06/11/06 - Article - System Expansion: A matter of principle
Consistently efficient: This is the motto that describes the whole AS-Interface approach. And so when it comes to development or enhancement of system components, there are clear rules: Advancements that are not simple and economical enough to use in actual application are unlikely to receive AS-i certification. Bihl+Wiedemann had no difficulty here: Their new double master makes it possible for the first time to operate two AS-i networks using just a single power supply. |
Less is more: With this as
the guiding principle AS-Interface has in a short time established itself as
the standard on the primary automation level. The simple idea of replacing
cumbersome parallel wiring of sensors and actuators with a robust but
straightforward field bus network has changed manufacturing concepts at
productions facilities all over the world.
Millions of
kilometers of cable have been saved already thanks to the new system, which
replaces the traditional cable harnesses. Now up to 62 slaves can be operated
on a single AS-i branch, all directed by one master. Which adds up to welcome
benefits for the user, since less material means simpler installation and
significantly lowered costs.
No wonder
then that the trend towards minimalization was carried even farther. Along with
growing proliferation of the new technology, AS-i networks found application in
increasingly complex systems. And as a consequence, the need to include more
than 62 data collectors on the sensor/actuator level was seen with greater
frequency. The development of the so-called double master thus represents a new
milestone: Suddenly the purchase and installation of an additional master was
no longer necessary when a second AS-Interface was added, thereby reducing the
cost differential between single and multiple networks. Because even though the
number of installed slaves doubles compared with a single master, the cost
increases by only about a third.
 
How the new concept can in fact be implemented is shown in the new double masters from Bihl+Wiedemann: These incorporate their own data decoupling unit, so that only a single 30V power supply is needed for two AS-i networks. The advantages for the user are obvious and can be quantified not just in dollars and cents, but also in days, weeks and cubic meters. Because in addition to up-front investment costs, the new master concept saves installation effort and space in the control cabinet. But the benefits don't stop there: With the AS-i power supply decoupler from the same manufacturer any number of double masters can be operated without an integrated data decoupling unit using just a single power supply. In certain configurations this allows up to four double masters with up to eight AS-i networks to be powered by one 30V power supply. |
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