Honeywell UDC3500 Product Manual page 8

7.2 Troubleshooting Aids..................................................................................................................288
7.3 Power-up Tests............................................................................................................................290
7.4 Status Tests .................................................................................................................................290
7.5 Background Tests and Diagnostic Messages ..............................................................................291
Controller Failure Symptoms ...............................................................................................................295
7.6 Troubleshooting Procedures .......................................................................................................296
7.6.1 Procedure #1 - Power ......................................................................................................297
7.6.2 Procedure #2 - Current Outputs.......................................................................................297
7.6.3 Procedure #3 - Position Proportional ..............................................................................299
7.6.4 Procedure #4 - Time Proportional ...................................................................................302
7.6.5 Procedure #5 - Current/Time or Time Current/Proportional...........................................303
7.6.6 Procedure #6 - Alarm Relays ..........................................................................................304
7.6.7 Procedure #7 - Keyboard.................................................................................................306
7.6.8 Procedure #8 - Analog Input ...........................................................................................307
7.6.9 Procedure #9 - RS-485 ....................................................................................................308
7.6.10 Procedure #10 - Ethernet .............................................................................................311
7.6.11 Procedure #11 - Email .................................................................................................312
7.7 Restoring Factory Configuration ................................................................................................313
7.8 Software Upgrades......................................................................................................................314
8 PARTS LIST ...................................................................................................... 316
8.1 Exploded View............................................................................................................................316
8.2 Removing the chassis..................................................................................................................318
9 MODBUS RTU FUNCTION CODES.................................................................. 319
9.1 Overview.....................................................................................................................................319
9.2 General Information....................................................................................................................319
9.3 Function Code 20 (14h) - Read Configuration Reference Data..................................................321
9.3.1 Read Configuration Examples .........................................................................................323
9.4 Function Code 21 (15h) - Write Configuration Reference Data.................................................325
9.4.1 Write Configuration Examples ........................................................................................327
10 MODBUS READ, WRITE AND OVERRIDE PARAMETERS PLUS EXCEPTION
CODES........................................................................................................................ 328
10.1 Overview .................................................................................................................................328
10.2 Reading Control Data..............................................................................................................329
10.3 Read Software Options Status .................................................................................................331
10.4 Miscellaneous Read Onlys ......................................................................................................332
10.4.1 Register Addresses for Read Onlys ..............................................................................332
10.4.2 SetPoint Program Read Only Information....................................................................332
10.5 Setpoints ..................................................................................................................................333
10.6 Using a Computer Setpoint (Overriding Controller Setpoint) ................................................335
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