Troubleshooting Procedures - Honeywell UDC 3500 Application Note

U U D D C C
U D
C
Upper Lower
Display Display
Display does not change when a key is pressed
Controller fails to go into "Slave" operation during communications
Bad PV Reading Bad InX
Reading
Other symptoms
If a set of symptoms or prompts other than the one you started with appears while
troubleshooting, re-evaluate the symptoms. This may lead to a different troubleshooting
procedure.
If the symptom still persists, refer to the installation section in this manual to ensure
proper installation and proper use of the controller in your system.

Troubleshooting Procedures

Introduction
The troubleshooting procedures are listed as they appear in Table-1. Each procedure
describes what to do if you have that particular failure and how to do it or where to find
the data needed to accomplish the task.
TROUBLESHOOTING MAY REQUIRE ACCESS TO HAZARDOUS LIVE
CIRCUITS AND SHOULD ONLY BE PERFORMED BY QUALIFIED SERVICE
PERSONNEL. MORE THAN ONE SWITCH MAY BE REQUIRED TO DE-
Equipment needed
You will need the following equipment in order to troubleshoot the symptoms listed:
• Multimeter – Capable of measuring millivolts, volts, milliamps and resistance.
• Calibration sources – T/C, mV, Volt, etc.
3 3 5 5 0 0 0 0 A A
3 5 0 0 A
Indicators
OK
WARNING—SHOCK HAZARD
ENERGIZE UNIT BEFORE SERVICING.
Page 2 of 16
p p p p l l i i c c a a t t i i o o
p p l i c a t i o
Controller
Output
Communications
OK
Revision 1
n n N N o o t t e e
n N o t e
Probable Trouble-
Cause shooting
Procedure
Keyboard
Malfunction
RS-485: 0
Failure
Ethernet: 0
Analog Input
Failure
0
0