Karel DS200, Technical Reference And Installation Manual

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IV.1.B. THE DC/DC POWER SUPPLY - SPS248
Definition:
It is the power supply that generates voltages and the ringer signal, which are required for
the system, from - 56 VDC it receives from SPS200.
The figure below shows the appearance of the SPS248 DC/DC Power Supply.
The SPS248 DC/DC Power Supply converts the -56 VDC output of the SPS200 AC/DC
Power Supply to the voltage levels of +5 VDC, -5 VDC and -48 VDC that are required for
system operation. Besides, there is a ringer transformer on SPS248 for generating ringer
signal (67 Vrms.)
Technical Information:
The SPS248 DC/DC Power Supply is plugged into the 64-pin power connector that is on the
BPL200-SPS backplane and it is fixed to the upper front part of the metal rack with a screw.
The SPS248 DC/DC Power Supply contains a metal power rack onto which the SPS248CR
Power Card and the ringer transformer are connected.
Outputs of SPS248CR and the ringer transformer are transferred to the BPL200-SPS
backplane over the 64-pin power connector. The backplane carries these outputs to the
BPL200-MAIN / BPL200-AUX sections. Pin-outs for the SPS248 connector on the BPL200-
SPS backplane are as follows: