Dropping Cameras Strange Problem

I have put 4 cameras at a checkpoint all within 20 feet of poe switch they are hikvision domes and are 6 mp each. The issue is for no reason one or two randomly will drop of switch and i can see it loose connection on switch locally. i have disconnected the fiber to main recording site until i solve present problem. I have tried a different switch and changed rj45 connectors on cable thinking it was a bad crimp,but not the case. The 4 cameras will connect after mutiple retries on disconnect from switch and finally will hold for couple of minutes. Its on a cisco switch now with fiber gbic for remote monitor and record. I have tried a inaxys which i use faithfully for some time,same results. I have some of these 6mp hiks at different site with no issue. Spoke with tech assist and they could only offer turn down resolution as i could be over taxing switch. I will try it tomorrow but im kinda skeptical.

If there is just one on the switch will it work indefinitely?

Yes seems mutiple cams on switch cause problem becuase say i have 3 connected and the fourth will just give me poe light and not lan light and then i put it on a different switch by itself it will connect .However i didn't see how long it would hold for.I will have use 4 of those midspan poe units from axis i have on hand to see if independent units will keep connection stable.

IMHO, sounds like a power shortage. I would say an IP conflict, but even then you will get a LAN light.

Whats the exact model numbers involved?

The model are ds-2cd-4324 and 4526.1st being 2mp and 4526 is 6mp.Definately not ip conflict ,ip's are .I noticed tonite all lamps poe and lan are on but only 3 cameras working so problem seems to be pointing to switch.I will try tomorrow to put 2 cams on one switch independent and see what happens.

What is the model of the switch? How much PoE power max does it supply?

One theory is that the switch cannot supply power to all cameras, causing cameras to go offline intermittenly when power is maxed out.

John i think you may be on to something becuase i have used the exact units before with no issues.I am in process of running separate power to each camera so will update everyone.I know i split cameras to two switches and i saw a lot of improvement.I was going to try those midspan 60 watt units but i be robbing peter to pay paul.I think a poe+ would do it.

I found out from Hikvision that 2cd4332 and 2cd4312 cameras will run on standard POE. The 2cd4324, however, requres POE+. I bet it is the same with the 6MP model. You probably do not have a POE+ switch. Check this and the power budget for the switch.

Update on dropping cameras feeds.I found that with ivms4200 cameras didn't drop but with exacqvision vms they did.I connected locally and only once in two days did it drop.Actually it was this issue that led me kinda in wrong direction for few hours.The problem almos entirely disapperared when i split cameras into two switches.Anyway today i ran independent feeds of 24 vac to all cameras and all issues went away.The switch was 60 watts but couldn't handle these particular cameras.Incidently i had poe+ switches on order.Thanks for help.