How is a connector selected?
Four decisions, taken in order, that narrow the choice to the right sealed connector or joint for a series circuit.
Connectors are made on site and are the usual weak point of a circuit, so the right one matters. The side of the transformer sets the duty, since a primary connector carries the full loop current and a secondary connector serves one fitting. Whether it must be plugged and unplugged sets the type, it must match the cable and circuit rating, and the location decides how it is sealed.
The flowchart only narrows the choice. The final connector is confirmed against the design for type and keying, rating, cable fit and seal or kit, and against the standard it must meet.
Frequently Asked Questions
Q1How is an AGL connector selected?
By working through a few decisions in order: which side of the isolating transformer it joins, whether the joint must be plugged and unplugged or made permanent, what cable and circuit rating it must match, and where it will sit. The result is then checked against the data sheet and standard.
Q2Why does it matter whether a connector is primary or secondary?
A primary connector is part of the series loop and carries the full circuit current, so a poor one can affect every light on the circuit. A secondary connector is on the isolated side and serves one fitting, so the usual effect is one dim or dark light. Each must be rated for its own side.
Q3When is a plug-in connector used and when a permanent joint?
A plug-in connector lets a transformer, fitting or sign be disconnected, tested or replaced without re-jointing the cable. A permanent in-line joint joins two lengths of cable where no disconnection is needed. The design and the manufacturer’s instructions decide which is used where.
Q4What must a connector match?
The cable or lead it is made onto, in conductor size, insulation and jacket, and the circuit it serves, in voltage and current rating, such as the 5 kV class of primary series cable or the lower-voltage class of secondary cable. It should also be keyed to mate one way and be compatible with the part it mates to, which the manufacturer confirms.
Q5What should be checked before the choice is final?
That the type, keying and rating match the design, that it fits the cable or lead, that the seal or kit suits the location, and that the connector meets the applicable standard. The manufacturer’s data sheet and the standard decide, and the finished joint is inspected and tested.
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