Allen bradley "ENERGY STORAGE OK" light out

[ABnewb]

I have a PLC that has the "Energy storage OK" light out (pictured below). Is this a bug in the software, or does the energy storage module need to be replaced?

I've read through the manuals for the controller and I can't find a procedure to replace the ESM.

How long can a PLC typically be de-energized before draining the ESM?

 

[ABnewb]

Also, I had failed to mention that the controller did not indicate any faults, major or minor.

The original failure was that the controller lost the program. I believe it may have been de-energized, but I don't know if it was for a split second or for hours.

When I connected to it, everything was entirely wiped.

 

[AustralIan]

It uses the same LEDs as your controller.

the 1769-LxxER do not have an LED for the Energy storage module, so the LED is always off. Energy storage OK indicates that your energy storage is OK.

"The status data area contains icons to represent the RUN, I/O, BAT (or Energy Storage), and OK LEDs on your controller hardware. These LEDs use the same colors and solid/blinking states used by the real LEDs on your controller."
--Help file.

 

[garlantm]

Hello,

Going to sound like a stupid question. Are you sure your controller has an ESM? Not all PLC's have it and Im pretty sure that if you do have this it causes a Fault not just a grey light (instead of green).

 

[jraef]

I would think that if you have had an issue with the PLC losing memory AND you don't have the ESM light on, it would indicate that your ESM battery is dead. That's what the light is for... to warn you that the next time power is lost, you will lose the RAM memory. The ones that don't have the battery are those that don't need it because they store the user program in EEPROM or an SD card, so the fact that you lost your program would indicate that yours does not have that type of memory and needs the battery.

 

[ABnewb]

I was looking at the specs from Rockwell and the L36ERM controller states the following feature:

Built-in energy storage eliminates
the need for lithium batteries.

But I can't find any procedure to replace it.

Also, it does have an SD card. However, when I navigated to the "nonvolatile memory" under "controller properties", it would not let me download to it. And it did not contain an image.

 

[ABnewb]

I've read that there may have been a manufacturing problem with the ESM's, but I can't locate the white paper.

 

[AustralIan]

Your energy storage is fine. It says "Energy Storage OK". The text changes to show the status, for example, here is the wrong I/O used on a CompactLogix.

There were no faults?

You have to go to program mode to be able to Load/Store.. from controller properties. You might have 'do firmware update' or 'load image on powerup' ticked in this dialog.

 

[RET]

Yea, that box is greyed out when all is ok, but will turn red if there's a fault with the ESM. That threw me off a while back and had to figure that out.