Watlow Ez-Zone PM4 - Ordering Information for PID Controller Models; Controller Model Structure; Output and Communications Options

Watlow EZ-ZONE
®
PM PID Controller • 89 • Appendix
Indication Description Possible Causes Corrective Action
Process doesn’t control to set
point
Process is unstable or never
reaches set point
•Controllernottunedcorrectly
•Controlmodeisincorrectlyset
•Controlsetpointisincorrect
•Performautotuneormanually
tune system
•Setcontrolmodeappropriately
(Open vs Closed Loop)
•Setcontrolsetpointinappro-
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.
•Controlleroutputincorrectly
programmed
•Thermocouplereversewired
•Controlleroutputwiredincor-
rectly
•Shortinheater
•Powercontrollerconnectionto
controller defective
•Controlleroutputdefective
•Verifyoutputfunctioniscorrect
(heat or cool)
•Correctsensorwiring(redwire
negative)
•Verifyandcorrectwiring
•Replaceheater
•Replaceorrepairpowercon-
troller
•Replaceorrepaircontroller
[`100] Device Error
[rEtn]
Controller displays internal mal-
function message at power up.
•Controllerdefective •Replaceorrepaircontroller
Menus inaccessible
Unable to access [`SEt], [OP-
Er], [FCty] or [ProF] menus
or particular prompts in Home
Page
•Securitysettoincorrectlevel
•Digitalinputsettolockout
keypad
•Customparametersincorrect
•ChecklockoutsettinginFac-
tory Page
•Changestateofdigitalinput
•Changecustomparametersin
Factory Page
EZ-Key doesn’t work EZ-Key does not activate re-
quired function
•EZ-Keyfunctionincorrect
•EZ-Keyfunctioninstancenot
incorrect
•Keypadmalfunction
•VerifyEZ-KeyfunctioninSetup
Menu
•Checkthatthefunctionin-
stance is correct
•Replaceorrepaircontroller