Watlow Electric EZ-ZONE PM manual 70

Indication	Description	Possible Cause(s)	Corrective Action
Process doesn’t con-	Process is unstable or never	• Controller not tuned correctly	• Perform autotune or manually tune
trol to set point	reaches set point		system
		• Control mode is incorrectly set	• Set control mode appropriately (Open
			vs Closed Loop)
		• Control set point is incorrect	• Set control set point in appropriate
			control mode and check source of set
			point: remote, idle, profile, closed loop,
			open loop
Temperature runway	Process value continues to	• Controller output incorrectly pro-	• Verify output function is correct (heat
	increase or decrease past set	grammed	or cool)
	point.
		• Thermocouple reverse wired	• Correct sensor wiring (red wire nega-
			tive)
		• Controller output wired incorrectly	• Verify and correct wiring
		• Short in heater	• Replace heater
		• Power controller connection to con-	• Replace or repair power controller
		troller defective
		• Controller output defective	• Replace or repair controller
[`100] Device Error	Controller displays internal	• Controller defective	• Replace or repair controller
[rEtn]	malfunction message at
	power up.
[`h;Er] Heater Error	Heater Error	• Current through load is above current	• Check that the load current is proper.
		trip set point	Correct cause of overcurrent and/or en-
			sure current trip set point is correct.
		• Current through load is below current	• Check that the load current is proper.
		trip set point	Correct cause of undercurrent and/or
			ensure current trip set point is correct.
[`C;Er]	Load current incorrect.	• Shorted solid-state or mechanical	• Replace relay
Current Error		relay
		• Open solid-state or mechanical relay	• Replace relay
		• Current transformer load wire associ-	• Route load wire through current
		ated to wrong output	transformer from correct output, and
			go to the [`C;Si] Source Output In-
			stance parameter (Setup Page, Current
			Menu) to select the output that is driv-
			ing the load.
		• Defective current transformer or con-	• Replace or repair sensor or controller
		troller
		• Noisy electrical lines	• Route wires appropriately, check for
			loose connections, add line filters
Menus inaccessible	Unable to access [`SEt],	• Security set to incorrect level	• Check lockout setting in Factory Page
	[OPEr], [FCty] or [ProF]
	menus or particular prompts
	in Home Page
		• Digital input set to lockout keypad	• Change state of digital input
		• Custom parameters incorrect	• Change custom parameters in Factory
			Page
EZ-Key doesn’t work	EZ-Key does not activate re-	• EZ-Key function incorrect	• Verify EZ-Key function in Setup Menu
	quired function
		• EZ-Key function instance not incor-	• Check that the function instance is
		rect	correct
		• Keypad malfunction	• Replace or repair controller

Watlow EZ-ZONE®PM Integrated Controller • 68 • Appendix