Karel DS200, Technical Reference And Installation Manual

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DS Series PBX Technical Reference And Installation Guide
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VI.3.A.1. THE DCC CHASSIS
The DCC chassis is a 19”, 6U-high box, which has been formed of an aluminum cage
structure and which mechanically places the entire cards in contact.
It has slots for 17 cards inside, which is composed of plastic rails that are at the top and
bottom of the slot.
Lower and upper covers have been designed to allow air circulation in the DCC block. The
air vents on those covers have been designed according to EMC (electromagnetic
compatibility) and EMI (electromagnetic interference) rules.
The aluminum card covers has a special lock mechanism. On each of the lower and upper
sections of the card covers, there is a screw and special-purpose plastic holders. Those
holders allows cards to be plugged in firmly when they are pushed into the chassis, whereas
they facilitate removing cards and allows them to be pulled out without jerking. Cards are
completely fixed in their positions in the chassis by tightening the screws that are on the
lower and upper sections of the card cover.
Each card cover has connector spaces that allow the card to be connected to other units. By
this way, the entire cabling of the DCC block, which has been placed in the 19” cabinet, can
easily be done through the front face.
The chassis has no front cover. Each card that is to be placed in the chassis has an
aluminum card cover on one edge, thus, those card covers form a front cover when the cards
are plugged in side by side. Lighted indicators on the front face supply various pieces of
information to technical personnel.
VI.3.A.2. THE DCC BACKPLANE
Communication of the entire electronic units in the DCC block is made over the DCC
backplane. The DCC backplane is the card that constitutes the electronic framework of the
DCC block. The DCC backplane transfers all signals used by DCC cards to pertinent card
slots and it distributes the power coming from the DCC Power In card to all card slots. The
DCC backplane is the card that forms the electronic skeleton of the DCC block.
There are 2 special slots for the DCC Utility card and one special slot for the DCC Power In
card on the backplane, as well as 14 slots for DCC 8E1 Interface cards.
VI.3.A.3. THE DCC POWER IN CARD
Definition:
The DCC Power In card regulates the -48V DC feed voltage it receives from the power block
of the DS200L system and transfers it to the backplane.
The Power Control Card controls the -48V DC voltage fed to the DCC unit and minimizes
surges in voltage with fuses and regulators on it. The card also generates the reference
signal for the backplane, which is 1.5V DC.