Contents
Are amps pushed or pulled?
One amp is equal to a flow of one coulomb per second through a wire. Making electrons flow through a resistance requires an attractive force to pull them. This force, called Electro-Motive Force or EMF, is measured in volts. A Volt is the force required to push 1 Amp through 1 Ohm of resistance.
How does a device know how much current?
Electrical loads such as appliances have resistance. That, together with Voltage determines the current they draw (see Ohms Law). Above the rated current, the wires in your wall plug transformer overheat and burn (if a fuse is not present).
When do people talk about ” drawing ” current, what?
By “drawing extra current”, most people mean exactly that, as for “being under [extra] load”, it means a similar thing, i.e. the device has to deliver more power to it’s load. If you think about it, if the current (and therefore power assuming constant voltage) in a motor decreased under heavier load,…
What do you need to know about powering devices?
There are three things you need to know about your device before you can select a power source or interface components; Is the device AC or DC powered, what voltage does it require to operate, and how much current does it draw.
How can you tell the current of a device?
Most AC powered devices will have a rating label on them – one that shows the voltage and, current or wattage, requirements. If the label only lists the voltage and wattage, you can get a rough estimate of the current by dividing the wattage by the voltage. It’s not exact, but it’s close enough for determining what interface components you can use.
What does it mean when a device is under load?
The fact that a device is “Under load” actually directly means that the device is simply using power or current from the supply. So, for any specific circuit, the heavier the Load becomes, the more current or power will be taken or drawn from the power supply.