Modular fieldbus power supply system

Paul Boughton
R STAHL has expanded the ISbus range, adding a new modular Fieldbus Power Supply System which provides up to 28 V and 500 mA for FOUNDATION fieldbus H1 segments, and also allows for redundant supply.

In 'Boost' mode, a parallel connection of two power supplies enables users to continuously supply the bus with up to 1 A, thus providing sufficient power reserves even for special fieldbus applications.

An integrated Basic Diagnosis function monitors each segment for line faults, reporting these via a potential-free relay contact and indicating them via a red ERROR LED. Likewise, the activation of the integrated switchable fieldbus terminator is clearly indicated by a yellow LED.

The units can be installed on a DIN rail or clicked into place on special bus-Carriers. On each bus-Carrier, up to eight segments with a standard supply or four segments with a redundant supply are connected to a host via optional precon-figured system cables.

The bus-Carrier can be operated with a redundant auxiliary power supply. It ensures the shielded connection of the fieldbus cables via large-scale terminals. The terminals also serve as a cable strain relief. The basic Fieldbus Power Supply version monitors the bus for cable breaks and short circuits.

The Advanced Fieldbus Power Supply, which will be available shortly, additionally provides advanced diagnostic features concerning physical layer parameters such as signal level, noise, asymmetries and jitter, thus rendering costly diagnosis modules unnecessary.

For more information, visit www.stahl.de