AGL Component Library By Precision AGL Academy

Connector Storage / Parking Receptacle

A dedicated mounting receptacle designed to safely store and protect unused L‑823 primary plugs when they are disconnected from isolating transformers or equipment. It provides a secure, weatherproof docking station that prevents damage to the plug's contacts, seals, and threads, ensuring the connector remains in optimal condition for future use.

Connector Storage / Parking Receptacle

Image disclaimer: For identification and illustration only. It may show a product by another manufacturer and may not depict the exact item described; it is not a statement of any product’s quality, approval or performance. Third-party image and trademark rights belong to their owners. See full notice.

Overview

What Is It?

The Connector Storage / Parking Receptacle (also known as a parking receptacle, storage socket, or dummy receptacle) is a purpose‑built mounting socket designed to receive and protect an L‑823 primary plug (or secondary plug) when it is not connected to its intended equipment. It provides a safe, organised, and environmentally protected storage location for disconnected cable plugs, preventing damage, contamination, and corrosion that could compromise the connector's performance when it is later reconnected.

Key characteristics of parking receptacles include:

  • Mates with L‑823 / Secondary Plugs: Designed to the same dimensional and thread specifications as the equipment receptacles, ensuring a proper fit with the plug's coupling ring and seals.
  • IP68 Sealing: When the plug is mated and torqued, the parking receptacle provides the same watertight sealing as the equipment receptacle, protecting the plug's contacts and seals.
  • Mounting Provisions: Features a flange or mounting bracket for secure attachment to junction boxes, equipment panels, or structures.
  • UV‑Stabilised Material: Constructed from corrosion‑resistant materials such as brass, stainless steel, or UV‑stabilised engineering plastic, ensuring long‑term outdoor durability.
  • Colour Coding: Often painted or marked in a distinctive colour (e.g., yellow or blue) to clearly identify them as parking receptacles and distinguish them from active equipment receptacles.

Parking receptacles are an essential accessory for AGL maintenance and installation, providing a designated "home" for disconnected plugs and preventing them from being left dangling, damaged, or exposed to the elements.

Purpose

Purpose & Function

The parking receptacle exists to solve a very practical field problem: a disconnected plug left dangling or lying on the ground is exposed to moisture, dirt, and physical damage that can degrade its seals and contacts before it's ever reconnected, potentially introducing a fault into a circuit that was working perfectly before the plug was removed. Giving that plug a dedicated, sealed home during maintenance or reconfiguration keeps its performance intact for whenever it's needed again.

This matters because AGL series circuits depend on every connector maintaining its watertight integrity — a single degraded connection can introduce resistance or moisture ingress that affects the whole loop. The distinctive colour coding also serves a real safety function, making it obvious at a glance which receptacles are active equipment connections and which are simply parking points, preventing a technician from mistakenly treating a storage socket as a live connection.

Application

Where Is It Used?

Parking receptacles are used throughout the airfield wherever primary or secondary plugs may be disconnected and need safe storage, including:

  • Junction Boxes and Handholes: Parking receptacles are mounted inside or on junction boxes, providing a convenient storage location for disconnected primary plugs during maintenance or circuit reconfiguration.
  • Transformer Housings: Some isolating transformer housings incorporate a parking receptacle for storing the primary plug when the transformer is taken out of service.
  • Distribution Panels and CCR Enclosures: Parking receptacles are mounted on panels to provide storage for primary plugs disconnected from CCR outputs.
  • Test Points and Disconnect Panels: When a plug is removed from a test point, it can be parked in a nearby receptacle to keep it clean and protected.
  • Equipment Shelters: Inside equipment shelters, parking receptacles provide organised storage for spare or disconnected cable assemblies.
  • Maintenance Vehicles and Workshops: Portable parking receptacles are used in maintenance vehicles and workshops to store spare cable assemblies during transport.

The parking receptacle is available for both primary (L‑823) and secondary connector types, with the appropriate thread size and sealing profile for each application.

Placement

Installation & Location

Parking receptacles are fitted at the point a plug is likely to be disconnected — mounted inside or on junction boxes, integrated into transformer housings, fixed to distribution panels and CCR enclosures near their output connectors, or mounted at test points and disconnect panels. The receptacle is positioned close enough to its associated plug's normal connection point that a technician can park the plug immediately after disconnecting it without laying it on the ground, and its own mounting includes a sealing cap or cover so it keeps the same environmental protection whether or not a plug is docked in it. Portable versions are fitted inside maintenance vehicles or workshop storage to hold spare cable assemblies in transit, following the same principle of giving a disconnected plug a clean, secure resting place rather than leaving it exposed.

Function

How Does It Work?

The parking receptacle provides a secure, protective docking station for an unused plug. Its design mimics the critical features of an equipment receptacle:

  • Threaded Outer Shell: The parking receptacle features external threads that engage with the plug's coupling ring. When tightened to the recommended torque, it compresses the plug's internal O‑rings, creating a watertight seal that protects the plug's contacts and seals.
  • Contact Sockets: The receptacle contains socket contacts (or blank inserts) that receive the plug's pins, preventing mechanical damage to the pins and providing a clean environment for the contact surfaces.
  • Mounting Flange: A flange with screw holes allows the receptacle to be securely mounted to a junction box, panel, or structure, ensuring it remains in a fixed, accessible location.
  • Sealing: Internal O‑rings (or a sealing cap) maintain the IP68 protection when the plug is fully mated, preventing moisture and contaminants from reaching the plug's contacts and seals.
  • Identification: The parking receptacle is typically colour‑coded or marked to clearly distinguish it from active equipment receptacles, reducing the risk of accidentally connecting to the wrong port.

When a plug is parked in the receptacle, it is held securely and protected from environmental damage, mechanical stress, and contamination. This preserves the plug's condition and ensures it is ready for reliable reconnection when needed.

Architecture

System Architecture & Control Logic

The parking receptacle carries no control logic and sits outside the active series circuit — it is not wired into the loop the CCR regulates, and a plug docked in it draws no current and is invisible to the ALCMS, the CCR, and any loop-level fault reporting. This is precisely its function: a spare plug (from a decommissioned fixture, a spare secondary lead, or a unit pulled for maintenance) needs somewhere to sit that is electrically inert, so it cannot be mistaken for a live connection point or accidentally introduce a stray path into an energised loop. Because it presents no load and no conductive path, its condition (a degraded seal, a loose mount) never shows up in loop voltage or current readings the way an in-circuit fault would; verifying it is doing its job — keeping a docked plug sealed and its contacts protected — is purely a visual and physical inspection task, not something the ALCMS can report on.

ALCMS / CCR — ACTIVE SERIES LOOP Regulates and monitors every in-circuit connection PARKING RECEPTACLE — NOT IN CIRCUIT No load, no current, no loop-level visibility ✕ Faults on this side (open lamp, failed transformer, broken conductor) raise loop voltage at constant current and are reported to the ALCMS as a loop fault. A docked plug's seal condition is never reflected in any electrical reading — the only verification is a physical torque and visual seal check in the field.
The parking receptacle deliberately has no electrical presence in the series circuit, so it can never be mistaken for an active connection point — but that also means its own condition has to be verified by inspection, not by the ALCMS.
Operating Principle

Sealed Docking for an Unused Plug

Plug Removed from Service, Unprotected Pins and contact surfaces exposed to moisture, dirt, and impact — risk of corrosion or bent pins before the plug is next put into service Plug Docked in Parking Receptacle Threaded coupling ring engaged Tightened to torque → O-rings compressed Contact sockets shield the pins Only the docked path preserves the plug's condition IP68 Maintained on the Docked Plug Ready for reliable reconnection when needed Left Loose: Degrades Over Time Contact resistance rises with corrosion
The parking receptacle re-creates the same coupling-ring-and-O-ring seal an active equipment receptacle would provide, so an unused plug stays protected and IP68-sealed until it's needed again — instead of sitting exposed with its pins at risk.
Construction

Physical Construction

The parking receptacle is typically a compact, moulded thermoplastic or die-cast metal housing incorporating a socket shaped to accept the mating L-823 primary plug (or secondary plug), with internal contacts electrically isolated or simply omitted since the receptacle carries no live circuit. A spring-loaded or hinged weatherproof cap covers the socket opening when not in use, and an O-ring or gasket seal at the mounting flange keeps moisture and debris out of the cavity. The receptacle is mounted to a base can, equipment cabinet wall, pole, or bracket via a threaded boss or bolt-on flange, positioned close to the equipment it serves so the disconnected plug can be stored without straining the cable. Drainage weep holes or a sloped cavity floor are commonly included to prevent water pooling inside the socket during storage.

Specification

Technical Parameters

ParameterTypical Value
Connector Type CompatibilityL‑823 primary (6.6A/20A) or secondary connector types
MaterialBrass, bronze, stainless steel, or UV‑stabilised polyamide
Mounting TypeFlange‑mount with screw holes or bracket‑mount
Sealing MechanismInternal O‑rings (compressed by plug coupling ring)
Protection Class (with plug mated)IP68 (submersible, continuous)
Operating Temperature-40°C to +85°C
ColourYellow, blue, or grey (typically distinctive for identification)
Thread TypeL‑823 standard or secondary connector standard
Recommended Torque3.5 – 5.5 N·m (L‑823); 2.5 – 4.0 N·m (secondary)
Electrical RatingNot applicable (storage only, no electrical connection)
StandardsFAA AC 150/5345-26, IEC 63067
Compliance

Applicable Standards

FAA AC 150/5345-26

Specification for L-823 Plug and Receptacle, Cable Connectors (includes parking receptacle dimensions)

IEC 63067

Connecting devices - general requirements and tests for AGL plugs and receptacles

ICAO Annex 14

General requirements for AGL circuit components and protection

Prerequisites

Installation Requirements

Mounting Location Selection
Preparation

Position the receptacle close to the equipment it serves, so the disconnected plug can be stored in it without straining or kinking the cable.

Housing Mounting
Mechanical

Fix the flange or bracket-mount housing to the base can, cabinet wall, pole, or bracket, torquing fixings evenly so the mounting flange gasket seals correctly.

Drainage Orientation
Mechanical

Orient the receptacle so its weep holes or sloped cavity floor drain freely, preventing water pooling inside the socket during storage.

Weatherproof Cap Check
Mechanical

Confirm the spring-loaded or hinged cap closes fully over the socket opening and its seal is undamaged before the receptacle is left unattended.

Identification & Labelling
Documentation

Label the receptacle to match the circuit or plug it is intended to store, since an unlabelled receptacle risks a mismatched connection later.

Sign-off
Documentation

Record the receptacle's as-built location and labelling before it is brought into use.

Verification

Testing & Commissioning

Fitment & Thread Engagement Check
Pre-Energisation

Confirm the receptacle accepts and fully seats a standard L-823 (or secondary) plug without cross-threading.

Corrosion & Contact Protection Check
Pre-Energisation

Verify internal contacts and threads are clean, uncorroded, and free of debris before the receptacle is put into service.

Mounting & Seal Verification
Pre-Energisation

Confirm the receptacle housing is securely mounted and any cap or seal excludes moisture when no plug is parked in it.

Identification & Labelling Check
Final Acceptance

Confirm the receptacle is labelled to match the circuit or plug it is intended to store, avoiding a mismatched connection later.

Documentation & As-Built Sign-off
Final Acceptance

Record fitment, corrosion, and labelling checks alongside the as-built location in the commissioning dossier.

Upkeep

Inspection & Maintenance

Presence & Fitment Check
Annual

Confirm the parking receptacle is present, correctly mated, and torqued to specification.

Thread Condition Inspection
Annual

Check receptacle threads for cross-threading damage or wear from repeated mating cycles.

Corrosion Inspection
Annual

Check the receptacle body for corrosion, particularly in humid or coastal environments.

Identification & Labelling Check
Annual

Confirm the receptacle is correctly identified and labelled to prevent connection to the wrong circuit.

Field Notes

Common Field Issues

Missing or Inadequate Parking Receptacles

If parking receptacles are not provided, plugs may be left dangling, unprotected, or placed on the ground, leading to contact damage, dirt ingress, and corrosion. Always ensure adequate parking receptacles are installed at maintenance points.

Cross‑Threading

Cross‑threading the plug into the parking receptacle can damage the threads, making it difficult to mate with the equipment receptacle later. Start the coupling ring by hand and ensure it threads smoothly before torquing.

Insufficient Torque

If the plug is not tightened to the recommended torque in the parking receptacle, moisture and contaminants can enter the plug. Use a torque wrench set to the manufacturer's specified value.

Corrosion of Parking Receptacle

In aggressive environments, the parking receptacle itself can corrode, making it difficult to remove the plug. Use receptacles made of corrosion‑resistant materials (stainless steel or brass) and apply anti‑seize compound to the threads if recommended.

Incorrect Receptacle Type

Using a parking receptacle that does not match the plug type (e.g., using a secondary receptacle for an L‑823 plug) will not provide proper sealing or protection. Always ensure the correct receptacle type is used.

Lack of Identification

If parking receptacles are not clearly identified, they may be mistaken for active equipment receptacles, leading to connection errors. Use clearly marked and distinctively coloured parking receptacles.

Mechanical Damage

Parking receptacles mounted in high‑traffic areas can be damaged by vehicles or equipment. Install receptacles in protected locations or use protective covers when not in use.

Field Notes

Troubleshooting Guide

Corrosion Preventing Plug Removal
Likely Cause
The parking receptacle has corroded due to exposure in an aggressive environment, seizing the threads.
Diagnostic Steps
Inspect the receptacle threads and body for corrosion product; attempt removal by hand before applying tools.
Corrective Action
Apply penetrating/anti-seize compound as appropriate and carefully work the plug free; replace the receptacle with a corrosion-resistant (stainless steel or brass) unit if damage is significant.
Difficulty Mating the Plug (Cross-Threading)
Likely Cause
The plug was cross-threaded during a previous connection, damaging the receptacle threads.
Diagnostic Steps
Inspect threads on both plug and receptacle for visible damage or misalignment before attempting to mate.
Corrective Action
Replace the damaged receptacle, and ensure future connections are started by hand before torquing to prevent recurrence.
Moisture or Contaminant Ingress at a Parked Plug
Likely Cause
The plug was not tightened to the specified torque in the parking receptacle, leaving an incomplete seal.
Diagnostic Steps
Check the plug's seating and torque against the manufacturer's specified value using a torque wrench.
Corrective Action
Re-torque to spec, or replace the plug/receptacle if seal damage has already allowed moisture ingress.
Plug Left Dangling or Placed on the Ground
Likely Cause
No parking receptacle is installed at this maintenance point, or the existing one is inaccessible.
Diagnostic Steps
Confirm whether an adequate parking receptacle exists at this location per the site's maintenance point layout.
Corrective Action
Install an additional parking receptacle at the maintenance point to ensure plugs are always properly stored when disconnected.
Wrong Plug Type Mated to Receptacle
Likely Cause
A mismatched connector type (e.g., a secondary plug on an L-823 receptacle) was used, compromising the seal.
Diagnostic Steps
Verify the plug type against the receptacle's rated type and identification marking.
Corrective Action
Replace with the correct matching plug type, and improve identification/colour-coding at the location to prevent recurrence.
Reliability

Failure Modes & Root Causes

Receptacle Corrosion / Thread Seizure
Medium Severity
Root Cause
Prolonged exposure to an aggressive environment corroding the receptacle body or threads.
Effect
The parked plug becomes difficult or impossible to remove without tools, risking thread damage during removal.
Detection Method
Inspection of receptacle threads and body for corrosion product during scheduled maintenance.
Cross-Threaded Coupling
Medium Severity
Root Cause
The plug's coupling ring was started off-axis and forced rather than threaded by hand before torquing.
Effect
Damaged threads that prevent a clean, sealed mate on future connections, including with an active cable plug.
Detection Method
Visual inspection of threads for damage or misalignment before attempting to mate a plug.
Incomplete Torque / Seal Failure
Medium Severity
Root Cause
The plug was not tightened to the manufacturer's specified torque when parked.
Effect
Incomplete seal allows moisture and contaminants to enter the plug while it sits idle.
Detection Method
Torque wrench check of the plug's seating against the manufacturer's specified value.
Missing or Inadequate Receptacle Provision
Low Severity
Root Cause
No parking receptacle was installed at a given maintenance point, or the installed one is inaccessible.
Effect
Plugs are left dangling, unprotected, or placed on the ground, leading to contact damage and dirt ingress.
Detection Method
Confirmation of receptacle provision against the site's maintenance point layout during a site survey.
Wrong Receptacle Type Fitted
Low Severity
Root Cause
A receptacle type mismatched to the expected plug family (e.g. a secondary receptacle used for an L-823 plug) was installed.
Effect
Proper sealing and protection is not achieved even when a plug is parked and torqued correctly.
Detection Method
Verification of receptacle type against its identification marking and the plug family it is meant to serve.
Mechanical Impact Damage
Medium Severity
Root Cause
A parking receptacle sited in a high-traffic area is struck by a vehicle or ground equipment.
Effect
Physical damage to the receptacle body or threads that compromises its ability to seal a parked plug.
Detection Method
Visual inspection following any known vehicle contact, and periodic condition checks in high-traffic locations.
Precautions

Safety & Operational Notes

Verify De-Energised Before Handling a Parked Plug
Electrical Safety

Confirm with a meter that a plug parked in the receptacle is genuinely isolated before handling its pins; do not assume a stored plug is dead without checking, particularly on circuits that may have been re-energised since it was disconnected.

Keep Receptacles Capped
Environmental Sealing

Always fit a dummy plug or protective cap in an unused receptacle; an open receptacle allows moisture and contamination that degrades the pins and compromises the connector's performance when next used.

Positive Circuit Identification
Compliance

Label parked plugs and their receptacles clearly to avoid a mis-connection when equipment is later reconnected, since a wrongly matched connector can cross-feed circuits or leave a fixture on the wrong loop.

Standing Water in Pits & Handholes
Electrical Safety

Where the receptacle is located in a below-grade pit or handhole, treat any standing water as potentially energised until isolation is confirmed, and drain before reaching in.

FOD Control
Operational

Account for caps, plugs, and fasteners while a pit or handhole is open, and secure the site before leaving it unattended.

PPE
Personnel Safety

Use insulated tools when handling connectors on any circuit that has not been positively verified as isolated, and appropriate PPE for below-grade access.

Field Insight

Engineering & Expert Notes

An Empty Receptacle Still Needs Its Own Sealing Cap
Sealing

A parking receptacle left uncapped between uses is exposed to the same contamination risk as an unprotected plug; always fit the receptacle's own protective cap or dummy plug when it's not actively holding a stored connector.

Check Contact Condition Inside the Receptacle, Not Just the Housing
Corrosion

The receptacle housing can look intact while internal contacts have started to corrode from trapped moisture; periodically inspect and clean the internal contact surfaces, not just the visible exterior.

Mounting Position Affects How Well the Receptacle Actually Gets Used
Installation

A parking receptacle mounted somewhere inconvenient for the maintenance crew tends to get bypassed in favour of leaving a disconnected plug lying unprotected nearby. Position receptacles where they're genuinely easy to use during routine disconnect work, not just where mounting was structurally convenient.

Make Parking the Plug Part of the Disconnection Procedure, Not an Afterthought
Process

The receptacle only protects a connector if it's actually used every time; build 'park the plug' into the standard disconnection checklist rather than treating it as optional good practice.

Confirm a Parked Plug Is Genuinely De-Energised, Not Just Disconnected
Electrical Safety

A plug sitting in a parking receptacle can still be connected to an energised source on its other end if the disconnection was only partial; verify zero energy before handling a parked plug, don't assume storage implies isolation.

UV and Weather Exposure Age an Outdoor Receptacle Faster Than Its Rating Suggests
Durability

Receptacles mounted in fully exposed outdoor locations can see their seals and cap gaskets degrade faster than a general weatherproofing rating implies; include cap and gasket condition specifically in scheduled inspections at exposed locations.

Quick Answers

Frequently Asked Questions

Short answers about connector storage (parking) receptacles: purpose, use, torque, standards and maintenance.

Q1What is a connector storage or parking receptacle?

It is a mounting socket, also called a storage socket or dummy receptacle, that receives and protects an L-823 primary or secondary plug when that plug is disconnected from its equipment receptacle.

Q2Where are parking receptacles installed?

Inside or on junction boxes, on some isolating transformer housings, on distribution panels and CCR enclosures, at test points and disconnect panels, and inside equipment shelters.

Q3How does a parking receptacle protect the plug?

Its threaded shell engages the plug's coupling ring and compresses the plug's O-rings for a watertight seal. Its socket contacts or blank inserts receive the pins, protecting them and keeping the contact surfaces clean.

Q4What torque should be used on a parking receptacle?

The page gives 3.5 to 5.5 N·m for L-823 connectors and 2.5 to 4.0 N·m for secondary connectors. Always follow the manufacturer's specification for the actual part.

Q5What is the difference between a parking receptacle and a dummy plug?

A parking receptacle stores a disconnected plug, while a dummy plug caps an unused receptacle. Both keep connector parts sealed and clean when they are not in service.

Q6Which standards apply to parking receptacles?

The main references are FAA AC 150/5345-26 (L-823 plug and receptacle connectors), IEC 63067 (connecting devices, general requirements and tests) and ICAO Annex 14.

Q7How often should parking receptacles be inspected?

Annually. Check that the receptacle is present and torqued, the threads are free of cross-threading damage, and the body shows no corrosion, especially in humid or coastal environments.

Q8What are the common problems with parking receptacles?

Missing receptacles that leave plugs dangling unprotected, cross-threading, insufficient torque that lets moisture in, corrosion, and using a receptacle that does not match the plug type.

Explore Further

Related Components

Go Further

Go Beyond the Component. Understand the Complete AGL System.

You have explored the component. Now understand how it works within the complete Airfield Ground Lighting system.

Learn AGL from fundamentals to design, installation, testing, photometry, commissioning, maintenance and troubleshooting through structured technical training at Precision AGL Academy.

Build practical knowledge. Understand the circuit. Read the standards. Troubleshoot with confidence.

Your next step in AGL starts here.

The Learning Pathway
Learn Understand Design Test Maintain Document Apply Certify

Need expert guidance on connector storage and protection for your AGL installation?

Precision AGL Academy provides advice on parking receptacle placement, maintenance, and best practices for protecting AGL connectors.