Karel MS128, Installation & Maintenance Manual

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Karel MS128 Installation & Maintenance Guide
Edition 3.2
8
SPS128 Power Supply Module consists of a metal power rack, to which the
SPS128CR Power Card and the ring transformer are fastened. The mains
transformer is located on the SPS128CR Power Card. The module also has a 10-
pin cable for connection to the BPL128 Backplane.
SPS128 is a Switched Mode Power Supply (SMPS) operating at mains voltage.
Receiving 220 VAC over the mains, SPS128CR generates 5 VDC, -5 VDC, +12
VDC and -24 VDC for the system operation, for the accessories and for the ring
transformer. The ring transformer generates the 64 Vrms ring signal. Through the
10-pin power connector, the outputs of SPS128CR and ring transformer are
passed to the BPL128 Backplane, which carries them to the system modules. The
pin-out of the SPS128 – BPL128 connector on the backplane is as follows:
SPS128 – BPL128 Connector
Pin Signal Pin Signal
1 - 24 VDC 6 GND
2 GND 7 - 5 VDC
3 GND 8 GND
4 + 12 VDC 9 + 5 VDC
5 + 5 VDC 10 64 Vrms (Ring)
MS128 system can be backed up with a battery of 24 VDC in order to provide the
continuity of the operation in case of mains failure. Hence, SPS128CR has
necessary circuitries for battery backup. It is strongly recommended to use a dry
battery for proper operation of the system. Also a 24 V - 15 Ah battery is
recommended for a full capacity system with an average traffic of 35%.
There exists one F-type fuse of 8 A / 24 VDC for battery. The battery input is also
controlled by the battery ON/OFF switch, which enables the user to put the battery
out of service when necessary.
SPS128CR is also capable of charging the battery while the system power is on
and the system is running under low traffic. Besides, there exists a low voltage
battery cut-off circuitry, which turns itself off when the battery voltage goes below
17 VDC and does not start until the battery voltage is above 23 VDC. So,
preventing full discharge of the battery SPS128 makes the lifetime of the battery
longer.
The Power Status LEDs on the front panel of the SPS128 Power Supply Module
help to identify the power source in use on time. There are three LEDs. One is for
220 VAC and the others are for -24 VDC and +5 VDC. Normally when the system is
fed from the mains all three LEDs are on. The 220 VAC LED turns off when the
mains power is off. In this case - 24 VDC and + 5 VDC LEDs stay on, if battery
backup is available for the system.
The dimensions of the SPS128 are 9 cm x 26 cm x 23 cm and the weight is 2.2 kg
(including SPS128CR).
The dimensions of the SPS128CR are 5.5 cm x 18 cm x 20 cm and the weight is
0.9 kg.