Hubbell Incorporated
Hubbell Incorporated HBL503NM 50 A Flanged Locking Inlet marine electronic
A 50 A flanged locking inlet with a self-closing cover and nickel-plated rear enclosure for corrosion resistance
- TypeLocking Devices
- Weight0.85
- 50 A flanged locking inlet for high-power marine connections
- Quick-connect design with backwards compatibility speeds installation
- Self-closing friction-tight cover protects contacts when not in use
- Neoprene gasket seals underside of cover against moisture ingress
- Nickel-plated rear enclosure resists corrosion in harsh marine environments
Marine power inlet for 50 A shore supply
The Hubbell HBL503NM is a flanged locking inlet built for marine electronics installations that require a 50 A non-NEMA connection. It suits boat owners and marine electricians fitting or replacing shore-power entries on vessels where a secure, lockable interface is specified. The nickel-plated rear enclosure resists corrosion in salt-spray environments.
Thermals and power draw in normal use
The inlet carries up to 50 A continuously through its locking contacts without active cooling. No fan or moving parts are present, so operation is silent and there is no parasitic power draw. The neoprene gasket under the self-closing cover maintains a weather-tight seal that prevents moisture ingress during normal dockside conditions.
Quick-connect terminals and sealing cover
Rear quick-connect terminals accept prepared conductors for faster installation while remaining compatible with existing wiring layouts. The friction-tight cover snaps shut automatically when the plug is removed, and the neoprene gasket on its underside preserves the seal against spray and splash. Nickel plating on the rear housing adds a further barrier against galvanic corrosion.
Highlights
- 50 A flanged locking inlet for high-power marine connections
- Quick-connect design with backwards compatibility speeds installation
- Self-closing friction-tight cover protects contacts when not in use
- Neoprene gasket seals underside of cover against moisture ingress
- Nickel-plated rear enclosure resists corrosion in harsh marine environments
Specifications
| Brand | HUBBELL |
|---|---|
| Type | Locking Devices |
| Weight | 0.85 |
Questions about this item
How do I mount the HBL503NM flanged inlet and what step is often missed?
Fasten the flange through its mounting holes, then press the self-closing cover until the neoprene gasket seats evenly — skipping the gasket check leaves a leak path.
What part of the HBL503NM will need replacement after extended marine exposure?
The neoprene gasket under the cover ages and hardens; replace it when the cover no longer seals tight against the flange.
What is the continuous current limit for the HBL503NM inlet?
The device is rated for 50 A continuous; sustained loads at that level will heat the nickel-plated rear enclosure first.
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