Blue Sea PowerPost & PowerBar: Stud Size and Wiring Guide

Blue Sea PowerPost connectors provide secure places to join large electrical cable lugs or distribute connections in tight spaces. This comparison covers Dual PowerPost sets for cable extensions, PowerPost Plus junctions with small-wire screw terminals, and the 200-amp PowerBar that joins two studs on one copper bus.

Which kind of electrical connection is needed?

Dual PowerPost

2016, 2017 and 2018 provide large terminal posts with red and black insulators. Used for extension points and large cable-lug connections.

PowerBar

2019 uses two 3/8-inch studs on a common tin-plated copper bus, rated to 200 A at up to 48 V DC.

PowerPost Plus

2101, 2102 and 2103 pair a central large power stud with smaller screw connections on a 150 A bus.

Dual PowerPost cable-connection sizes

These models are intended as connection points for larger cables, including suitable outboard-engine harness extensions.

MPN Design Stud threads Voltage / rating
2016 Dual PowerPost Two 5/16–18 studs 48 V DC max
2017 Dual PowerPost Two 3/8–16 studs 48 V DC max
2018 Dual PowerPost One 5/16–18 and one 3/8–16 48 V DC max

Blue Sea 2019 PowerBar is a separate design

MPN Design Stud threads Published rating
2019 PowerBar Two 3/8–16 studs on common bus 200 A; 48 V DC max

Unlike a pair of individual posts, the 2019's two terminals share an electrical bus. Make sure that connection is appropriate to the intended circuit before replacing a Dual PowerPost arrangement.

PowerPost Plus stud sizes and branch screws

MPN Design Main stud threads Published rating
2101 PowerPost Plus One 1/4–20 × 1 in stud 150 A; 48 V DC max
2102 PowerPost Plus One 5/16–18 × 3/4 in stud 150 A; 48 V DC max
2103 PowerPost Plus One 3/8–16 × 3/4 in stud 150 A; 48 V DC max

The manufacturer specifies #8–32 screw connections for the smaller conductors and an insulating cover with the PowerPost Plus models. The 150 A current rating belongs to the connection bus, not to every individual attached wire.

Electrical installation and fit checks

Select the terminal stud and cable lugs by exact size. Size conductors and upstream protection for the actual load and fault current, and keep insulated terminals protected from accidental contact. Follow Blue Sea's specified terminal torque and marine electrical installation guidance.

Do not use the stated bus rating as the fuse size

A 200 A PowerBar and a 150 A PowerPost Plus have different connection layouts and are not interchangeable with separate harness-extension posts. Confirm the complete circuit before moving cables between them.

Blue Sea insulated connection posts and PowerBar

Select a matching model below for details and current availability.

Other marine electrical connection guides

Marine fuse blocks and battery terminal fuse holders

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