SN EZ-Flip Connector

What the SN EZ-Flip connector is

The SN EZ-Flip connector is a polarity-changeable SN duplex connector. The manufacturer describes it as a duplex Base-2 connector. In plain terms it is an SN pair whose transmit and receive positions can be swapped after the connector has been built, so a link wired the wrong way round can be corrected without cutting the cord or throwing it away. It belongs to the SN connector family and shares that family's loss and return loss figures.

Polarity is the commonest cause of a link that is built, tested for loss and yet will not come up. The fibre is fine, the connectors are clean, and the transmitter is talking to the transmitter. A plug that can be flipped removes that whole class of fault from the stock list.

Radix can supply the EZ-Flip plug loose, or built into patch cords and cable assemblies to your drawing. The part is and quoted by form, phone or WhatsApp from Pune.

Why polarity goes wrong in duplex links

A duplex link has two fibres. At each end, one is the transmit side and the other is the receive side. For a link to work, the transmit fibre at one end must reach the receive port at the other. Over a single cord this is automatic if the cord is a cross. With patch panels in the middle, there are several cords and adapters in a chain, and the number of crossovers across all of them must be odd. It is easy to build a chain with an even number.

Different sites choose different methods: build every cord straight and let the panel cross, build crossed cords, or cross at a cassette. Each method is sound, but mixing them gives faults. The same problem exists in multi-fibre systems, as shown in the MPO polarity guide.

A flippable plug turns a wrong build into a quick job: swap the pair, retest, and carry on. The polarity testing guide explains how to confirm the result.

Figures and what is shared with the SN family

A changeable-polarity design must still keep the ferrule pair aligned after a flip, so ask for the data sheet to see what, if any, loss change is stated for a flipped connector. Do not assume that a flipped plug and a fresh one are identical until the figure is in front of you. After any flip, clean, inspect and test the link as you would a new one.

How to use the flip step safely

1. Remove the plug from the adapter, holding the housing and not the cable.
2. Cap or clean the end faces while the plug is out. Depending on the design, a flip step can bring the ferrules into contact with fingers or tools, and that is when dust gets on them.
3. Follow the flip procedure on the manufacturer data sheet or the instructions that come with the plug. The method and the tool, if any, differ between connector designs.
4. Refit the plug and confirm that it latches.
5. Test the link for loss and for polarity, and record the change.

Never flip a plug in a live link, and never flip it with a bare fingertip on the ferrule. Keep the cord strain-free during the step, since the cable should not twist as the connector turns. The inspection method is in the end face cleaning and inspection guide.

When a changeable plug is worth having

• Large installs where cords of mixed polarity are patched by many hands.
• Stock-holding sites that want one cord type that fits every method.
• Projects where the polarity method is not final when the cords are ordered.
• Test and lab work, where links are re-patched between setups.
• Upgrades, where an old panel uses one method and the new equipment expects another.

It is of less value where a design is fixed and documented, since a fixed plug is simpler. A changeable connector is a flexible part, and flexibility has a small cost: another moving feature that could be mishandled. Use it where the benefit is real.

EZ-Flip next to the other SN plugs

The CS family has its own changeable plug, described on the CS EZ-Flip connector page, for those who work with the CS duplex format. The two are not interchangeable, because the housings are different.

Recording a flip

A plug that can change polarity also needs a record of what it is set to. If nobody writes the state down, the next engineer cannot know whether a cord is straight or crossed without testing it. Use a small flag or a colour mark on the cord near the plug, or keep a port list, and update it at every flip. The labelling and documentation guide suggests fields that are worth keeping.

For acceptance, test polarity at the end of the build as well as loss. A visual fault locator or a light source at one end and a meter at the other shows at once whether the pair is crossed the way the drawing says. Do this before the equipment is attached, so the first power-up is not also the first polarity check.

Worked example: standardising a stock cord

Assumed values: a site buys 200 SN duplex jumpers a year for three different projects, two that use a straight method and one that uses a crossed method. Under fixed polarity, the buyer must hold two kinds of cord and label them well.

1. Switch to EZ-Flip jumpers for all 200. One part number, one label type.
2. On each project, set the polarity at install and record it in the port map.
3. If a link fails a polarity test, flip one end, retest, and log the change.
4. At the year's end, compare the number of cords flipped with the number held. If the count is low, the benefit is the stock simplification, not the flips.

These numbers are assumed for illustration. The aim is to show what is being traded: a slightly more complex plug against a simpler stock list.

Buyer checklist

• Whether polarity really needs to be changeable, or can be fixed on the drawing.
• Cord type and cable: round 1.6 mm or 2.0 mm, Uniboot or other, as the data sheet allows.
• Fibre type, grade, polish and loss grade.
• Length and tolerance for each cord.
• Boot colour and marking, so that a flipped cord is still recognisable.
• The flip procedure and any tool, as stated on the manufacturer data sheet.
• Quantity and spare allowance.

What to send Radix to quote it

Send the cord drawing or list, the fibre details and the quantity, and say that a changeable plug is wanted. If cords are built, Radix tests each cord before dispatch. Use request a quote, or send the details by phone or WhatsApp. The RFQ guide lists useful fields, and the fibre optic patch cords page describes the cord formats we build.

When this is not the right part

• The polarity is fixed in the design and documented.
• The jumper will be handled by people with no training in the flip step.
• You need a very short body for behind-the-wall use.
• The connectors are in a harsh outdoor setting. The IP series is built for that.
• Your equipment uses LC or CS ports.

The connector hub lists the other duplex formats.