APC DC Power Plant MX28B-1200 - Manual (Page 38)

MX28B-1200 PRODUCT MANUAL Revision B
32 MX28B-1200/2400
permits modification of some parameters; no security is required for viewing status items. The
security level password is entered through the “PIN” screen. If no front panel keys are pressed
for 60 minutes, the active password reverts to “0000” and “█APC█” begins to move about the
display. Pressing any key returns the display to normal; the password must be re-entered if
system parameters require changes. The default passwords for level 1 and level 2 are “1111”
and “2222”, respectively. There are no alternate passwords or “backdoors” for accessing the
system. A forgotten password may require a new master controller board, at customer expense.
System control parameters are stored in non-volatile memory and will not be erased when power
is removed for the master control unit. However, if a new program EPROM is installed or a
different device model selected, the system control parameters will be re-initialized to the
factory default settings.
Eleven LEDs are provided on the front panel of the control unit to indicate system status. Three
LEDs grouped together vertically provide overall system status; they are “MAJOR”, “MINOR”,
and “NORMAL”, indicating the presence of a major alarm, a minor alarm, or normal operation.
The other eight LEDs correspond to the active state of each of the alarm output relays and are
labeled “ALM1”∙∙∙“ALM6”, “MIN”, and “MAJ”.
6.2 External Alarm Inputs
The four external alarm inputs (also referred to as “Input Relay Alarms”) can be assigned a
priority and routed or “mapped” to alarm output relays. Available assignments are “Ignore”,
“Major”, “Minor”, and “Relay 1” ∙∙∙ “Relay 6”. Screens for making the assignments are
located at [SYSTEM/IN-RLY/RLY-MAP]. This special menu notation is explained with an
example in section 6.4
A user defined name or “alias” may also be assigned to each of these input alarms. Screens for
making these assignments are located at [SYSTEM/IN-RLY/ALIAS]. For information on
wiring connections to these inputs refer to Section 5.7.1.
6.3 Alarm Output Relays
There are eight alarm output relays designated Relay 1 through Relay 6, Minor, and Major,
respectively. Various system parameters may be programmed to activate any of these alarm
relays when set thresholds are exceeded or specific conditions occur. The first six relays can
also be assigned a priority and routed or “mapped” to other output alarm relays. Available
assignments are “Ignore”, “Major”, “Minor”, and “Relay 1” ∙∙∙ “Relay 6”. Screens for making
these assignments are located at [SYSTEM/OUT-RLY/RLY-MAP]. This feature makes it
possible for a single alarm condition to activate multiple alarm output relays including the Minor
or Major alarm relay. A user defined name or “alias” may also be assigned to each of the eight
output relay alarms. Screens for making these assignments are located at [SYSTEM/OUT-
RLY/ALIAS]
. For information on making wiring connections to the alarm output relays refer
to Section 5.7.2.
6.4 Parameter Locations, Descriptions, and Default Values
The location, description, and factory programmed default value for each of the MX28B system
parameters is found in Table 6-1. The table also shows all of the status and information screens
with typical displays. The location of a parameter screen is shown in brackets, for example:
[SYSTEM/IN-RLY/RLY-MAP]
. To find the parameters that can be accessed in this category,
starting from the main menu screen, do the following: