relais-etanche-ip67-marine-12v-40a-30a-kit-complet-faisceau-5-fusibles

Kit relais étanche 5 broches 12V (NO/NC) pour usage marin, relais + socle IP67, faisceau précâblé avec porte-fusible en ligne, fusibles inclus (RW1240).

schema-cablage-relais-etanche-12v-40a-30a-positif-inverseur-expert-marine

waterproof-relay-wiring-diagram-12v-40-amp-30-amp-spdt-positive-trigger-marine

5-pin waterproof relay kit 12V DC (NO/NC) 40/30A, IP67 sealed connector and pre-wired harness with fuse holder — marine/automotive relay (RW1240).

40/30A Waterproof Relay Kit (12V IP67, Fused)

SKU: RW1240

9.50€; 9.50€
Unit price: per

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Description
Specification
How to use
FAQ
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Waterproof 5-Pin Relay Kit for Boats – IP67, 12V, 40/30A NO/NC, Fused Pre-Wired Harness

Baywatt's changeover relay is a sealed IP67 waterproof relay kit designed for wet and vibration-heavy environments on boats. It combines a 5-pin SPDT (NO/NC) changeover relay with a pre-wired sealed socket and a waterproof inline fuse holder, so you can control high-current equipment safely without sending heavy current through a small dash switch.

Marine-ready sealing: IP67 relay + sealed socket interface for moisture and spray exposure.
Real changeover logic: NO 40A (87) / NC 30A (87a) for standard ON control or “default ON” circuits.
Fused battery feed included: inline waterproof fuse holder already installed on the power input.
Pre-wired harness: 12 AWG power wires + 16 AWG trigger/ground wires for fast, clean wiring.
5 fuses included: 20A / 25A / 30A / 35A / 40A (ATO/ATC blade format).

Typical marine uses

Use the relay when you want a low-current switch (helm panel, push button, controller output) to drive a higher-current device with proper protection.

Deck / spreader / underwater lights
Horn / siren
Washdown, livewell, accessory pumps
Blowers / fans
Accessory power switching (when you want a protected, remote high-current path)

NO / NC - Changeover behavior

87 (NO – Normally Open, 40A): OFF by default, turns ON when the relay coil is energized.
87a (NC – Normally Closed, 30A): ON by default, turns OFF when the relay coil is energized.

This is useful for standard “turn ON when triggered” circuits (NO), and also for “turn OFF when triggered” logic (NC) such as safety/fail-safe or default-ON loads.

Pinout & wire colors (RW1240)

Positive trigger control: apply +12V to 86 to energize the relay coil, and connect 85 to battery negative.

Pin	Wire color	Function	Wire gauge
30	Red	Power input (Battery +) via waterproof fuse holder	12 AWG (≈ 3 mm²)
87	White	NO output (to device) – 40A max	12 AWG (≈ 3 mm²)
87a	Red	NC output – active when relay is not energized – 30A max	12 AWG (≈ 3 mm²)
85	Black	Ground / Battery negative (coil −)	16 AWG
86	Blue	Trigger signal +12V (coil +) from switch/controller	16 AWG

What’s included

1× IP67 sealed 5-pin relay (SPDT changeover, NO/NC)
1× sealed socket with pre-wired harness
1× waterproof inline fuse holder (pre-installed on the battery feed)
5× blade fuses: 20A / 25A / 30A / 35A / 40A
Mounting bracket (as shown)

Installation notes (marine wiring)

Select the fuse value based on the device and cable sizing, not “because the relay can do 40A”.
Keep the fused feed (pin 30) as close to the power source as practical.
For a water-resistant harness splice, use adhesive-lined heat shrink butt connectors and proper crimping.
NC (87a) is optional: leave it insulated if unused.

Specification

Technical specifications

Reference	RW1240
Relay type	5-Pin SPDT changeover relay (NO/NC)
System	12V DC (switching voltage up to 14V DC)
Contact rating	NO (87): 40A max / NC (87a): 30A max
IP rating	IP67 (sealed relay + sealed socket interface)
Operating temperature	−40°C to +85°C
Wire gauges	3 × 12 AWG power wires (≈ 3 mm²) + 2 × 16 AWG control wires
Wire mapping	30 Red (fused input), 87 White (NO), 87a Red (NC), 85 Black (ground), 86 Blue (trigger +12V)
Dimensions (approx.)	35 × 40 × 58 mm (L × W × H, with base)
Harness lengths (approx.)	Socket pigtails ~10 cm; fused lead ~20 cm
Fuse format	ATO/ATC blade fuse
In the box	Relay + sealed socket & harness + waterproof inline fuse holder + 5 fuses (20/25/30/35/40A)

How to use

How to use :

Discover tips, tricks, and detailed instructions on using our product in our dedicated blog post. Learn about setup, operation, and optimization to get the most out of your purchase.

Link to the blog

FAQ

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