Iam replacing a faulty SLC5/04 CPU Unit [1747-L541, SER C]. The Spare Unit I have got is 1747-L541, SER B. Any advice from experts there whether this will work ?
OTOH, if all you have available is a Series B, just put it in, and see if it works. What's the worst case outcome: its still broke, and you buy the exact replacement.
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