A Guide to Ferrules and Ferruling
Engineers and panel builders can be easily confused by the wide variety of wire marking solutions that are currently available. These range from extremely basic individual ferrules – which can be time-consuming to fit – to high tech machines that produce terminal markers, along with a range of other applications.
While it’s safe to assume that the user would want to have a straightforward, easy-to-work and reliable solution, the ease, straightforwardness and cost-effectiveness of that solution will depend on the complexity of the job in hand.
At Silver Fox, we manufacture a 2-part wire marking systems, the Legend™ 2 part system comes in both thermal and laser printed options. These involve users printing the label, either via our Fox-in-a-Box® Thermal printer or an ordinary laser office printer using our Labacus® Innovator software. The labels have been tested for High/Low Temperature and Salt Mist Spray according to Lloyds Register Type Approval System and are used with clear plastic tubing sleeve that has two recesses – one for the label and one for the wire. The installation of the marking label can take place before or after the sleeve is installed on the wire – and irrespective of whether or not the wire is connected.
An important benefit is that the ident (ID) can be changed without cutting off the wire. So, if this happens during the project, a significant amount of time can be saved by removing the label and replacing it with another one. This takes seconds and compares favourably with the time and cost of having to cut the wire, re-label it, re-terminate it and then possibly even re-test the circuit, which would be necessary when using individual ferrules or a printed tube, such as heat-shrink or non-shrink. Clearly, there are projects where, during construction, there will be many changes – so a 2-part system becomes attractive even though each ID involves two operations (applying the clear tube and then applying the label). However other automated systems, such as heat-shrink or non-shrink, involve only one operation – of sliding a single tube onto the cable/wire
A key disadvantage of using most 2-part wire marking systems is that the plastic on which the label is printed could be rather thick. So, the label might be difficult to fit into its recess in the clear tubing and may also be difficult to get out again. In contrast, Silver Fox’s Legend® 2-part labelling system uses flexible material which, with the use of a special tail, can be pulled into/out of the label recess in the clear tubing. Once the project is finished, the tail end can be removed or cut off. The label can still be changed if needed, however.
With any wire marking job that involves up to, say, four characters, it makes some sense to use manual ferrules. Taking the time to turn on a computer and a printer, load them with both the relevant information and the blank labels – and then produce and apply the labels – is more expensive and time-consuming than using the low-tech, old-fashioned manual ferrule approach.
There are, of course, other approaches to wire marking – notably the heat-shrink and the non-shrink tubing approaches. Both heat-shrink and non-shrink tubing systems are similar in that they’re both tubes to which printing is applied in some form. Heat-shrink polyolefin labels can be shrunk down using a heat gun (and will, thus, grip the cable they’re labelling), while the non-shrink is usually made from PVC and is just slid onto the wire.
Using non-shrink tubing can also be helpful in higher volume jobs particularly where there are expected to be fewer changes but where it’s important to be able to produce the relevant IDs not only cost-effectively but also in good time. The benefits of this approach include:
- Single application – only one tube is slid onto the wire, saving time, whereas by definition, with the 2-part system, there are two parts and, thus, two operations
- Non-shrink tubing is a low-cost option, both compared with individual ferrules and with heat-shrink tubing
However, if a change is needed during construction then the Legend™ 2-part system has the advantage that the wire doesn’t need to be cut in order to make a change. The more changes that are necessary, the more a 2-part system comes into its own.
The Silver Fox Legend™ non-shrink tubing (made in the UK) is soft, matt and oval in shape. The oval shape is designed to give the label maximum grip on the wire. This prevents the tubing from sliding down the wire while, at the same time, allowing the user to turn and leave the message in a position for easy reading, both now and in the future.
Under the Silver Fox system, when producing the ferrules, users can choose the length of label required. This can be anything from 10mm to 110mm – and more, if needed. There’s no limit on the number of characters that can be included on each label.
While those using the Legend™ 2-part wire marking labels can opt to print these via laser or thermal printer, Silver Fox’s non-shrink and heat shrink labels can only be printed via our thermal Fox-in-a-Box® printer. However, this allows users to print two rolls at the same time and, if they’re using the Professional version of the software, produce the cross-ferrules/both ends of the wire at the same time on the same print run. Whether printing both ends at the same time or just printing a straightforward job with two rolls also ensures the optimum use of thermal ribbon. Moreover, this doubles the printing speed. With the Silver Fox solution, the same printer, thermal ribbon and software can be used on the full range Silver Fox thermal labels. There’s no need to change the ribbon type.
Nick Michaelson, Silver Fox’s CEO, commented: “Non-shrink tubing is an extremely cost-effective way of marking wires – certainly for the higher volumes and even for lower volumes. It compares favourably with using individual ferrules and, in most cases, costs less. Notably, though, there are also time savings in using this method of wire marking. The non-shrink tubing’s quicker for Z-type labels, for example. Instead of putting individual characters on a wire one at a time, users can print the complete ID. This saves money and time – key considerations in today’s business world, where you need the most cost-effective and efficient solution for the job at hand. It’s also ideal for hazardous areas where, even assuming it was possible to use a heat gun, an additional permit would be required.”
For more information on our labelling solutions contact firstname.lastname@example.org