ControlLogix 1756 Series A and B

Hello,

The A-B 1756 components have series A and B. What is the different of the two ? can I use 1756 series A chassis with series B CPU or other modules ?

Thanks

If you are talking processor, series B 1756-L6x processors have non-volatile memory, but series A processors have volatile memory. Series B processors should not lose their program if the battery dies.

I believe the only difference between the series A and B chassis is the increased current carrying capacity. That should be the only thing to watch out for when using the old series A chassis
http://rockwellautomation.custhelp....F9zZWFyY2hfdGV4dD1jaGFzc2lz&p_li=&p_topview=1

Series A processors drained the batteries FAST! We saw those batteries drain within a couple of days when power was off. So they came up with a big, huge, honkin' external battery to help compensate for that, but it wasn't much better. With our recent ice storms around here, there have been places where the power was off for over a week! With Series A processors, I would have had to reload many of those programs.......

Series B processors have internal non-volatile memory. When power is removed, the battery is used only long enough to store the program and user memory to the NVRAM, then the battery is turned off -- it lasts forever this way!


Yes, you can interchange the racks. As TW mentioned, you just have to watch the current loads.