By security engineer, can we assume you mean alarm (and peripheral) installation?
It may sound a silly question, however, did you use Cat5e/Cat6 cable? - I have seen an alarm tech use 8 core alarm cable!
Secondly, what pinout did you use? What colour on what p? Which standard? and did you check the pin numbering on te IDCs? They are NOT always a straight 1-4 & 5-6. I did some Knone ones which which go 2,1,3,5,4,6,8,7 and they were replacing a different brand which were 6,3,2,1,7,8,5,4
M H C
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