Hach Sigma 950, Instrument Manual, Page: 5 / 146

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8.4 Alarm Relays.............................................................................................................................. 68
8.4.1 Alarm Relay Connections ................................................................................................. 68
8.4.2 Alarm Relays Programming .............................................................................................. 69
8.4.2.1 Trouble Alarms......................................................................................................... 69
8.4.2.2 Set Point Alarms ...................................................................................................... 70
Section 9 Maintenance
.................................................................................................................... 71
9.1 Routine Maintenance ................................................................................................................. 71
9.1.1 Calibration......................................................................................................................... 71
9.1.2 Cleaning the Case ............................................................................................................ 71
9.1.3 Maintaining Desiccant Cartridges and Desiccant ............................................................. 72
9.1.3.1 Replacing the Desiccant .......................................................................................... 72
9.1.3.2 Rejuvenating the Desiccant ..................................................................................... 72
9.1.3.3 Maintaining the Hydrophobic Membrane ................................................................. 72
9.2 Upgrades, Repairs, General Maintenance................................................................................. 72
9.2.1 Internal Maintenance Items............................................................................................... 73
9.2.2 Removing the Front Panel ................................................................................................ 73
9.2.3 Re-Installing the Front Panel ............................................................................................ 74
9.3 Circuit Board Identification ......................................................................................................... 75
9.4 Fuse and Connector Locations .................................................................................................. 75
9.4.1 Fuse Removal and Inspection .......................................................................................... 77
9.4.2 Working with Wiring Connectors....................................................................................... 78
9.5 Replacing the Internal Desiccant Module .................................................................................. 78
9.6 Replacing the Internal Case-Humidity Indicator Disc................................................................. 78
9.7 Memory Batteries....................................................................................................................... 79
Appendix A Program Flow Charts
................................................................................................ 81
Appendix B Programming Features
............................................................................................. 87
Appendix C Primary Devices & Head Measurement Locations
........................................... 101
Appendix D Programming Worksheet
....................................................................................... 105
Appendix E SCADA-Modbus
®
System Guidelines
................................................................. 109
Appendix F Batteries and Chargers
........................................................................................... 125
Appendix G Troubleshooting
................................................................................................. 129
Appendix H Manning Roughness Coefficients
........................................................................ 135
Appendix I Engineering Drawings
.............................................................................................. 137