What is connector sealing?
Closing a connector or joint against water, so the conductor and its insulation stay dry for the life of the circuit. A connector is only as good as its seal, and the seal is made during installation, not later.
Connectors and joints sit in base cans, pits and the ground, where water is a constant risk. If moisture reaches the conductor, insulation resistance falls and the circuit can develop an earth fault or open. In a series circuit an open on the primary side puts every light on the loop out, and a primary earth fault raises an alarm and can shut the regulator down, while a fault on the secondary side usually affects one light. The seal is the part that keeps water out, and it is best made right the first time, because a faulty seal means opening the joint and remaking it.
1Make it safe, then keep it clean and dry
Isolate and lock out the circuit and prove it dead before work, as your site procedure requires. Then keep the parts clean and dry: cable ends, mating faces and the sealing parts. Shelter the work from rain and groundwater. Moisture or dirt trapped inside a seal stays there.
2Mate fully, then seal as the maker instructs
Seat the connection fully, keyed and locked as the connector requires. Then fit the seal the manufacturer specifies, such as a moulded boot, sealing sleeve, shrink sleeve or approved tape, so it overlaps and grips the cable jacket at both ends. Follow the kit instructions for cleaning, heat or cure time and orientation. Do not improvise with tape or sealant not approved for the connector, and do not leave strain on the cable that can pull the seal open later.
- Clean and dry every part first
- Seat the connection fully
- Seal over the jacket at both ends
- Seal damp or dirty parts
- Use unapproved tape or sealant
- Leave strain on the cable at the seal
3Check, test and record
Look over the finished seal for gaps, voids, wrinkles and damage. Test insulation resistance as the commissioning or maintenance plan requires before the connector is buried or the can is closed, discharge the circuit afterwards, and record its location and the readings. A seal found faulty now costs minutes; found later, it costs a dug-up circuit.
| Item | What to do |
|---|---|
| Cable ends and jacket | Clean and dry; free of cuts and damage |
| Mating faces | Clean and dry; seat fully and lock as required |
| Seal type | Moulded boot, sealing or shrink sleeve, as the maker specifies |
| Seal coverage | Overlaps and grips the jacket at both ends |
| Cable strain | None at the seal; support the cable so it does not pull |
| Conditions | Shelter from rain and groundwater while sealing |
| Test | Insulation resistance before burying or closing the can |
| Record | Location, readings, date |
Frequently Asked Questions
Q1Why must AGL connectors be sealed?
Most connectors sit in base cans, pits or the ground, where water is a constant risk. Moisture in a connector lowers its insulation resistance and can cause an earth fault or an open circuit. In a series circuit an open on the primary side puts every light on the loop out, and a primary earth fault raises an alarm and can shut the regulator down, while a secondary-side fault usually affects one light.
Q2How is a connector sealed?
By following the connector or kit manufacturer’s instructions: clean and dry parts, a fully seated connection, and the approved seal, such as a moulded boot, sealing sleeve or shrink sleeve, fitted so it grips the cable jacket at both ends.
Q3Can a connector be sealed in wet conditions?
Not reliably. Moisture trapped during assembly stays inside the seal. Keep the parts clean and dry, shelter the work and wait or dry the area as the manufacturer’s instructions allow.
Q4What goes wrong with a connector seal?
Common causes are a damp or dirty mating face, a connector not fully seated, a damaged or misplaced seal, a void or gap at the end of the sleeve, and strain on the cable that pulls the seal open later.
Q5What should be done after sealing a connector?
Check the seal by eye, test insulation resistance as the commissioning or maintenance plan requires before the connector is buried or the can closed, discharge the circuit afterwards, and record the connector’s location and the readings.
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