Re: Ground Loop challenges

[Bob La Londe <none@xxxxxxxxxx>]

On 1/21/2018 6:36 AM, ABLE1 wrote:
> On 1/21/2018 4:36 AM, doug wrote:
>> "ABLE1" <someone@xxxxxxxxxxx> wrote in message
>> news:9jO8C.314017$%g5.8315@xxxxxxxxxxx
>>> Hey Guys!!
>>>
>>> I have a camera install that is plagued with Ground Loop issues.
>>>
>>> I have been installing individual BNC Ground Loop Insulators on
>>> individual
>>> cameras that are the worst which cleans up the video for that camera.
>>>
>>> However, over time another camera gets bad, and then another, etc.
>>>
>>> As I understand the problem is due to an imbalance in voltage at 60
>>> cycles
>>> or ground reference between phases from the power company. And that the
>>> video is very sensitive to the imbalance and causes the video bars, bla
>>> bla bla.
>>>
>>> My questions are as follows.
>>>
>>> Is there a something device thingie that can be installed at the breaker
>>> panel across the phases that can blend or sync the cycles, etc.??
>>>
>>> Is there a something device thingie that has more than one individual
>>> port
>>> that can be mounted at the head end (like a 8 or 16 port) that can
>>> isolate
>>> the ground loop with out using all the dongles??
>>>
>>> Thanks for any insight!!
>>>
>>> Les
>>
>> Is this coax or cat 5 using baluns?
>> Are the cameras 12vdc or 24vac?
>> Are you using a single power source or individual power sources for each
>> camera?
>>
>> Doug
>>
>>
>
> Sorry, I forgot to mention that important info, brain was not totally
> activated.
>
> There is a single power source 120vac for everything with two 16 channel
> 24vac power supplies for the cameras.
>
> A few cameras are 24vac but most are 12vdc with a step down inverter at
> those cameras.

I thought an inverter turned DC into AC.  I had bad luck with those
AC/DC converters on cameras a while back, and never used one again.  I
have used several cameras that were AC DC auto switching internally that
seemed to work just fine, so maybe I just had cheap converters.

I did try a fairly expensive multi tap ground loop isolator at the DVR
once a long time ago.  It worked but all the camera feeds were grey and
dim.  Loop termination on and loop termination off at the dvr.  Both
were the same.  I went to cheap single line ground loop isolators at the
cameras after that and they seem to work just fine.