12V Blueprint MVP

Wiring diagram generator

Wiring Diagram

Configurable system layout

41.3A load
12V Electrical Schematic12V • 1× Lithium • 200Ah total • 3 loadsDWG-001Auto-generated+ BUS+ BANK− BUS (common return)Solar panel300WSolar controller40A MPPTINOUTSolar fuse30AAlternatorInput fuse50ADC-DC charger40AINOUTOutput fuse40AHigh-load fuse50ACompressor35.0ABranch fuse5AFridge3.8ABranch fuse5ALights2.5AHouse battery200Ah Lithium+−Main fuse50AIsolator100A6 AWG12 AWG12 AWG6 AWG6 AWG10 AWG10 AWG8 AWG6 AWG16 AWG16 AWG6 AWG12 AWG6 AWG10 AWG8 AWG6 AWG16 AWG16 AWGPositive (+) — fused near sourceNegative (−) — common return

Compressor is a high-current load; wire it from the distribution board through its own fuse and use a relay or heavy-rated switch.

DC-DC charger requires fuses on both input and output cables.

Fuse every positive cable leaving the battery near the battery terminal.

Return all grounds to the common negative busbar or a single battery negative point.

Daily Energy Budget

Charges fully each day with 91.9 Ah surplus.

SURPLUS
Used today
57.5 Ah
all loads combined
Recharged today
149.4 Ah
solar 110.3 Ah • alternator 39.2 Ah
Surplus / day
+91.9 Ah
available after today's loads
Usable battery
170 Ah
200 Ah installed capacity
Autonomy
3.0 days
normal daily use, no charging
Continuous runtime
4.1 h
all loads on, no charging
Charge limit
65.0 / 100.0A
within battery profile
Charger output
152.5 Ah
98% stored after battery chemistry losses
Per-load breakdown
  • Compressor17.5 Ah/day0.5 h/day
  • Fridge30.0 Ah/day8 h/day
  • Lights10.0 Ah/day4 h/day

Cable & Fuse Table

CircuitAmpsLengthCableFuseDropCheck
Alternator to DC-DC input40.0A4m6 AWG / 16 mm250A2.87%OK
DC-DC output to battery40.0A1.5m10 AWG / 6 mm240A2.87%OK
Solar panel to controller25.0A5m6 AWG / 16 mm240A2.24%OK
Solar controller to battery25.0A1.5m12 AWG / 4 mm230A2.69%OK
Battery to distribution41.3A1m8 AWG / 10 mm250A1.19%OK
Distribution board to Compressor35.0A4m6 AWG / 16 mm250A2.51%OK
Fuse block to Fridge3.8A3m16 AWG / 1.5 mm25A2.16%OK
Fuse block to Lights2.5A6m16 AWG / 1.5 mm25A2.87%OK

Parts List

  • 200Ah Lithium battery1
  • 40A DC-DC charger1
  • 300W Solar panel1
  • 40A solar charge controller1
  • Main battery fuse holder1
  • 100A battery isolator switch1
  • Positive busbar1
  • Negative busbar1
  • Blade fuse block1
  • Compressor relay or heavy switch1
  • 50A fuse3
  • 40A fuse2
  • 30A fuse1
  • 5A fuse2
  • 6 AWG / 16 mm2 copper cable26m
  • 10 AWG / 6 mm2 copper cable3m
  • 12 AWG / 4 mm2 copper cable3m
  • 8 AWG / 10 mm2 copper cable2m
  • 16 AWG / 1.5 mm2 copper cable18m