Mitel SX-200 Documentation page 478

l
-5 volts
-10 volts
0 volts (chassis ground)
-48 volts (-48 Vl)
-48 volts (-48 V2).
8.44 These levels are regulated within 5 % except for the -48 Vdc
which may vary by 10 % . An out-of-tolerance (OOT) circuit
monitors all levels continuously and should an out-of-tolerance de-
viation occur, the output of this circuit is used to activate the power
fail transfer circuitry.
8.45 The ringing generator uses one of the -48 Vdc outputs from the
main converter to produce a 90 volt, 20 Hz supply which is
used within the system (ringing, message waiting) and which is also
accessible for night bells, etc.
Reserve Power Supplies
8.46 The PBXs are designed to operate from a 48 Vdc source. This
source is provided from the power supply, contained within the
SX-100 or SX-200 equipment and which operates from a 115 Vat
(optionally 230 Vat) commercial source. A reserve power supply can
. .
be provided to supply 48 Vdc in the case of commercial power failure.
The reserve power supply consists of two major assemblies as follows,
which are differently packaged to meet the SX-100 (see paragraph
8.47) and SX-200 (see paragraph 8.48) requirements: a battery pack of
eight batteries .providing
compensated battery charging unit operating from the commercial
main source and which maintains the proper battery voltage.
SX-100 Reserve Power Supply
8.47 The SX-100 reserve power supply consists of a single enclosed
assembly. This assembly forms the base unit upon which the
SX-100 cabinet may be mounted, and is supplied with a cable harness
to interconnect the 48 Vdc supply between the two units. In the case
of the wall-mount version of the SX-100 system, the reserve power
supply can be installed adjacent to the SX-100 system, but will require
a locally fabricated cable harness to interconnect the PBX and the
reserve power supply. The SX-100 reserve power supply is 635 mm
(25 in.) wide, 470 mm (18.5 in.) deep, 203 mm (8 in.) high and weighs
49.4 kg (108 lb).
SX-200 Reserve
8.48 The SX-200 reserve power supply is intended for installation
within the lower portion of the cabinet. The battery pack is
contained within a shelf unit which is mounted immediately below
Shelf Unit 1, and the charging unit is mounted from the rear of the
cabinet. The battery supply is housed in a completely enclosed shelf
measuring 178 mm (7 in.) high, 483 mm (19 in.) wide, 381. mm (15 in.)
SECTION
48.3 Vdc at 2O"C, and a temperature-
Power Supply
91 OS/91 10-096-l 80-NA
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