What Guage Wire For 50 Amp Service

fifty amp is one of the most common amperages we need a gauge, billow, or a wire for. The cardinal questions regarding the l amp wire include:

What is a wire size for 50 amps 240 volts? (fifty amp wire judge; NEC lawmaking applies)
Wire size for l amp sub panel 100 feet away? (Here we volition have to business relationship for voltage loss)
What electric devices tin you run with a 50 amp wire? (Wattage will depend on voltage)

Let's starting time articulate the AWG wire judge size:

If you cheque the wire gauge ampacity chart here, you tin see that there are 3 AWG wire sizes that have ampacity near 50 amps. These are:

8 AWG wire with 50A ampacity (also small).
6 AWG wire with 65A ampacity (just right).
iv AWG wire with 85A ampacity (too big).

Now, choosing the 8 AWG wire with 50A ampacity seems like a skilful choice as a fifty amp wire size, right? Nonetheless, in almost all cases, the correct 50 amp wire size is six AWG with 65A ampacity. That is truthful for any voltage; 12V, 110V, 115V, 120V, 220V, 240V, you name it.

Why is that?

Nosotros have to account for the 80% breaker rating rule, set by National Electric Code (NEC) rules. Maximum loading for any branch circuit is lxxx% of the rating of the circuit for ampacity of wire for whatever load.

Let's take a quick look at how you can choose the right AWG estimate wire for 50 amps (or any amps for that matter). Subsequently on, nosotros will also look at when 6 AWG wire is not adequate as a 50 amp wire (due to voltage loss at a distance), and what you can run with a 50 amp 110V or 220/240V excursion:

50 Amp Wire Size (Using NEC 80% Rule)

You can't use 50A ampacity wire to create a 50 amp electrical excursion. If you do that, you will probable fry the circuit.

The lxxx% rule serves as a safety mensurate. You should at least have that extra twenty% on top of 50A ampacity.

Hither is how you lot summate at least how much ampacity should a 50 amp wire accept:

Wire Ampacity For fifty Amps = 50A / 0.viii = 62.5A Wire

That means that you should use a wire that can handle 62.5A as a fifty amps wire. At present, nosotros don't have 62.5A wire. The closest wire we take is the 6 AWG wire with 65A ampacity.

Note: Y'all can always use a bigger wire but never a smaller wire. For 50 amps, you could use 4 AWG wire with 85A ampacity (a bit of overkill simply information technology's OK), but you tin never use 8 AWG wire with 50A ampacity (you will fry the circuit).

In well-nigh cases, 6 AWG is an nigh perfectly-sized wire for a l amp breaker. In express cases, you volition probably take to utilize a larger 4 AWG wire. That'southward when you have a long circuit and are sending electrical electric current at some distance (100 feet or more).

50 Amp Wire Size 100+ Feet Away (Account For Voltage Drop)

Fifty-fifty you lot're sending electricity through a long distance (for example, to a 50 amp sub panel 100 feet abroad), y'all have to account for voltage drop.

A good dominion of pollex for voltage drib is this:

For every 100 feet, voltage drops by 20%.

In guild to get the same wattage (power) at the sub panel 100 feet away, y'all have to increase the amps by 20% (to residue out the 20% driblet in voltage).

That, of course, means that you are dealing with more current (more amperes) and y'all have to choose a bigger-sized wire.

Example: 50 amp wire is usually the 6 AWG (nosotros require at least 62.5A and vi AWG tin can handle 65A). If you have to power an electric device 100 anxiety abroad, you need 20% amps more. Instead of 62.5A, you're looking at 62.5A × 1.2 = 75A.

In this instance, the six AWG estimate wire with 65A will not be plenty. We need at least 75A. The next wire size that tin handle more than than 75A is the 4 AWG gauge wire. This ane can handle at 85A and is usually used as a 50 amp wire size for 100 anxiety away sub panels.

There are quite a lot of questions regarding l amp and different voltages. Let's tackle this 1 too:

What Size Wire Do I Need For 50 Amp At 110-240V?

A common misconception regarding l amp wire is that we need unlike wire sizes for different voltages. We don't need a bigger (or smaller) wire size for 50 amp at 240V than for 50 amp at 110V, for instance.

In all cases (with the exception when we take to business relationship for voltage loss) we employ 6 AWG wire for l amps.

Now, the wire size and the amps might be the aforementioned. With different voltages, nosotros don't go different amps; we get unlike ability (wattage).

For example, 50 amp wire on a 240-volt circuit can handle up to 12,000W of power (this is a very common electricity setting for RVs). Here is how you can calculate that:

Wattage = Amps × Volts = 50A × 24oV = 12,000W

If y'all have a 110V excursion, the l amps volition produce v,500W of ability.

We hope the topic of 50 amp wire sizes is a bit more clear now. Yous can besides check out a like postal service for: