Fred Mau
Lifetime Supporting Member
Cleaning off a shelf, I find a Modicon PC-A984-120. CPU only, no backplane or aux memory card or anything else. It's probably been there at least 10 years, and nobody knows anything about it or where it came from (We're a Siemens shop).
Out of curiosity, I connect 24VDC to the 24VDC +/- terminals on the front. Nothing. No LEDs light up, nothing.
From that, should I assume it's a dead piece of junk? OR is it just not going to come alive unless it's on a proper backplane?
Out of curiosity, I connect 24VDC to the 24VDC +/- terminals on the front. Nothing. No LEDs light up, nothing.
From that, should I assume it's a dead piece of junk? OR is it just not going to come alive unless it's on a proper backplane?
