Ground Loop Issue?

[Fahad Abrar]

They are not dual voltage.

I think I will check all the power connectors, it could be that one of the connectors has reverse polarity and probably bring the equipment back into to lab for some more testing. If the lab tests are ok then we know its the wiring and definitely a ground loop.

[Hillbilly]

I realise it will be a pain but if you try powering the cameras up from a battery to see what pictures you get at the monitor side.

[Fahad Abrar]

So to summarise I see the following might the issue and these are the things that can be done:

 

1. One of the cameras may be on reverse polarity

2. It doesn't seem like a ground loop issue, however as I said that I can feel the tingle when I touch the BNC connectors at the back of the DVR.

3. I should bring the equipment back to lab and test it.

4. Most likely to be a power issue, however I have tested with a bigger boxed 10A supply but the same problem persists.

 

Please advise if I am missing some points.

 

Thanks

[al-yeti]

It's possible you have a potential on the earth in the building have seen this before , it was resolved by correcting a fault in a socket , however tingling on the bncs maybe a side issue, as those lines or bars or whatever we call them "shouldnt" cause that , maybe it's the power unit, I have seen toroidal transformers cause this in a similar way

As above stick a battery on them and see what happens , if DVR is 12v input then even easier you can stick it all on a battery

[Alpat Systems]

What BNC connectors are you using?

TVI can be very fussy with the BNC termination compared to "old style" analogue.

Make sure when terminating the BNC that the foil shield and braiding on the cable is cut back so its well clear from the centre conductor/pin. You don't normally have to worry about this so much with analogue but I've witnessed a similar fault to what your describing.

Just for test purposes try connecting the camera to the DVR using CAT5 and baluns

Edited March 16, 2016 by Alpat Systems

[Night Owl]

Second above, be extremly careful with the braid and core, happened to me only last weekend!

 

Won't be reserve polarity as it would stop the other 3 from working. That looks like cabling issue, and if you've used that cabling before i'd point my finger at connectors.

 

Have you tried sending a pattern down it? If so what are the results?

[Fahad Abrar]

What's a pattern?

[james.wilson]

What's a pattern?

test pattern out of ur test mon

[al-yeti]

Well depends how old your are jw old pattern gens didn't have a monitor lol

[Fahad Abrar]

Lol