Quick Hits

⚡ NEC Article 120 — Load Calcs Won't Kill You

🚐 Episode 44 — RV Parks: Every Site Gets a Starting Number

Article: 120 — Load Calculations
Part: Part VIII — Recreational Vehicle Parks and Recreational Vehicle Sites
Section: 120.130
Format: Quick Hit

🎯 What You'll Learn

RV parks have their own load-calculation rules.

Instead of starting with a generic receptacle calculation, 120.130(A) establishes a specific baseline VA load for each recreational vehicle site based on the type of supply facilities provided.

📖 The Quick Hit

🚐 120.130(A) — The Baseline Load

Each RV site gets a calculated load based on the type of electrical supply provided.

🔌 50-Ampere Sites

For sites equipped with 50-ampere, 208Y/120-volt or 120/240-volt supply facilities:

➡️ 12,000 VA per site

This is the biggest baseline value in the section.

🔌 20-Ampere + 30-Ampere Sites

For sites equipped with both 20-ampere and 30-ampere supply facilities:

➡️ 3,600 VA per site

🔌 20-Ampere-Only Sites

For sites equipped with only 20-ampere supply facilities:

➡️ 2,400 VA per site

⛺ 20-Ampere Tent-Camping Sites

For sites supplied by 20-ampere facilities and intended for tent camping only:

➡️ 600 VA per site

So the quick-reference breakdown is:

50A → 12,000 VA

20A + 30A → 3,600 VA

20A only → 2,400 VA

20A tent camping only → 600 VA

🔌 Shared Sites & Multiple Receptacles

What happens when a location can serve two recreational vehicles?

Section 120.130(A) provides a special rule tied to 551.77.

If a location serves two recreational vehicles, the load calculation is based on only the two receptacles with the highest ratings.

You don't simply add every receptacle at the location.

🧠 Why This Matters

This is another example of the NEC using a specific load-calculation method rather than simply adding every possible connected load together.

When you're working an RV park calculation, identify:

1️⃣ How is the site equipped?

⬇️

2️⃣ Determine the applicable baseline VA

⬇️

3️⃣ Check whether the location serves two recreational vehicles

⬇️

4️⃣ If so, identify the two highest-rated receptacles

That gets you to the proper starting point before moving through the applicable demand-factor rules.

🧠 Exam Takeaway

When you see 120.130(A), think:

🚐 RV park / recreational vehicle site

🔌 Specific VA baseline per site

⚡ 50A 208Y/120V or 120/240V → 12,000 VA

🔌 20A + 30A → 3,600 VA

🔌 20A only → 2,400 VA

⛺ 20A tent camping only → 600 VA

And remember the two-RV rule:

Use the two receptacles with the highest ratings.

🎯 Test Yourself

Per 120.130(A), what is the baseline VA per site for a location equipped with 50-ampere, 208Y/120-volt supply facilities?

A) 2,400 VA
B) 3,600 VA
C) 12,000 VA
D) 600 VA

✅ Answer

C) 12,000 VA

A recreational vehicle site equipped with 50-ampere, 208Y/120-volt or 120/240-volt supply facilities has a baseline calculated load of:

12,000 VA

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🔎 NEC References

Primary: Article 120, 120.130(A)

Related: 551.77 — Recreational Vehicle Sites

Related: Part VIII — Recreational Vehicle Parks and Recreational Vehicle Sites

⚡ Series Progress

Article 120 — Load Calcs Won't Kill You

🚐 Part VIII — Recreational Vehicle Parks and Recreational Vehicle Sites

Episode 41: Hospital Receptacles Get Their Own Discount Table
Episode 42: Patient Care Circuits Get Their Own Rule Too
Episode 43: Marinas: Shore Power Gets Its Own Discount Curve
Episode 44: RV Parks: Every Site Gets a Starting Number

➡️ Next Up

The series continues through Part VIII — Recreational Vehicle Parks and Recreational Vehicle Sites.

Next section: 120.130(B) and beyond.