Watlow ez-zone pm - Page 122

Watlow EZ-ZONE
®
PM Integrated Controller • 119 • Chapter 11 Appendix
Indication Description Possible Cause(s) Corrective Action
[Li;h1] Limit High
Sensor input above high limit
set point
•Temperatureisgreaterthanlimitset
point
•Limitoutputslatchandrequirereset
•Incorrectalarmsetpoint
•Checkcauseofovertemperature
•Clearlimit
•Establishcorrectlimitsetpoint
[LP;o1]
LP;o2]
Loop Open Error
Open Loop Detect is active
and the process value did
not deviate by a user-select-
ed value in a user specified
period with PID power at
100%.
•SettingofOpenLoopDetectTime
incorrect
•SettingofOpenLoopDetectDevia-
tion incorrect
•Thermalloopisopen
•OpenLoopDetectfunctionnotre-
quired but activated
•SetcorrectOpenLoopDetectTimefor
application
•SetcorrectOpenLoopDeviationvalue
for application
•Determinecauseofopenthermalloop:
misplaced sensors, load failure, loss of
power to load, etc.
•DeactivateOpenLoopDetectfeature
[LP;r1]
[LP;r2]
Loop Reversed Error
Open Loop Detect is active
and the process value is
headed in the wrong direc-
tion when the output is
activated based on devia-
tion value and user-selected
value.
•SettingofOpenLoopDetectTime
incorrect
•SettingofOpenLoopDetectDevia-
tion incorrect
•Outputprogrammedforincorrect
function
•Thermocouplesensorwiredinreverse
polarity
•SetcorrectOpenLoopDetectTimefor
application
•SetcorrectOpenLoopDeviationvalue
for application
•Setoutputfunctioncorrectly
•Wirethermocouplecorrectly,(redwire
is negative)
[`rP1] Ramping 1
[`rP2] Ramping 2
Controller is ramping to new
set point
•Rampingfeatureisactivated •Disablerampingfeatureifnotre-
quired
[tUN1] Autotuning 1
[tUN2] Autotuning 2
Controller is autotuning the
control loop
•Userstartedtheautotunefunction
•Digitalinputissettostartautotune
•Waituntilautotunecompletesordis-
able autotune feature
•Setdigitalinputtofunctionother
than autotune, if desired
No heat/cool action Output does not activate load •Outputfunctionisincorrectlyset
•Controlmodeisincorrectlyset
•Outputisincorrectlywired
•Load,powerorfuseisopen
•Controlsetpointisincorrect
•Incorrectcontrollermodelforapplica-
tion
•Setoutputfunctioncorrectly
•Setcontrolmodeappropriately(Open
vs Closed Loop)
•Correctoutputwiring
•Correctfaultinsystem
•Setcontrolsetpointinappropriate
control mode and check source of set
point: remote, idle, profile, closed loop,
open loop
•Obtaincorrectcontrollermodelforap-
plication
No Display No display indication or LED
illumination
•Powertocontrollerisoff
•Fuseopen
•Breakertripped
•Safetyinterlockswitchopen
•Separatesystemlimitcontrolacti-
vated
•Wiringerror
•Incorrectvoltagetocontroller
•Turnonpower
•Replacefuse
•Resetbreaker
•Closeinterlockswitch
•Resetlimit
•Correctwiringissue
•Applycorrectvoltage,checkpart
number
No Serial Communi-
cation
Cannot establish serial com-
munications with the con-
troller
•Addressparameterincorrect
•Incorrectprotocolselected
•Baudrateincorrect
•Parityincorrect
•Wiringerror
•EIA-485converterissue
•IncorrectcomputerorPLCcommuni-
cations port
•Incorrectsoftwaresetup
•Wiresroutedwithpowercables
•Terminationresistormayberequired
•Setuniqueaddressesonnetwork
•Matchprotocolbetweendevices
•Matchbaudratebetweendevices
•Matchparitybetweendevices
•Correctwiringissue
•Checksettingsorreplaceconverter
•Setcorrectcommunicationport
•Correctsoftwaresetuptomatchcon-
troller
•Routecommunicationswiresaway
from power wires
•Place120ΩresistoracrossEIA-485
on last controller