User guide
Watlow EZ-ZONE
®
PM PID Controller • 110 • Appendix
Indication Description Possible Causes Corrective Action
Process doesn’t control to set
point
Process is unstable or never
reaches set point
•Controllernottunedcorrectly
•Controlmodeisincorrectlyset
•Controlsetpointisincorrect
•Performautotuneormanually
tune system
•Setcontrolmodeappropriately
(Open vs Closed Loop)
•Setcontrolsetpointinappro-
priate control mode and check
source of set point: remote, idle,
profile, closed loop, open loop
Temperature runway Process value continues to in-
crease or decrease past set
point.
•Controlleroutputincorrectly
programmed
•Thermocouplereversewired
•Controlleroutputwiredincor-
rectly
•Shortinheater
•Powercontrollerconnectionto
controller defective
•Controlleroutputdefective
•Verifyoutputfunctioniscorrect
(heat or cool)
•Correctsensorwiring(redwire
negative)
•Verifyandcorrectwiring
•Replaceheater
•Replaceorrepairpowercon-
troller
•Replaceorrepaircontroller
[`100] Device Error
[rEtn]
Controller displays internal mal-
function message at power up.
•Controllerdefective •Replaceorrepaircontroller
Menus inaccessible
Unable to access [`SEt], [OP-
Er], [FCty] or [ProF] menus
or particular prompts in Home
Page
•Securitysettoincorrectlevel
•Digitalinputsettolockout
keypad
•Customparametersincorrect
•ChecklockoutsettinginFac-
tory Page
•Changestateofdigitalinput
•Changecustomparametersin
Factory Page
EZ-Key doesn’t work EZ-Key does not activate re-
quired function
•EZ-Keyfunctionincorrect
•EZ-Keyfunctioninstancenot
incorrect
•Keypadmalfunction
•VerifyEZ-KeyfunctioninSetup
Menu
•Checkthatthefunctionin-
stance is correct
•Replaceorrepaircontroller
Troubleshooting Alarms, Errors and Control Issues (cont.)