ABB RELION 670 Series Technical Manual page 1287

1MRK 502 066-UUS B
For communication with high speed modules, e.g. analog input modules and high speed serial
interfaces, the NUM is equipped with a Compact PCI bus. The NUM is the compact PCI system card
i.e. it controls bus mastering, clock distribution and receives interrupts.
22.2.2.2 Functionality
The NUM, Numeric processing module is a high performance, compact-PCI CPU module. It is 6U
high and occupies one slot. Contact with the backplane is via two compact PCI connectors and an
euro connector.
The NUM has one PMC slot (32-bit IEEE P1386.1 compliant) and two PC-MIP slots onto which
mezzanine cards such as SLM or LDCM can be mounted.
To reduce bus loading of the compact PCI bus in the backplane the NUM has one internal PCI bus
for internal resources and the PMC/PC-MIP slots and external PCI accesses through the backplane
are buffered in a PCI/PCI bridge.
The application code and configuration data are stored in flash memory using a flash file system.
The NUM is equipped with a real time clock. It uses a capacitor for power backup of the real time
clock.
No forced cooling is used on this standard module because of the low power dissipation.
Technical manual
Section 22
IED hardware
M12644-3 v3
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