Eaton POWERWARE Plus 18, Руководство пользователя

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Board Descriptions
Plus 18
The handshake line, RTS, is an input to the microprocessor. The unused handshake
inputs and RI) are brought onto the board and tied to a
l
voltage level asserts ready state of operation. DSR is unused
microprocessor output. The presence of the handshake lines and
is for implementation of future communications options.
The Relay RLY 1 4. are used to or de-energize the coil of the
are driven by the microprocessor and allow of Relay
interface comply with various interface NOVELL. etc.,
5.8 EXPANDER BOARD
The Board serves as the customer interface to the UPS. It provides an
interface to: 1) the relays, 2) the RS-232 communication port, and 3)
the Interface Board. A three-way splitter cable will allow operation
ground or are isolated logic common (as is the case with the relay contacts).
Isolated logic common can connected to logic (chassis ground) by
a plug at jumper ‘W 1’. In the standard the plug is
installed on position l-2
which mates with the front header, J2. which
DB-25 for customer This is with more detail in Section 7.
level
RS-232
signals the front panel are converted to isolated
RS-232 levels at the 26
Isoliated Power Supply
Power for the isolated is derived from the volt regulator, The diode,
1. provides reverse bias protection for U12. A 4 oscillator, Y 1. powered by
volts supplied by the front panel, drives a square wave where it is divided
along with R13. provide the drive to
current limiting is provided by resistors
and R3. Cl, and as bypass caps and help radiated
noise.
The of isolated to the circuitry. The
is center-tapped the center-tap
a plug installed at to chassis (earth) ground
provide a positive DC source Volta). This positive DC source is filtered by
C6 and provide a bypass and help to improve the stability and
response of U3. D3 D4 along with filter provide
ELECTRONICS CONFIDENTIAL
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