Shore power load planning
Check whether a campground pedestal, driveway outlet, or adapter-limited hookup can carry your AC, charger, microwave, water heater, space heater, and kitchen loads at the same time.
Quick shore-power read
30A RV service at 120V provides about 3,600W, while the entered stack is 4,850W. Shed at least 1,250W before relying on this overlap.
Service capacity
30A x 1 leg
Entered stack
135% of total pedestal watts
Continuous margin
Move about 1,970W out of the sustained stack
This is load-overlap planning, not an electrical approval. Verify pedestal condition, cord and adapter ratings, EMS protection, breaker limits, and 50A leg balance before relying on the result.
Start over
This calculator stores inputs locally in this browser. Clear saved inputs when stale values are getting in the way.
Shore power load calculator
Pick the available shore-power service, add the loads that may overlap, and include charger draw. The useful answer is not just total watts. It is which loads need to be timed, shed, or run alone.
Shore power check
30A RV service at 120V provides about 3,600W, while the entered stack is 4,850W. Shed at least 1,250W before relying on this overlap.
Service capacity
3,600W
30A x 1 leg
Continuous target
2,880W
80% planning target
Entered load
4,850W
135% of total service watts
Recommended service
50A RV service
Based on total watts, not 50A leg balance
Margins
Breaker margin
-1,250W
Compared with the full pedestal wattage.
Continuous margin
-1,970W
1,970W should move out of the sustained stack.
Load-shedding ideas
Turn down the converter or inverter-charger
900WCharging batteries is often the easiest sustained load to reduce while the AC, microwave, or water heater runs.
Shed Electric water heater
1,400WThis load is a good candidate to turn off first when breaker margin is tight.
Watch-outs
This is load-overlap planning, not an electrical approval. Follow RV, pedestal, adapter, EMS, breaker, cord, and appliance ratings before plugging in.
A dogbone adapter changes the plug shape; it does not create more amps. A 50A rig plugged into a 30A pedestal still needs to behave like a 30A rig.
Low pedestal voltage makes high-current loads harder on motors, compressors, chargers, and cords. Use an EMS or surge protector with voltage protection when possible.
Recommended next move
Move high-draw appliances out of the same time window, turn down the charger, or use a higher service before running this stack.
Why this exists
A 30A pedestal can run plenty when loads are timed well, but the same pedestal can trip quickly when the air conditioner, charger, microwave, and water heater stack up. This calculator helps you decide what belongs in the same time window before a breaker or hot adapter makes the point.
Use this with
RV shore power guide
Use this when you need the 30A vs 50A basics, adapter limits, and safe hookup habits.
Read the RV shore power guideBest RV surge protectors
Use this after the load math to choose protection against bad pedestal conditions.
Compare RV surge protectorsGenerator size calculator
Use this when the same appliance stack also needs to run from a portable generator.
Run the generator size calculatorInverter size calculator
Use this if you are moving some AC loads to battery and inverter power instead.
Run the inverter size calculatorTool notes
This output helps you decide whether a shore-power source has enough practical wattage for the loads you plan to overlap. It does not inspect pedestal wiring, cord condition, adapter quality, breaker health, voltage stability, or 50A leg balance.
15A, 20A, and 30A service are treated as one 120V leg. 50A RV service is treated as two 120V legs for total watts.
The calculator multiplies service watts by your continuous-load target so long-running stacks do not sit right at breaker capacity.
Appliance watts and battery-charger watts are added together, then compared with both the full service capacity and the continuous target.
Avoid these traps
A 50A-to-30A dogbone lets the plug fit, but the rig still has to behave like a 30A rig. The adapter does not create another 20 amps.
A converter or inverter-charger can quietly take hundreds or thousands of watts while batteries recover. That draw counts against the same pedestal as the AC and microwave.
Low voltage makes tight shore-power plans rougher on motors, compressors, and cords. Breaker math is only one part of the safety picture.
Treat the calculator result as a planning range, then verify the relevant manufacturer guidance, safety limits, installation requirements, and local rules before changing the rig.See assumptions
Gear to compare after the math
These handoffs match the calculator family, not a one-click prescription. Verify fit, specs, clearances, and install limits before buying.
SOK SK12V100P 12V 100Ah LiFePO4 Battery
Best for
Budget lithium builds after a smaller bank result
A common 100Ah building block when the calculator result still fits a straightforward 12V lithium bank.
Current listing
SOK SK12V100P 12V 100Ah LiFePO4 Battery at SOK.
Victron SmartShunt 500A/50mV
Best for
Making battery runtime visible instead of guessed
A shunt-based monitor is the usual next buy when the calculator result depends on real state-of-charge tracking.
Current listing
Victron SmartShunt 500A/50mV at Victron.
Victron Orion XS 12/12-50A DC-DC Battery Charger
Best for
Improving recharge support for larger daily loads
Use this class of DC-DC charger when the battery answer only works if drive-day recovery is part of the plan.
Current listing
Victron Orion XS 12/12-50A DC-DC Battery Charger at Victron.
Frequently asked
A 30A RV hookup is usually one 120V leg, or about 3,600 watts at 120V. A 50A RV hookup is typically two 120V legs, or about 12,000 total watts, but this calculator does not verify whether loads are balanced across those two legs.
Eighty percent is a conservative planning target for sustained loads like electric heat, water heating, charging, and air conditioning. Short bursts can sometimes exceed that, but a comfortable plan does not depend on running near the breaker for hours.
Use the AC input draw from your converter or inverter-charger manual if you have it. If you only know DC charging output, divide charge watts by roughly 0.82 to 0.90 and round up.
No. This is load planning only. A proper EMS or surge protector checks conditions this calculator cannot see, including high/low voltage, wiring faults, and pedestal problems.