Emerson 5081-P Manuel D’Utilisation
iii
MODEL 5081-P pH/ORP
TABLE OF CONTENTS
TABLE OF CONTENTS CONT’D
12.0
TROUBLESHOOTING ...........................................................................................
109
12.1
Warning and Fault Messages ..................................................................................
109
12.2
Calibration Errors .....................................................................................................
110
12.3
Troubleshooting - General .......................................................................................
110
12.4
Troubleshooting When a diagnostic Message is Showing ......................................
110
12.5
Troubleshooting When No diagnostic Message is Showing....................................
122
12.6
displaying diagnostic Variables...............................................................................
127
12.7
Testing the Transmitter by Simulating pH ................................................................
127
12.8
Factory Assistance and Repairs ..............................................................................
130
13.0
pH MEASUREMENTS.............................................................................................
131
13.1
General ....................................................................................................................
131
13.2
Measuring Electrode ................................................................................................
132
13.3
Reference Electrode ................................................................................................
132
13.4
Liquid Junction Potential ..........................................................................................
133
13.5
Converting Voltage to pH .........................................................................................
133
13.6
Glass Electrode Slope .............................................................................................
134
13.7
Buffers and Calibration ............................................................................................
134
13.8
Isopotential pH .........................................................................................................
135
13.9
Junction Potential Mismatch ....................................................................................
135
13.10 Sensor diagnostics ..................................................................................................
136
13.11
Shields, Insulation, and Preamplifiers......................................................................
136
14.0
ORP MEASUREMENTS..........................................................................................
137
14.1
General ....................................................................................................................
137
14.2
Measuring Electrode ................................................................................................
138
14.3
Reference Electrode ................................................................................................
138
14.4
Liquid Junction Potential ..........................................................................................
138
14.5
Relating Cell Voltage to ORP...................................................................................
139
14.6
ORP, Concentration, and pH....................................................................................
139
14.7
Interpreting ORP Measurements .............................................................................
140
14.8
Calibration................................................................................................................
142
15.0
THEORy — REMOTE COMMUNICATIONS...........................................................
143
15.1
Overview of HART Communications........................................................................
143
15.2
HART Interface devices...........................................................................................
143
15.3
Asset Management Solutions ..................................................................................
144
16.0
RETURN OF MATERIAL.........................................................................................
145