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Trips and Fault Finding
7-5
590+ Series DC Digital Converter
Alarm Messages
When a trip occurs an alarm message is displayed on the MMI, and information about the trip is
stored in the ALARM STATUS menu.
The alarm message and the LAST ALARM parameter are displayed in the selected language of
the MMI.
The HEALTH STORE and HEALTH WORD parameters display information as hexadecimal
values, or the sum of the hexadecimal values when more than one alarm is active. Thus the
unique value can represent one or more alarms.
Note:
Hexadecimal refers to the common practice of counting to the base of 16 in computing
rather than the base of 10. The sixteen `numbers’ used being 0 to 9, A to F. Thus an 8
bit byte is represented by two characters in the range 00 to FF, while a 16 bit word is
represented by four characters in the range 0000 to FFFF.
LAST ALARM
(Tag 528). This display shows the last alarm message to have been displayed. To reset the
parameter simply press the
▼
(DOWN) key to clear the alarm. Alternatively, you can switch the
auxiliary supply off and on, causing NO ACTIVE ALARMS to be
displayed.
HEALTH WORD
(Tag 115).This parameter is used to continuously monitor the status of
the Converter. As alarms are added or removed, the display will immediately update to show the
hexadecimal sum of these alarms.
The value reverts to 0x0000 when the Start (C3) input is raised (+24V), and when no trip
condition is present.
HEALTH STORE
(Tag 116).This displays the hexadecimal value of the first (or only) alarm to occur causing the
trip condition.
The display reverts to 0x0000 when the Start (C3) input is raised (+24V).
MMI Menu Map
1
ALARM STATUS
LAST ALARM
HEALTH WORD
HEALTH STORE