrow.