8-2 Troubleshooting MN792

Alarm Messages When a trip occurs an alarm message is displayed at the keypad and information about the trip is stored in the
Alarm Status menu. The alarm message and the Last Alarm parameter are displayed. The Health Store and
Health Word parameters display information as hexadecimal values (0 – 9 and A, B, C, D, F shown in Table
8-1), or the sum of the hexadecimal values when more than one alarm is active. Therefore, the value can
represent one or more alarms. Table 8-1
Decimal number Display
10 A
11 B
12 C
13 D
14 E
15 F
The Last Alarm, Health Word and Health Store parameters use a four digit hexadecimal value to identify
individual trips. Each trip has a unique number.
Last Alarm (Tag [528]). This is 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 continuously monitors the control status. As alarms are added or removed, the
display immediately updates 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]). Stores 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).
Table 8-2

LAST ALARM, HEALTH WORD and HEALTH STORE

Trip Code
Trip First Digit Digit Digit Last Digit
No active alarms
0 Overspeed 1
1Missing pulse 2
2Field over I 4
3Heatsink trip * 8
4 Thermistor 1
5Over volts (VA) 2
6SPD Feedback 4
7Encoder failed 8
8Field failed 1
93 Phase failed * 2
10 Phase lock 4
11 5703 RCV Error 8
12 Stall trip 1
13 Over I trip 2
14 Other 4
15 ACCTS Failed * 8
For the last alarm parameter, other is replaced with the trip codes in Table 8-3.