System Troubleshooting With Checkback - Ametek UPLC-II System Manual

6.5 System Troubleshooting with
Checkback
You can identify and solve many checkback net-
work problems by examining the major and minor
alarms. If low power checkback tests are enabled in
addition to high power tests, the major and minor
alarms work like this:
• If a unit fails only the low power test, it sets
the minor alarm
• If a unit fails the high power test, it sets the
major alarm
• If a unit fails the high power test and can not
receive its own messages, it sets both major
and minor alarms
Armed with this information, you can usually iden-
tify a failed unit or line problem. The System
Master Module
Major Minor
clear clear
clear clear
clear clear
clear clear
clear set
clear set
clear set
clear set
set clear
set clear
set clear
set clear
set set
set set
set set
set set
January 2016
Troubleshooting table lists all combinations for a
two-unit system and the probable situation.
To get the complete picture, you must wait long
enough for all remotes to initiate their own check-
back tests. For example, if the master has a major
alarm, but the remote has no alarms, you can not
determine if it failed to receive the command due to
a bad line or because its receiver failed. By waiting
for the remote to initiate a checkback, you can tell
if it is the line (major alarm) or the unit (both
alarms). Some customers use a N.O. Major alarm
and a N.O. Minor alarm output in series to give a
"local" alarm so they can know which end of the
line has a problem. Both Major & Minor alarms
occurring on one UPLC-II™ means that this partic-
ular UPLC-II™ in the system is bad.
Table 6–3. System Troubleshooting
ALARMS
Remote Module
Major
clear
clear
set
set
clear
clear
set
set
clear
clear
set
set
clear
clear
set
set
Chapter 6. Testing Facilities
Probable Situation
Minor
clear All OK
set Weak/noisy line
clear Master or line failed
set Remote failed
clear Weak/noisy line
set Weak/noisy line
clear Weak/noisy line or master failed
set Remote failed
clear Remote or line failed
set Remote or line failed
clear Line failed
set Remote failed
clear Master failed
set Master failed
clear Master failed
set Master and remote failed
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