Editable DC examples

Campervan & RV 12 V wiring diagrams

Compare two 12 V campervan wiring diagrams with solar charging, a leisure battery, lights and a Maxxfan. The second adds charging from the starter battery through an Orion XS B2B charger. Cable tables show mm² and metres alongside AWG and feet. These DC planning examples exclude mains hook-up and inverter circuits.

mm² / metresAWG / feet

Simple solar and DC loads

6 components · 10 conductors · 12 V house system

Open this example in Crimp →

Live Crimp simulation. Try equipment states and battery charge, or choose Wiring to inspect the circuit. Cable IDs match the table below.

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Red = positive · dark = return. Crossings are not junctions. Read the assumptions before adapting a circuit.

Protection is unfinished. The shown fuse ratings do not select an exact protective device or locate it at the battery. Battery-end placement and unspecified-fuse warnings remain in Crimp. All charging and load currents below are design allowances, not measured operating currents.

Current engine findings

The fuse interrupt check uses the engine’s chemistry-based fault-current assumption. This is not measured fault current. Resolve the bank and protection design before installation.

Check the exact fuse, holder and battery evidence →

warning: Solar disconnection is missing (C7)
warning: Check fuse distance: 200 Ah house bank (C1, C9)
warning: Check fuse suitability: 200 Ah house bank (C1, C3, C5, C9)

Cable table — every displayed connection

Each length is one way. Drop is the engine’s run estimate including return, not a measured end-to-end system result; shared legs can have different conservative design-current bounds. “Pinned” marks a manufacturer-based example choice to review after edits. AWG is approximate; retain the stated conductor area when selecting actual wire.

Simple solar and DC loads cable schedule in metric with AWG
Circuit / endpoints	One-way length	Conductor	Design current	Fuse	Drop / allowance
C1 · 200 Ah house bank + ↔ Blue Sea 5026 ST Blade Fuse Block IN +	One-way length1 m3.3 ft	Conductor2.5 mm²AWG 13 · 35 A table	Design current7 A	Fuse10 A	Drop / allowance0.41% / 3%
C2 · 200 Ah house bank − ↔ Blue Sea 5026 ST Blade Fuse Block IN −	One-way length1 m3.3 ft	Conductor2.5 mm²AWG 13 · 35 A table	Design current7 A		Drop / allowance0.41% / 3%
C3 · Blue Sea 5026 ST Blade Fuse Block 1 + ↔ Cabin lights +	One-way length3 m9.8 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current2 A	Fuse3 A	Drop / allowance0.58% / 10%
C4 · Blue Sea 5026 ST Blade Fuse Block 1 − ↔ Cabin lights −	One-way length3 m9.8 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current2 A		Drop / allowance0.58% / 10%
C5 · Blue Sea 5026 ST Blade Fuse Block 2 + ↔ Maxxfan Deluxe 7500K +	One-way length2 m6.6 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current5 A	Fuse7.5 A	Drop / allowance0.97% / 3%
C6 · Blue Sea 5026 ST Blade Fuse Block 2 − ↔ Maxxfan Deluxe 7500K −	One-way length2 m6.6 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current5 A		Drop / allowance0.97% / 3%
C7 · Reference solar array + ↔ SmartSolar MPPT 100/50 PV +	One-way length3 m9.8 ft	Conductor4 mm²AWG 11 · 45 A table	Design current20 A	FusePV: review string protection	Drop / allowance1.31% / 3%
C8 · Reference solar array − ↔ SmartSolar MPPT 100/50 PV −	One-way length3 m9.8 ft	Conductor4 mm²AWG 11 · 45 A table	Design current20 A		Drop / allowance1.31% / 3%
C9 · SmartSolar MPPT 100/50 BATT + ↔ 200 Ah house bank +	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A	Fuse70 A	Drop / allowance0.46% / 3%
C10 · SmartSolar MPPT 100/50 BATT − ↔ 200 Ah house bank −	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A		Drop / allowance0.46% / 3%

Component table and exact example assumptions

Components in Simple solar and DC loads
Component	Ratings, role and assumptions
200 Ah house bankPlanning placeholder	12 V · 200 Ah 12 V, 200 Ah planning placeholder. Select an actual bank, compatible BMS, charge/discharge limits and battery-end protection. Ah does not select the fuse. Planning example, not installation approval. Batteries, the PV array and unnamed loads are placeholders. Battery acceptance, BMS controls, low-temperature charging, short-circuit current and runtime have not been verified. Fuse ratings are preliminary cable protection or stated manufacturer choices. Exact fuse/holder, DC voltage, interrupt rating and battery-end placement still need verification. Cable fuses have no physical placement here; the editor retains its battery-protection warnings. Lengths are physical one-way conductor runs. Voltage drop includes a return; shared paths use the engine’s conservative current bounds, not a prediction of simultaneous power flow. The calculation does not verify unequal shared-return lengths as one complete circuit. AWG labels are approximate table counterparts to metric conductors, not identical cross-sectional areas. Sizing uses Crimp’s ABYC-based tables for 105°C copper outside engine spaces, with no additional heat or bundling derating in these examples. Explicit 3% circuit targets and 10% cabin-light allowances are planning choices; terminals on placeholders carry generic planning limits, not verified connector ratings. US RV, UK campervan and Australian 4WD wording does not establish UK or AS/NZS installation compliance.
Blue Sea 5026 ST Blade Fuse Block5026	Blue Sea 5026: 12 ATO/ATC branches, 100 A maximum block total, 30 A maximum per branch, 32 V DC. Only two branches used. Input feed protection is separate; fuses are sold separately. Source: Blue Sea 5026 product page and wiring schematic, checked 2026-09-11.
Cabin lightsPlanning placeholder	12 V · 2 A load allowance 2 A continuous planning allowance. No measured duty cycle or energy budget.
Maxxfan Deluxe 7500KMaxxfan Deluxe 7500K	5 A load allowance 5 A minimum supply-service allowance from Airxcel 11E90001K (11-2017), not measured draw or startup current. Tagged black lead is positive. External fuse rating is a preliminary cable-protection choice.
Reference solar arrayPlanning placeholder	20 V · 20 A rated / planning output · 400 W · 24 V STC Voc 400 W / 20 V operating / 24 V STC Voc placeholder, not a selected panel. Actual Isc, cold Voc, temperature coefficient, string fuses and PV isolation must be checked. No yield claim.
SmartSolar MPPT 100/50SmartSolar 100/50	50 A rated / planning output SmartSolar 100/50, manual rev 12 (06/2026). Battery circuit sized at rated 50 A, not the reference array’s predicted output. 70 A example fuse is within the 55–70 A battery range; 16 mm² cable choice and 1 m battery run. Connect battery first, wait 10 seconds, check voltage, then connect PV. Configure the actual battery profile.

Solar plus alternator charging

8 components · 14 conductors · 12 V house system

Open this example in Crimp →

Live Crimp simulation. Try equipment states and battery charge, or choose Wiring to inspect the circuit. Cable IDs match the table below.

View full screen

Red = positive · dark = return. Crossings are not junctions. Read the assumptions before adapting a circuit.

Both chargers may charge the same bank. Verify their combined limit against the battery/BMS; the array does not guarantee the MPPT’s full rated output. Charger controls and a load disconnect are not modeled.

Current engine findings

The fuse interrupt check uses the engine’s chemistry-based fault-current assumption. This is not measured fault current. Resolve the bank and protection design before installation.

Check the exact fuse, holder and battery evidence →

warning: Solar disconnection is missing (C7)
warning: Check fuse distance: 200 Ah house bank (C1, C9, C13)
warning: Check fuse distance: AGM starter bank (C11)
warning: Check fuse suitability: 200 Ah house bank (C1, C3, C5, C9, C13)
warning: Check fuse suitability: AGM starter bank (C11)

Cable table — every displayed connection

Solar plus alternator charging cable schedule in metric with AWG
Circuit / endpoints	One-way length	Conductor	Design current	Fuse	Drop / allowance
C1 · 200 Ah house bank + ↔ Blue Sea 5026 ST Blade Fuse Block IN +	One-way length1 m3.3 ft	Conductor2.5 mm²AWG 13 · 35 A table	Design current7 A	Fuse10 A	Drop / allowance0.41% / 3%
C2 · 200 Ah house bank − ↔ Blue Sea 5026 ST Blade Fuse Block IN −	One-way length1 m3.3 ft	Conductor2.5 mm²AWG 13 · 35 A table	Design current7 A		Drop / allowance0.41% / 3%
C3 · Blue Sea 5026 ST Blade Fuse Block 1 + ↔ Cabin lights +	One-way length3 m9.8 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current2 A	Fuse3 A	Drop / allowance0.58% / 10%
C4 · Blue Sea 5026 ST Blade Fuse Block 1 − ↔ Cabin lights −	One-way length3 m9.8 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current2 A		Drop / allowance0.58% / 10%
C5 · Blue Sea 5026 ST Blade Fuse Block 2 + ↔ Maxxfan Deluxe 7500K +	One-way length2 m6.6 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current5 A	Fuse7.5 A	Drop / allowance0.97% / 3%
C6 · Blue Sea 5026 ST Blade Fuse Block 2 − ↔ Maxxfan Deluxe 7500K −	One-way length2 m6.6 ft	Conductor1.5 mm²AWG 16 · 25 A table	Design current5 A		Drop / allowance0.97% / 3%
C7 · Reference solar array + ↔ SmartSolar MPPT 100/50 PV +	One-way length3 m9.8 ft	Conductor4 mm²AWG 11 · 45 A table	Design current20 A	FusePV: review string protection	Drop / allowance1.31% / 3%
C8 · Reference solar array − ↔ SmartSolar MPPT 100/50 PV −	One-way length3 m9.8 ft	Conductor4 mm²AWG 11 · 45 A table	Design current20 A		Drop / allowance1.31% / 3%
C9 · SmartSolar MPPT 100/50 BATT + ↔ 200 Ah house bank +	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A	Fuse70 A	Drop / allowance0.46% / 3%
C10 · SmartSolar MPPT 100/50 BATT − ↔ 200 Ah house bank −	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A		Drop / allowance0.46% / 3%
C11 · AGM starter bank + ↔ Orion XS 12/12-50A IN +	One-way length3 m10 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A	Fuse60 A	Drop / allowance1.39% / 3%
C12 · AGM starter bank − ↔ Orion XS 12/12-50A IN −	One-way length3 m10 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A		Drop / allowance1.39% / 3%
C13 · Orion XS 12/12-50A OUT + ↔ 200 Ah house bank +	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A	Fuse60 A	Drop / allowance0.46% / 3%
C14 · Orion XS 12/12-50A OUT − ↔ 200 Ah house bank −	One-way length1 m3.3 ft	Conductor16 mm²AWG 6 · 120 A tablePinned choice	Design current50 A		Drop / allowance0.46% / 3%

Component table and exact example assumptions

Components in Solar plus alternator charging
Component	Ratings, role and assumptions
200 Ah house bankPlanning placeholder	12 V · 200 Ah 12 V, 200 Ah planning placeholder. Select an actual bank, compatible BMS, charge/discharge limits and battery-end protection. Ah does not select the fuse. Planning example, not installation approval. Batteries, the PV array and unnamed loads are placeholders. Battery acceptance, BMS controls, low-temperature charging, short-circuit current and runtime have not been verified. Fuse ratings are preliminary cable protection or stated manufacturer choices. Exact fuse/holder, DC voltage, interrupt rating and battery-end placement still need verification. Cable fuses have no physical placement here; the editor retains its battery-protection warnings. Lengths are physical one-way conductor runs. Voltage drop includes a return; shared paths use the engine’s conservative current bounds, not a prediction of simultaneous power flow. The calculation does not verify unequal shared-return lengths as one complete circuit. AWG labels are approximate table counterparts to metric conductors, not identical cross-sectional areas. Sizing uses Crimp’s ABYC-based tables for 105°C copper outside engine spaces, with no additional heat or bundling derating in these examples. Explicit 3% circuit targets and 10% cabin-light allowances are planning choices; terminals on placeholders carry generic planning limits, not verified connector ratings. US RV, UK campervan and Australian 4WD wording does not establish UK or AS/NZS installation compliance.
Blue Sea 5026 ST Blade Fuse Block5026	Blue Sea 5026: 12 ATO/ATC branches, 100 A maximum block total, 30 A maximum per branch, 32 V DC. Only two branches used. Input feed protection is separate; fuses are sold separately. Source: Blue Sea 5026 product page and wiring schematic, checked 2026-09-11.
Cabin lightsPlanning placeholder	12 V · 2 A load allowance 2 A continuous planning allowance. No measured duty cycle or energy budget.
Maxxfan Deluxe 7500KMaxxfan Deluxe 7500K	5 A load allowance 5 A minimum supply-service allowance from Airxcel 11E90001K (11-2017), not measured draw or startup current. Tagged black lead is positive. External fuse rating is a preliminary cable-protection choice.
Reference solar arrayPlanning placeholder	20 V · 20 A rated / planning output · 400 W · 24 V STC Voc 400 W / 20 V operating / 24 V STC Voc placeholder, not a selected panel. Actual Isc, cold Voc, temperature coefficient, string fuses and PV isolation must be checked. No yield claim.
SmartSolar MPPT 100/50SmartSolar 100/50	50 A rated / planning output SmartSolar 100/50, manual rev 12 (06/2026). Battery circuit sized at rated 50 A, not the reference array’s predicted output. 70 A example fuse is within the 55–70 A battery range; 16 mm² cable choice and 1 m battery run. Connect battery first, wait 10 seconds, check voltage, then connect PV. Configure the actual battery profile.
AGM starter bankPlanning placeholder	12 V · 80 Ah 12 V AGM source placeholder. Engine cranking and alternator are outside this drawing. No vehicle input headroom, idle output or factory wiring has been verified. Dedicated logical return: use the vehicle’s designated ground point where required by battery current sensing.
Orion XS 12/12-50AOrion XS 12/12-50A	50 A rated / planning output Non-isolated Orion XS 12/12-50A, rev 11 (06/2026). Logical IN− and OUT− represent its single physical GND terminal. Input/output limits are each up to 50 A; full output is not guaranteed at low input voltage. 60 A battery fuses and 16 mm² conductors are pinned choices. Remote/BMS control, charge profile, engine detection and alternator headroom require review.

Before adapting an example

What these drawings assume

These camper van and RV examples cover the 12 V DC house system. AC shore supply, inverter circuits, protective earth and mains distribution are outside the drawing. This is an editable circuit example, not a full electrical or energy calculator: battery capacity and solar yield still need your daily loads, climate and charging schedule.

Planning example, not installation approval. Batteries, the PV array and unnamed loads are placeholders. Battery acceptance, BMS controls, low-temperature charging, short-circuit current and runtime have not been verified.
Fuse ratings are preliminary cable protection or stated manufacturer choices. Exact fuse/holder, DC voltage, interrupt rating and battery-end placement still need verification. Cable fuses have no physical placement here; the editor retains its battery-protection warnings.
Lengths are physical one-way conductor runs. Voltage drop includes a return; shared paths use the engine’s conservative current bounds, not a prediction of simultaneous power flow. The calculation does not verify unequal shared-return lengths as one complete circuit. AWG labels are approximate table counterparts to metric conductors, not identical cross-sectional areas.
Sizing uses Crimp’s ABYC-based tables for 105°C copper outside engine spaces, with no additional heat or bundling derating in these examples. Explicit 3% circuit targets and 10% cabin-light allowances are planning choices; terminals on placeholders carry generic planning limits, not verified connector ratings. US RV, UK campervan and Australian 4WD wording does not establish UK or AS/NZS installation compliance.

For an inverter upgrade, read the single-120 V MultiPlus-II example. Its manual requires parallel DC cables; Crimp’s single-conductor calculation does not verify that pair. It is not part of either diagram here.

Adding monitoring or larger distribution changes the current paths. Read the SmartShunt return-path example and Lynx Distributor example, including their conservative series-current bounds and unresolved protection. The model pages keep those limitations visible.

Manufacturer evidence

Exact models and manuals

Checked 11 September 2026. Component notes identify the source-backed ratings and the choices made for this example.

Victron EnergyOrion XS 12/12-50A installation and cable/fuse tableRev. 11 — 06/2026, §3.3 and charger-mode connections; checked 11 September 2026. Single physical GND and external battery protection.Victron EnergyOrion XS 12/12-50A exact-model technical dataThe 50 A model’s input and output setting limits. These do not establish available vehicle power.Blue Sea SystemsBlue Sea 5026 product specifications and wiring schematic5026 with negative bus: 100 A block total, 30 A per branch, 32 V DC; fuses sold separately. Product page and linked schematic checked 11 September 2026; no revision stated.Victron EnergySmartSolar MPPT 100/50 installationRev. 12 — 06/2026, §4: battery protection, mounting and battery-first commissioning. Checked 11 September 2026.Victron EnergySmartSolar 100/50 technical specifications100/50 column: 50 A battery output, 100 V maximum PV Voc, 60 A maximum PV Isc. The reference array is not a selected panel product.Airxcel / MaxxairMaxxfan Deluxe installation and operating guide11E90001K — 11-2017, including 7500K, pp. 1–2. Minimum supply service, tagged positive lead and onboard fuse; checked 11 September 2026.

Keep goingWire size calculatorEnter one-way length, current and installation conditions to compare ampacity and voltage drop.Keep goingDC-DC charger size calculatorCheck vehicle headroom and battery acceptance before choosing a charging current.Keep going12 V boat wiring diagramsA boat engine, starter and house banks, bilge pump and navigation lights, plus the full onboard demo.Keep going12 V dual battery wiring diagramsStarter-to-auxiliary charging with Orion XS or REDARC BCDC1240D, plus protected house loads.Keep goingLiFePO₄ fuse size calculatorCheck exact fuse/holder, voltage, whole-bank fault current and placement evidence.Keep goingLead-acid to LiFePO₄ conversion guideReview charging, protection and monitoring when changing battery chemistry.Keep goingSizing methodologyRead the engine’s ABYC assumptions and limits before adapting an example.

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