June 2021
Installation, Operation and Maintenance Manual
MAN712 Rev. 9
Section 5: Working Principle and Detailed Description
Working Principle and Detailed Description
28
5.2.1.2
RS232 – RS485 – Bluetooth Ports
The RS232, RS485 and Bluetooth Ports allow configuring and managing the ELBS-20
through the "Biffi Assistant" software tool [1].
These interfaces (when enabled) are always available if the External Power Supply
is applied.
When just the Battery Power Supply is present, it is necessary to wake-up the ELBS-20 by
pressing the ENTER push-button and then the enabled interfaces become available.
For additional details dealing with the RS232, RS485 and Bluetooth Ports see [1].
5.2.2
Power Supply (External – Battery Pack)
The ELBS-20 accepts two different sources of power supplies:
•
External power supply from 19.2 V DC to 57.6 V DC (24 V DC -20% to 48 V DC
to +20%).
•
Battery Pack power supply: 7.2 V DC (lithium batteries).
The two power supplies can be applied one at time or both.
When both the power supplies are present, the Battery Pack works as back up of the
External Power Supply.
5.2.2.1
External Power Supply
The Interfaces Card has a dedicated isolated DC/DC converter that provides the supply for
the Interfaces Card and the Display/Bluetooth Card.
The Process Card has two isolated DC/DC converters that work “in parallel”; one is called
“Default” and the other one is called “Auxiliary”.
The ELBS-20 checks the status of each DC/DC converter (these data are available on the
Configuration-Managing Interfaces) and limits its functionality (during the Safety Action)
according with the status of the DC/DC converters (see Section 5.2.8).
5.2.2.2
Battery Pack Power Supply
The Battery Pack Power Supply must be applied on:
•
CN2 of the Process Card (Default)
•
CN3 of the Process Card (Auxiliary)
The two Battery Packs work “in parallel”. The ELBS-20 automatically checks the status
of each Battery Packs (when they are enabled) twelve times a day and before the Safety
Action and limits the using of the SOV Control Outputs according to the Battery Packs
status (see Section 5.2.8).
The Battery Packs values are read through a dedicated circuit. The values shown are the
voltages read on the Process Card “after” the diodes (on the Process Card and Battery
Pack Card). The drop of the diodes can be considered approximately 0.65 volts.
An Automatic Battery Check is performed every two hours and before the execution of
the Safety Action. It is also available a command to perform a Manual Battery Check
(see Section 6 for details).
The ELBS-20 limits its functionality (during the Safety Action) according with the status of
the Battery Packs (see Section 5.2.8).
