Blue Sea Systems
Blue Sea 5029 ST Blade Fuse Block wiring diagram
12-circuit ATO/ATC blade fuse block with cover and a common positive bus. No negative bus: connect load returns to a separate negative bus. 100 A maximum per block, 30 A per circuit, 32 V DC maximum. Fuses sold separately.
- Compatible systems
- 12 V / 24 V
Wiring diagram
How the BS 5029 is wired.
Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.
Blue Sea 5029: twelve ATO/ATC fused positive branches, 100 A maximum total, 30 A per circuit and 32 V DC maximum. Load returns need a separate negative bus. The example load and fuse ratings are planning choices; verify actual loads, conductors, source protection and fuse interrupt ratings. Fuses are sold separately. Manufacturer installation manual
Edit this wiring exampleCable sizing for this example
Use the diagram as a starting point for your installation. Replace the example equipment and cable lengths with your own, and check the connections against your exact model's instructions.
Cable sizes depend on the connected equipment, current and cable lengths. Add those details in Crimp to size each run.
Installation notes
Before you install.
Open a question for model-specific guidance and sources.
Verified against the manufacturer's documentation, checked 2026-11-10. Manufacturer documentation →
What does the Blue Sea 5029 connect?
The Blue Sea 5029 ST Blade Fuse Block distributes one positive feed to twelve ATO/ATC fused circuits and includes a cover. It has no negative bus. Connect each load's negative return to a separate negative bus connected to the source. The 5026 is the twelve-circuit version with a negative bus.
The manufacturer's specifications set limits of 100 A for the whole block, 30 A per circuit and 32 V DC. Fuses are sold separately. These limits do not choose the correct fuse for a particular load or cable.
How are the terminals arranged?
IN + represents the common #10-32 feed stud. Terminals 1–12 are the #8-32 branch screws, each supplied through its own fuse position. The 5029 wiring schematic shows the single common positive bus and twelve fused outputs.
The block's branch fuses do not protect its incoming cable. Select upstream protection for that cable and verify the installed fuse's DC interrupt rating against the actual source. The editable example uses one illustrative load with a separate negative return; replace its demand and cable lengths with your installation values.
Technical reference
Specifications and terminal map.
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Catalog specification
12-circuit ATO/ATC blade fuse block with cover and a common positive bus. No negative bus: connect load returns to a separate negative bus. 100 A maximum per block, 30 A per circuit, 32 V DC maximum. Fuses sold separately.
- Compatible systems
- 12 V / 24 V
Terminal map
IN + is the common #10-32 positive feed stud; 1–12 are the fused #8-32 branch screws. There is no negative bus. Feed stud torque: 24 in-lb (2.71 N·m); branch screw torque: 18 in-lb (2.03 N·m). Protect the feed separately upstream.
IN +
positive · input
1
positive · output
2
positive · output
3
positive · output
4
positive · output
5
positive · output
6
positive · output
7
positive · output
8
positive · output
9
positive · output
10
positive · output
11
positive · output
12
positive · output
Sources and sizing method
Equipment specifications. Model details, ratings and terminal roles come from the catalog. Check your unit’s label and current manufacturer documentation for its exact revision.
Example sizing. Wire sizes and fuse ratings apply to the connected example, not a fixed cable size for this component. Set your actual equipment, current, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with BS 5029.
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