A separate trolling motor battery
Give the trolling motor its own battery and keep the chartplotter on a separate supply.
Follow the circuit
01
Trace two separate circuits
Each load returns to its own battery. There is no positive link between the motor and chartplotter banks, so motor use does not draw from the electronics battery.
02
Size for the motor
Minn Kota lists 50 A maximum draw and 60 A protection for 55 lb motors. The example uses short 16 mm² leads; longer runs need a fresh voltage-drop check.
03
Disconnect after use
The MKR-27's push-to-trip button opens the motor's positive feed. Minn Kota calls for disconnecting the motor when it is unused or its battery is charging.
The source and this example
Minn Kota's 12 V rigging drawing connects a trolling motor to a dedicated battery through overcurrent protection.
We use a 55 lb motor, a 110 Ah AGM battery and the recommended MKR-27 60 A breaker. The separate chartplotter circuit and short cable lengths are example choices.
- Minn Kota: 12 V rigging diagram ↗
- Minn Kota: wiring, protection and battery guide ↗
- Minn Kota MKR-27 installation manual ↗
60 A rating, BAT LINE / AUX LOAD connections and manual disconnection. DC interrupt capacity is not published here.
Before you build
- Match the motor voltage to its battery bank.
- Confirm the actual protection device's DC rating and interrupt capacity.
- Arrange charging for both batteries before the next trip.
This is a planning example. Cable sizing uses Crimp’s ABYC-based method; the drawing does not certify an installation.
Cable sizes and connections · 5 conductors
Lengths are one way. Sizes and currents come from the same Crimp model as the drawing. Each drop value covers one drawn conductor; the full circuit includes its supply and return. AWG values are approximate counterparts to the metric areas.
| Connection | Length | Wire | Design current | Fuse | Drop |
|---|---|---|---|---|---|
| C1 · Trolling battery + → Minn Kota MKR-27 DC Circuit Breaker 60A BAT LINE + | 15 cm | 16 mm²AWG 6 | 30 A | — | 0.04% |
| C2 · Minn Kota MKR-27 DC Circuit Breaker 60A AUX LOAD + → Minn Kota Trolling 55lb + | 1.4 m | 16 mm²AWG 6 | 30 A | — | 0.37% |
| C3 · Minn Kota Trolling 55lb − → Trolling battery − | 1.5 m | 16 mm²AWG 6 | 30 A | — | 0.41% |
| C4 · Electronics battery + → Chartplotter (Garmin GPSMap) + | 2 m | 1.5 mm²AWG 16 | 3.2 A | 7.5 A | 0.62% |
| C5 · Chartplotter (Garmin GPSMap) − → Electronics battery − | 2 m | 1.5 mm²AWG 16 | 3.2 A | — | 0.62% |
A dash means no fuse is assigned to that conductor; upstream protection may apply. Recheck the exact device, holder and placement after edits.
Equipment · 5 components
- Trolling battery
12 V · 110 Ah
12 V, 110 Ah AGM Deep Cycle (BAT412101084), rated at C20. Victron prefers charging at 0.2C (22 A); this is a recommendation, not an absolute maximum. Flat terminals have 8 mm through-holes.
- Minn Kota MKR-27 DC Circuit Breaker 60A
60 A manual-reset DC circuit breaker for Minn Kota motors on 12, 24, 36 or 48 V systems. Connect BAT LINE to battery positive and AUX LOAD to the motor. Push-to-trip also opens the supply; Crimp does not simulate automatic trip timing. The manufacturer manual does not publish DC interrupt capacity or an absolute maximum operating voltage.
- Minn Kota Trolling 55lb
30 A load allowance
Catalog model uses 30 A typical draw and 50 A maximum. Minn Kota's table specifies a 60 A breaker for 50/55 lb motors. The MKR-27 is the manufacturer's recommended breaker; its interrupt capacity remains unpublished in the reviewed manual.
- Electronics battery
12 V · 110 Ah
12 V, 110 Ah AGM Deep Cycle (BAT412101084), rated at C20. Victron prefers charging at 0.2C (22 A); this is a recommendation, not an absolute maximum. Flat terminals have 8 mm through-holes.
- Chartplotter (Garmin GPSMap)
3.2 A load allowance
GPSMAP 943xsv 9-inch chartplotter with sonar: 1.37A typical and 3.20A maximum at 12V, with 40.2W maximum at 10V. Accepts 10–32V DC and uses a 6A fast-acting fuse. The dedicated power harness is required even when connected to NMEA 2000.
Crimp checks · 3 findings to review
These are the current engine findings for the saved example. They remain visible when you open it in Crimp.
- warning: Check breaker protection: MKR-27 · 60A
- warning: Check fuse suitability: Electronics battery
- warning: No charging source
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Crimp for AI agents · public beta
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