Ground-breaking smart encoders from ifm electronic
New incremental encoders from ifm electronic truly break the mould: not only are they programmable, they have switched outputs for a pre-set count or speed but the real innovation is the built-in display of, for example, count or speed.
A common application of incremental encoders is length measurement or distance travelled by a device, with the encoder attached to a measuring wheel for this purpose and the encoder providing a pulse train. Commonly this is then counted and, for example, the product cut or the vehicle stopped at a specific count. With the new encoders from ifm, there is no need to use an external counter of counting function in the PLC. The encoder can carry out this function and release a simple signal when the required count is reached. Not only does this save on hardware (or PLC programming and runtime) it also avoids miscounts. A fast input card is simply not needed. IO-Link is supported by the main PLC manufacturers as well as by other device suppliers, so users would not be left ‘high and dry’, although an IO-Link device operates as a standard device if there is no IO-Link on the control side. Future-oriented technology it may be, while being firmly grounded in the present.
Another common use of pulse trains from devices such as incremental encoders is the monitoring of a machine speed. Whether the pulse train is from a rotating device or maybe even a reciprocating movement, the rate of pulses has to be compared to a pre-set value in order that the system can monitor for an increase or decrease in the speed. Now the new encoders from ifm will carry out that very function, if selected, again relieving the PLC of the responsibility.
Easy programming: setting the resolution and the many other functions is simply done using the intuitive pushbuttons on the encoder. Of course remote setting is also possible, and for this ifm electronic chose the IO-Link open standard, so the user is not tied to proprietary software but can instead use standard PLC’s or HMI’s because IO-Link is supported by major manufacturers.
IO-Link is rapidly establishing itself as the default standard, because it offers so many advantages and is suited to a wide variety of applications. IO-Link is described under Part 9 of the international IEC61131 standard for PLC’s, defining the protocol for bidirectional transmission of data between a three-wire sensor and higher level systems. IO-Link is offered by over one hundred manufacturers of sensors, actuators, PLC’s and ancillary equipment, and one of the founding companies with the largest range of products is ifm electronic – not only does ifm already have several hundred article types with IO-Link built in, there are already over four million of them in the field.
Using such an interface means that whatever the device it can be accessed remotely, be that for parameter storage or resetting. Parameter storage externally has advantages for machine builders and users alike. Builders can easily repeat a step in the construction of a machine with a simple upload of one parameter set. Users can also make use of this facility in the event of failure or damage. However, probably of greater benefit to the end user is the remote setting of parameters and functions. Flexibility and agility in manufacturing are quoted as being part-and-parcel of the move to more efficient manufacturing; so should it be necessary to change a manufacturing process ‘mid-stream’ then the ability to simply transmit to all IO-Link devices at the push of a button will become indispensable.
Stock reduction is a major advantage with the new encoders: machine builders and incremental encoder users can now select the housing they require, choosing 6mm or 10mm diameter solid shafts, or 12mm semi-hollow, and that is all they need to stock, programming the resolution as required. In addition to selecting the resolution on the device, these smart encoders also offer selectable 5V or 24V outputs.
The new incremental encoders from ifm use the latest of technologies for sensing as well as the interface connection, and physically that connection is simple, too. Our customers tell us they do not like M23 connectors, so the new range is equipped with the more compact M12, which also rotates to select the cable angle. IO-Link uses standard M12 connections and wiring. There is no requirement for screened cables with the new encoder range. Of course, for those who feel that the new functions and display are not for them, there are basic versions without the interface, and fitted with a 2m cable.
Anyone using incremental encoders up to a resolution of 9,999 steps (or ‘counts per turn’) would be wise to take a closer look at these units. It certainly would not harm to ask for a trial sample!
Versatility and robustness are the hallmarks of these encoders from ifm electronic. Not only is the technology ground breaking, but ifm electronic believes the pricing is, too. Now that’s true innovation!
ifm is committed to working closely with its customers to develop products which precisely match their needs, and the company provides expert, readily accessible technical support to help users maximise the benefits they gain from ifm products.
For further information, contact Gemma Anderson, ifm electronic Ltd., efector House, Kingsway Business Park, Oldfield Road, Hampton, Middlesex, TW12 2HD. Telephone: 020 8213-0000. E-mail – gemma.anderson@ifm.com.
