Grounding Issue With Panasonic WV-SW396A

This is a new issue for me. I'm hoping someone has some advice.

I have a crew in the process of installing Panasonic WV-SW396A cameras where the cameras refuse to pull POE over a Panasonic branded 802.3AF injector, but only under a specific situation. This occurs in 6 out of 7 PTZ locations. A PWM30G mount is being used.

1. Panasonic IEEE 802.3at injector does not provide power to camera when installed on PWM30G. A third party 802.3af injector works fine. The decreased wattage will not enable the heater to function.

2. The camera functions perfectly with both 802.3at and 802.3af injectors both indoors and outdoors as long as it is not mounted to the PWM30G bracket.

3. We have narrowed down the culprit to the the Panasonic PWM30G mount. The camera functions perfectly when mounted, but the second the bolts are inserted into the mount to hold the pipe with the 90 degree bend all POE drops.

Clearly this is some form of grounding issue with the camera/mount. The camera only has a Cat6 cable ran to it. I have torn into the top housing and see it uses the housing as a ground in two locations. The housing is nearly all metal as is the PWM30G.

At this point we're looking at nylon bolts to keep out the metal to metal contact on the components of the mount. Any other options?


Where does the injector ground to?

Good question! It grounds at the IDF through a 3-pin 115v power supply adapter. The injector is a Panasonic PPOEP01i01 which appears to be manufactured elsewhere and is entirely undocumented.

We have also tested out an Altronix Netway 112 which works but is 802.3af only. It required an external power supply which was 12v and ungrounded.

We also tested a Altronix Netway 1D which does not, but is 802.3at. It does have a three pin 110v direct input.

Soo... ground lift adapter?

I don't see harm in trying it, and may even 'work', but I suspect there is some other element involved, since the DC power of PoE is normally electrically isolated.

For instance, is the cable shielded? If so, is it earth bonded at one or both ends? Or to the spare pair?

Is the mount grounded for surge/lightning protection?

What's different that you see on the 1 out of 7 units that does work?

For instance, is the cable shielded? If so, is it earth bonded at one or both ends? Or to the spare pair?

It is not shielded.

Is the mount grounded for surge/lightning protection?

It is not. Not a common issue up here.

What's different that you see on the 1 out of 7 units that does work?

Not much:

1. Shorter run, perhaps 75'.

2. It's on a UPS, the others are not.

In trying to diagnose this we ran an extension cord from a nearby outlet inside the building directly to the camera location. We then hooked up the injector and used a 7' patch cable right at the camera. The camera/injector works fine... until the bolt is put into the pole extension, making metal on metal contact with the mount.

That seems strange. Maybe you could see with an ohmmeter if there is continuity between the grounding prong of the injectors AC plug and any of the conductors of the POE cable. With the injector unplugged of course. :)

I don't think there should be. I'll check one of mine, after dinner..l

I agree that checking the housing for continuity is a good step. You could try to wrap the existing threads with teflon pipe tape just to see if it influences the issue, but the long term fix if the mounting hardware/brackets are hot is unit replacement, not pipe tape.

Electrically isolating the mount using tape appears to work. The manufacturer is looking into possible causes.

It looks like using electrical tape to isolate the mount surfaces works on two units so far.

1, I can't say that this is a satisfying outcome. Not that there aren't times when this could be ok, but, frankly we don't really understand WHY this works.

What you are doing by isolating the mount is giving lightning (unlikely perhaps) no other path but the cat cable all the way back to the building.

I would at least make sure a licensed electrician signs off on this.

they dont run on AF only AT (I.E) PoE plus. they will run on PoE .AF with run less than 50ft but other than that you should be using PoE Plus especially with the housing

also as you turn the mount some times you can twist the cables and they lose connection . no the best design i agree but the spec sheet recomends WV-Q122 bracket because of that issue

Edit because of fat fingers

Surprisingly, the camera does power up under 802.3af. If the heater kicks on I imagine it is likely to shut down or reboot. However, when I said 802.3af in the initial paragraph that was a typo. We did however test out an 802.3af injector which did work. The whole debacle has been very odd.

yes as I said before the will try to power up with in about 50ft of the PoE souce on AF but any longer than that they will just cycle never fully booting up. I have had problems with auto-sensing 802.3af/at PoE injectors,midspans and switches normally i have to use a straight 802.3AT all the time injector/midspan to keep the PTZ's from doing what you have going on.

That i have have had to repair the top part of where the wires go into the PWM bracket. the installers had to screw the camera onto a threaded mount and damaged cables by twisting them to much. kinda unlikley becuase you said you used the though bolt instead.

Are the mounts attached to anything with this or are you holding them together in your test area ?

The WV-Q122 is not sold in the US, only in Japan and certain other countries.

As a side note, if you are running PoE+, make sure that LLDP is enabled on the switch. Some Cisco switches you have to turn off CDP first.

Um no I can buy the WV-Q122 here though a distributor here in the US my price is about $200 infact i have it on contract price.