How Many Amps Can You Put On A 175 Amp Service

200 amp wires are quite large. They tin can be used as 200 amp ground wires, wires for 200 amp breaker, they tin can be copper or aluminum 200 amp wires. The mutual question for all these applications here is this:

What size wire practice I need for 200 amp service?

If you await at the AWG gauge wire nautical chart hither, the respond seems to exist quite clear (it's not that elementary, however):

As yous tin can encounter, the obvious – merely wrong – the choice is using a #000 AWG wire for 200 amp service (also known equally three/0 AWG) considering it has a 200A ampacity. That, however, will likely end with you lot frying the wire.

For safety measures (in society to avoid frying a 200 amp excursion), the National Electrical Code (NEC) dictates the following requirement:

Maximum loading for any branch circuit is 80% of the rating of the circuit for ampacity of wire for any load. (NEC 220-two)

This is known as NEC 80% requirement for wire sizing. In the case of 200 amps breakers, this means y'all volition need a wire with at least 250A ampacity to connect a 200 amp service.

Looking at the AWG wire chart, you lot will need an even bigger than #0000 AWG wire for 200 amps. You have to go beyond the AWG nautical chart at expect at the KCMIL wire chart.

KCMIL wires are bigger and can handle currents of 200 amps and higher. Here is a shortlist of KCMIL wires that can be used for 200 amps:

250 KCMIL wire with 255A amperage.
300 KCMIL wire with 285A amperage.
350 KCMIL wire with 310A amperage.
400 KCMIL wire with 355A amperage.
500 KCMIL wire with 380A amperage.

The 250 KCMIL wire is the perfect size wire for 200 amp service considering it has 255A ampacity (a minimum of 250A ampacity requirement is satisfied).

We will bear witness yous how this 250A ampacity is calculated. On tiptop of that, y'all will also need a bigger wire gauge if you desire to send electricity 100 anxiety or 150 feet away from sub panel (nosotros will show y'all how to calculate what size wire you demand in this instance likewise).

200 Amp Wire Judge Calculation: What Size Wire You lot Need For 200 Amp Excursion?

To adequately determine the 200 amp wire gauge, you first need to calculate the minimum ampacity requirement as per the 80% NEC rule.

In the instance of the 200 amp excursion, here is how the calculation looks like (you have to go out 20% extra amps capacity for condom reasons):

200 Amp Wire = 200A × 100% / fourscore% = 250A Ampacity

That means that you can to use a wire that has an ampacity of 250A or college in society to ready a 200 amp excursion.

As you lot can run into from the list of KMCIL wires above, the 250 KCMIL wire is perfect for a 200 amp service since information technology has an ampacity of 255A.

Now, if the sub console is some distance away (50 anxiety, 100 feet, 150 feet, 200 anxiety, so on), you will probably take to use an fifty-fifty bigger wire to counted the voltage drop.

The NEC 310-16 requirements cover this nicely:

How To Account For Sub Panel Existence 100 Feet Away?

When sending electricity a long manner from the sub console, the voltage volition drop with the distance. To counter this drop, you have to heave the initial amps. That means that the circuit has to handle more amps; in turn, the wire you're using has to handle more amps.

How much more exactly?

Roughly speaking, the NEC 310-16 requirement states that for a 200 amp copper or aluminum wire, yous have to add 20% to the total amps for every 100 feet of altitude.

Example: Permit's say you want to use 200 amp service 100 feet away from the sub console. We already know that such a circuit will crave wires with at to the lowest degree 250A ampacity. On acme of this, we take to increase the amps by xx% to get the true size wire for 200 amps at such a distance:

200 Amp Wire (100 ft abroad) = 250A × 1.2 = 300A Ampacity

Now nosotros accept to find a wire with 300A ampacity or more. If you consult the KCMIL list above, you tin can see that the 350 KCMIL wire is perfect for 200 amp service 100 feet away. That'southward because information technology has a 310A ampacity.

You lot can make a similar calculation for 50 feet (ten% addition), 150 anxiety (30% improver), and 200 feet (40% addition), and choose the respective KCMIL wire.

Hopefully, at present the 200 amp wire sizing is a chip clearer.

Yous should too look into different amp wires and similar calculations for: