Temperature controllers
Watlow EZ-ZONE Temperature Controller fault codes
What all 9 Watlow EZ-ZONE Temperature Controller fault codes mean, in plain words, with a risk grade for each. These come from the manufacturer's own manual. The fix for each one is in WERCS Diagnose.
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| Code | What it means | Risk |
|---|---|---|
| ---- | ---- (four dashes in upper display) A sensor failure has occurred, causing dashes to appear instead of the process value on the upper display. | YELLOW |
| OpEn | OpEn (Input Error i.Er value = Open) The analog input is open, triggering an active error input message on the controller. | YELLOW |
| shrt | shrt (Input Error i.Er value = Shorted) The analog input is shorted, triggering an active error input message on the controller. | YELLOW |
| AL.E1 | AL.E1 (Alarm Error 1) The alarm is in an error state and cannot be evaluated due to a lost or faulty sensor input. | YELLOW |
| AL.L1 | AL.L1 (Alarm Low 1, toggling with Attn) The process value has dropped to or below the low alarm setpoint, triggering an active attention message. | GREEN |
| AL.h1 | AL.h1 (Alarm High 1, toggling with Attn) The process value has reached or exceeded the high alarm setpoint, triggering an active attention message. | GREEN |
| Er.i1 | Er.i1 (Error Input 1, toggling with Attn message) An input error is active on the attention parameter, meaning a specific sensor or calibration fault is present. | YELLOW |
| vaL.L | vaL.L (value too low to display, less than -1999) The process value is less than negative 1999 and is too low to be shown on the four digit display. | GREEN |
| vaL.h | vaL.h (value too high to display, greater than 9999) The process value is greater than 9999 and is too high to be shown on the four digit display. | GREEN |
Every code comes from the manufacturer's own manual. Subscribers see which manual and page.