How long a SLC program can last w/o batt/EEPROM/power up?

[ckchew666]

Hi,

Has anyone check how long a SLC program (5/04) can last in the CPU without battery & EPROM?

The PLC is not power on.

One of our customer tried and it last for 4 days....and still counting. We go online and upload the program every 2 days and it's still working fine!

Is the capacitor is the backup source for the SLC5/04?

Any feedback...?

 

[Terry Woods]

Zero-time.

 

[Lancie1]

ckchew666,

This is what Allen-Bradley says about the capacitor:

The SLC 5/03, 5/04 and 5/05 processors have a capacitor that provides at least 30 minutes of battery back-up while the battery is disconnected. Data in RAM is not lost if the battery is replaced within 30 minutes.

I have found that the capacitor will last a lot longer than 30 minutes. I have had a PLC 5/03 out for about 3 hours. This was the time to move a machine from one plant to another, but then we discovered that the PLC battery was missing, but the program was still in place. Now you are saying it can go 4 days. It will be dependent on temperature, humidity, and the quality of the particular capacitor to some extent.

 

[Terry Woods]

ready... fire... aim.

 

[jimbo3123]

Hi,

Has anyone check how long a SLC program (5/04) can last in the CPU without battery & EPROM?

The PLC is not power on.

One of our customer tried and it last for 4 days....and still counting. We go online and upload the program every 2 days and it's still working fine!

Is the capacitor is the backup source for the SLC5/04?

Any feedback...?

Does your processor stay powered-up?
If you're going online every 2 days, then it must be powered at least that often.
Power to the processor will recharge the capacitor and let it retain its memory as well.

 

[TimeFluxCap]

As soon as you lose power to an AB Control Logix and you dont have a battery the program is history! The battery will last with L55M12 for 99 days at 25 deg C.


I just had to look at those numbers for a job.

 

[Unregistered]

Does your processor stay powered-up?
If you're going online every 2 days, then it must be powered at least that often.
Power to the processor will recharge the capacitor and let it retain its memory as well.

Hi,

Yes, the SLC 5/03 CPU is power down before we go online to check & upload the program.