Heidenhain
HEIDENHAIN CORPORATION announces EnDat 3, a new
version of its popular absolute position encoder interface. The new EnDat 3
interface has all the benefits of previous versions, but is even faster and
more robust, with simplified functional safety features.
EnDat
3 uses a 200 kHz clock frequency, compared to the 16 kHz of previous versions,
and has doubled its supported bandwidth, from 12.5 to a 25 Mb/s. This means
that data can be transferred much more quickly.
HEIDENHAIN
has simplified functional safety aspects of the interface, and EnDat 3 now
leverages the industry standard for functional safety: black channel. This
makes implementation much easier for OEMs.
Milton
Willis, Machine Tool Product Specialist at HEIDENHAIN, says: “We’ve listened to
feedback from machine tool manufacturers and their end users, as well as OEMs,
and have responded by making EnDat 3 faster, more robust, and more
fully-featured than any competitive product.”
The
EnDat 3 interface detects its absolute position, rather than just its position
relative to a reference. This is a big advantage when a machine starts up, as
it does not require any machine movement to establish its position – which can
be extremely time-consuming for large machines. EnDat 3, therefore, enables
faster startup, which means more throughput.
The
new encoder interface has reduced cabling requirements compared to the previous
version, going down to a two or four-wire setup as opposed to the eight wires
previously needed. This reduces cabling requirements and hence cost, which is a
significant benefit in the machine tool and robotics sector. For robotics
applications, the EnDat 3 also offers bus operation, which allows manufacturers
to daisy-chain encoders together, to reduce cabling and therefore reduce costs,
as well as to simplify design and manufacturing.
EnDat
3 has increased memory and storage capacity and offers the ability to
password-protect information that is stored in the encoder. For example, this
could be specific code or machine information to which the company or manager
might not want to allow full access for operators.
The
new interface supports an increased number of temperature sensors, to monitor
temperatures anywhere, from a robotics arm to inside a cabinet. It has also
added support for multi-dimensional encoders, which enables easier installation
and simplifies the downstream calculation that’s involved with using multiple
reader heads on a single cable.
Like
all the versions of EnDat, the new EnDat 3 is bi-directional, so it can support
monitoring and diagnostics. This means it can be used for preventative
maintenance, for example alerting the CNC when a fault is detected.
The first commercial version of the interface, EnDat 2.1, was created in 1995. At that time, most encoders used analog or digital incremental interfaces. EnDat 2.1 used an RS-485 output signal, which is more robust and less susceptible to noise.