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Hi
guys, Regarding
the above subject: I
have more information from 4 test houses: Regarding
the question, how may Switches are using ALT B for powering the answers that I
got so far are; UNH:
40%. It is no sufficient information since there are more then 100 different
brand names for Switch. (Even much more) so it is not clear to us how many used
ALT B from How many tested? So it cold be 4 out of 10? I don’t know. Source
#2: out of average of 40 brand names, 5% used ALT B. Source
#3: Out of average of 20 brand names, 2% used ALB B. Source
4: Similar to source #3. Now,
I belive that the above data will be less important if we first check what
possible issues we can have from this input. From
preliminary analysis I see the following: If a Switch which power on ALT B connected to a
Midspan that powers also on ALT B then according to the specification the
Midspan will power and the Switch will not which is OK. The reason is that Midspan required to prevent
backward powering so the there is no DC path between Midspan and Switch, only
AC path. Therefore I don’t see problem here.. In addition Fort the last 8 years I didn’t
received any complains regarding this combination. I have check other permutations, so far didn’t
find new problems. If you see one please share with us. Yair
Analog Mixed Signal Group Microsemi Corporation
Cell: +972-54-4893019 E-mail: <mailto:ydarshan@microsemi.com>. |