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Gas High and High-High Alarms
Part 17997
Rev. 6, March 2011
10-13
Note the following points:
• If the Hydran 201T
i
undergoes a power failure that lasts less than 1/6 of the trend period,
the corresponding trend reading remains constant until the H201T
i
is powered up again.
• If the power failure lasts more than 1/6 of the trend period, the corresponding trend
reading is reset to zero.
• If the user changes the hourly or daily trend period, the corresponding trend reading is
reset to 0.0 ppm/period.
10.4.4 High and High-High Alarms Triggering
If the High alarm relay is set to the
Normal
or
Latch
mode, the High alarm is triggered (the
High alarm relay is energized) when one of the alarm conditions
exceeds
the corresponding
High alarm set point during a period of time exceeding its alarm delay.
The same way, if the High-High alarm relay is set to the
Normal
or
Latch
mode, the High-
High alarm is triggered (the High-High alarm relay is energized) when one of the alarm
conditions
exceeds
the corresponding High-High alarm set-point during a period of time
exceeding its alarm delay.
Each alarm (High and High-High) can be triggered by one or several of the following
conditions (for details, see Section 10.1.1 on page 10-2):
• Gas level (
GasLevel
submenu)
• Hourly trend (
HourlyTrend
submenu)
• Daily trend (
DailyTrend
submenu)
Each alarm condition has an adjustable alarm delay that is common to all levels (High,
High-High, Low and Low-Low) of this condition.
10.4.5 High and High-High Alarms Cancellation
Note: To be cancelled, an alarm condition must disappear during a period of time
exceeding the corresponding alarm delay.
To cancel a High or High-High alarm, proceed as follows:
1.
Find and solve the problem. Generally, the Hydran 201T
i
’s reading must be verified
by sampling the transformer’s oil and performing a dissolved gas analysis (DGA)
Summary of Contents for Hydran 201i
Page 1: ...GE Energy Services Digital Energy Hydran Instruction Manual 201i System ...
Page 6: ...Instruction Manual vi Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 8: ...Instruction Manual viii Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 22: ...Instruction Manual xxii Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 36: ...Chapter 1 Introduction 1 10 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 114: ...Chapter 5 Before Installation 5 16 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 143: ...Installation Part 17997 Rev 6 March 2011 6 29 Figure 6 9 Installing the CPU Module ...
Page 236: ...Chapter 12 Troubleshooting 12 20 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 244: ...Chapter 13 Maintenance 13 8 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 254: ...Appendix B Mechanical Drawings B 2 Rev 6 March 2011 Part 17997 Figure B 3 1 5 In Adaptor ...
Page 255: ...Hydran 201Ti Intelligent Transmitter Part 17997 Rev 6 March 2011 B 3 Figure B 4 1 In Adaptor ...
Page 284: ...Appendix G Unit Conversions G 2 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 298: ...Appendix I Glossary I 12 Rev 6 March 2011 Part 17997 PAGE LEFT INTENTIONALLY BLANK ...
Page 299: ......