Service Module power buses
Permanent 22-39 V unregulated power buses:
BNR/PF for all the SVM functions in nominal and safe modes, except EAIM (using BNR/EAIM) and SVM thermal control heaters (using BNR/CH/PF).
BNR/CU 1 and 2 for PLM avionics and services.
BNR/CH/CU for PLM and European Instruments thermal control.
Permanent 50 V regulated power bus (BRP) for SVM low-level electronic functions and bus couplers (for both SVM and PLM) in nominal and safe modes, as well as for the Payload Module Controller (PMC)
Switched 50 V regulated power buses (BRA 1 and 2) derived from BRP, used for switching of SVM and PMC bus couplers.
The RSJD provides several power buses, and switch-off lines for the satellite management under failure conditions.
The PLM power distribution is mainly ensured by the PDU, which provides lines protected by latching current limiters.
Last update: 21 June 2006