© Edwards Limited 2015. All rights reserved.
Page 59
Edwards and the Edwards logo are trademarks of Edwards Limited.
Appendix A2
A540-55-880 Issue D
A2.3
Inverter warnings and alarms
The inverters used to drive the dry pump and booster can also generate warnings and alarms if problems are
encountered. Inverter warning and alarm codes are displayed by the PDT if fitted.
The alarm and warning codes are each reported as a 16-bit word encoded as 4 hexadecimal numbers. The codes are
displayed as follows:
1234 5678
Where:
The first 4 digits signify an Alarm code and,
The second 4 digits signify a Warning code,
Digits 1 – 8 are reported as hexadecimal digits from 0 to F.
To determine the cause of a warning or alarm, first decode each hexadecimal number. 0 indicates that there is no
alert for that bit. Normally, only codes of 1, 2, 4 or 8 will be displayed for each bit but, if two or more events occur
in the same bit, then these will be added together.
For example:
5 = 1 + 4 so if code 5 is displayed it means that alerts 1 AND 4 are active
B = 1 + 2 + 8 so if code B is displayed it means that alerts 1, 2 AND 8 are active.
To decode inverter warning and alarm codes, refer to
to convert the hexadecimal digits into alert
combinations and then refer to
and
).
Table A15 - Hexadecimal to digital conversion
BIT SET COMBINATIONS
HEXADECIMAL
DECIMAL
Combination
F
15
8+4+2+1
E
14
8+4+2
D
13
8+4+1
C
12
8+4
B
11
8+2+1
A
10
8+2
9
9
8+1
8
8
8
7
7
4+2+1
6
6
4+2
5
5
4+1
4
4
4
3
3
2 + 1
2
2
2
1
1
1
