Remote I/O Analog - do you use "blue hose" for analog I/O?
Many Allen-Bradley PLC-5 processors are now being upgraded to use newer ControlLogix processors – while still keeping in place (at least temporarily) the plant's reliable old "1771" style I/O hardware - and all of its installed wiring.
At the ControlLogix end of the line, a 1756-DHRIO "bridge" module provides a means of connecting the existing cables (known as "blue hose") to the new controller system.
This common situation presents some serious challenges to the maintenance crew – especially where the older "1771" style analog input and output modules are involved.
This is such a common arrangement, that each student in our Boot Camp classes will set up a DHRIO module through a series of hands-on exercises on Monday afternoon.
Reference material on Allen-Bradley's website for 1771-ASB
Reference material on Allen-Bradley's website for 1771-IFE
© Copyright - R.H.Beaufort - Charleston, SC – Updated: October 29, 2013