Relay Contact; Backbone - Procentec ProfiHub B2FOR+ User Manual

2.6 Relay contact

The ProfiHub features a potential-free relay contact. This alarm contact can be used to monitor the power
supplies. Example applications are: Connect a LED tower, alarm buzzer, SMS server or use it as a digital signal
for the PLC. The relay can also be used for alarming in case of retries, illegals, or other events. For more
information refer to Chapter 3.
If only one power supply is used, the alarm contact is closed after 60 seconds after start-up. If two power
sources are connected, the contact is open. When one of the power supplies fails for 3 seconds or more, the
contact will close and the Power Indicator LED will blink. If you are using only one power source and wish to
use the Relay contact, simply connect Power 1 to Power 2.
In the case of an interrupted power supply you can reset the contact by pressing the 'Reset' button. The
contact will open and the LEDs will stop blinking.
The Alarm contact is also switched when the ProfiHub is in Redundant mode and one of the redundant paths
fails, or when the fiber ring fails or one of the fiber signals is low or off.
The maximum power to be connected to the alarm contact is 24 VDC. The maximum current consumption is
500 mA.
It is advised to use a Limited Power Source (LPS) of NEC Class 2 or CEC Class 2 for powering the alarm contact.

2.7 Backbone

The fiber channel can be used to create a backbone together with a ComBricks set. The ComBricks can retrieve
all the diagnostic information (a ComBricks FOR-MM1 or FOR-SM1 is required). It is also possible to connect the
ComBricks via copper to one of the copper channels of the ProfiHub B2FOR+ or B4FOR+.
ProfiHub B4FOR+
Fig. 13 - Example topology for a fiber backbone with ProfiHubs
ProfiHub B2FOR+ / B4FOR+ User Manual | August 2019 | © PROCENTEC 19/60