Eaton POWERWARE Plus 18, Руководство пользователя

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Board Descriptions
Plus 18
provide a positive DC source Volts). This positive DC source filtered by
capacitors C4 and and is then regulated down to Volts by regulator, U3.
Capacitors C6
and provide a bypass function and help to improve the stability and
response of U3. D3 and D4 along with filter capacitors
a negative DC source (-12 Volts). The Volts is used by IC
IC and the PC112 US, The plus and 12
Volt are used by the RS-232 driver 1488.
isolated chassis connection
the common
Relay
signals sent from the front panel board to this board via These signals
are fed to the input of a in order provide an open-collector drive for the
relays.
the output of the 7407 leaves me relay ~&-energized contact is to
COMMON). When a is applied to the receiver’s inputs, relay is energized.
are clamps for the relay coils to prevent an overvoltage from occurring on
the outputs of the 7407 when the relays am
The relays each have
contacts
maintain compatibility, pin 8 of the 26-pin
17 of the DB-25)
can be programmed to be or N.C. via
Therelays
provide isolation and meat VDE IEC
%-Pin
The
the primary interface to the UPS alarms and
serial data for the is pinned out to provide a RS-232 with
hardware handshaking capability DTR, DSR) when via ribbon
and are referenced to isolated ground. Table 1 detailed pin-out for
ELECTRONICS