RV Shore Power Wiring: How to Wire a 30-Amp Shore Power Inlet
Shore power gives your van battery a reliable, fast charge at campgrounds and wherever 120V is available. Here's how to wire it correctly.
What shore power does in a van
A shore power connection allows you to plug into a standard campground pedestal (30A 120V) or household outlet (15–20A 120V) and charge your house battery bank through a converter/charger or inverter-charger.
Without shore power, your only charging sources are solar and the vehicle alternator (via DC-DC charger). Shore power adds a third source — reliable, location-independent charging at ~60–120A depending on charger size.
Components needed
Shore power inlet: A mounted exterior socket that accepts the shore power cord.
- 30A RV inlet: NEMA TT-30R female inlet — accepts the standard RV shore power cord
- 20A inlet: NEMA L5-20R or standard 20A outlet box — for household extension cord connection
Shore power cord: The cable between the campground pedestal and your van. Typically 25–50 feet. The van side plugs into your inlet; the campground side plugs into the pedestal.
Converter/charger or inverter-charger: The device that takes 120V AC input and produces DC charging current for your battery. This is the critical component — see RV converter-charger guide and inverter-charger vs inverter guide.
Wiring: 10 AWG 3-conductor cable from inlet to charger.
Optional: 30A breaker between inlet and charger (some builds, required by some standards).
Wiring the shore power inlet
NEMA TT-30R inlet wiring
The TT-30R inlet has three pins:
- Flat vertical blade (hot): Black wire
- Flat horizontal blade (neutral): White wire
- Round (ground): Green wire
Connect 10 AWG stranded wire to each terminal. Route the cable through the van wall (weatherproof entry) to the charger's AC input terminals.
Route and secure the cable
Shore power AC cable runs alongside but separated from DC wiring where possible. Where they must run together, cross at right angles rather than running parallel to minimize electromagnetic coupling.
Secure every 12–18 inches. If the cable runs through a wet area (near the shore power inlet, which may be exposed to rain spray), use conduit or weatherproof cable wrap in that section.
Connect to the charger
The charger's AC input terminals accept the hot, neutral, and ground connections from your shore power run. Follow your specific charger's wiring diagram — the charger manufacturer's documentation supersedes general guidance.
Polarity matters for 120V: Reverse polarity (swapping hot and neutral) causes equipment malfunction and is a safety hazard. Verify wiring with a non-contact voltage tester after first connection.
Breaker installation
A 30A breaker between the inlet and charger provides overcurrent protection for the AC wiring inside the van. This is good practice even if your charger has internal protection.
Install a DIN-rail mounted 30A breaker in a small enclosure near the charger. Wire: inlet → breaker → charger AC input.
Surge protection
An RV surge protector inline on the shore power connection (between the pedestal and your van's inlet) protects your equipment from campground power problems: low voltage (brown-out), high voltage spikes, and reverse polarity at the pedestal.
Products: Progressive Industries EMS-PT30X ($80–120), Surge Guard 34850 (~$80). These are well worth the cost — campground power quality varies significantly.
Ground fault protection
Shore power at campgrounds should have GFCI protection at the pedestal. Your van's charger should also be ground-fault protected per its internal design. For extra safety in wet outdoor environments, a GFCI inline adapter on the shore power cord adds another layer.
After wiring: testing
Before plugging into shore power for the first time:
- Verify all connections are correct with a multimeter (continuity check, polarity)
- Plug into shore power with the charger switched OFF
- Check inlet voltage with a voltmeter: should read ~120V hot-to-neutral, ~120V hot-to-ground, ~0V neutral-to-ground
- Switch charger on and verify it enters charging mode
- Monitor for 5 minutes — check for any warm connections or burning smells