Installation, Operation and Maintenance Manual
MAN712 Rev. 9
June 2021
Working Principle and Detailed Description
Section 5: Working Principle and Detailed Description
33
The ELBS-20 monitors the status of the External Power Supply (on each single DC/DC
converter) and the status of the Battery Packs Power Supply (see Section 5.2.2) and
automatically applies the below limitations according with these statuses, on the SOV
Control Outputs that are used during the Safety Action:
•
External Power present (both DC/DC converter OK): no limitations
(enabled SOV Outputs).
•
External Power present (only one DC/DC converter OK): SVC1, RL1, SVC1+RL1
or RL1+RL2 (*).
•
D Auxiliary Battery Packs (both OK): no limitations (enabled SOV Outputs).
•
Only one Battery Pack OK: SVC1, RL1, SVC1+RL1 or RL1+RL2 (*).
•
One External Power Supply OK + one Battery Pack OK: SVC1, RL1, SVC1+RL1
or RL1+RL2 (*).
(*) Case 1: if SVC1+SVC2 are enabled only SVC1 is used during the Safety Action.
(*) Case 2: if SVC1+SVC2+RL1 are enabled only SVC1+RL1 are used during the
Safety Action.
(*) Case 3: if SVC1+RL1+RL2 are enabled only SVC1+RL1 are used during the Safety Action.
(*) Case 4: if SVC1+SVC2+RL1+RL2 are enabled only SVC1+RL1 are used during the
Safety Action.
The selected SOV Control Outputs work in the following way during the Safety Action:
•
RL1 and RL2: the coil is energized and the relay contacts commutate
(NO-C = short circuit, NC-C = open circuit).
•
SVC1 and SVC2: a 24 V DC (max.100 mA) is generated as output.
At the end of the Safety Action (its length is determined by the “Duration” parameter) RL1,
RL2, SVC1 and SVC2 return to their original status:
•
RL1 and RL2: the coil is not energized (NO-C = open circuit, NC-C = short circuit).
•
SVC1 and SVC2: 0 V output.
The ELBS-20 provides also the possibility to use DO1 and DO2 as SOVs Control Outputs
when they are set as “SOV Control” (see
Section 6.2 for details).
