What is you surge suppression experience

That is a reasonable question.  Another IT guy would probably read any notes you have on the AP or network map.  To everyone else... connectivity is magic.  Even if you tell them, they will forget.  SO... The label maker may seem like an old guy thing BUT... it works.  Slap an "Isolator Installed" label on the AP and PTP cable ends.  Sometimes, in the heat of the moment, even we forget stuff.  A little reminder can help a lot.

For the isolators we installed, they were physically close enough to the equipment that their existence was reasonably obvious.  They also have a data tag.  If a technician couldn't figure out where to go from there... I didn't want them working on the equipment anyway.  Rude?  Maybe.  Back to Troubleshooting 101, right?  Is it receiving power?  Is it receiving input?  As I taught my techs... No gozinta = no gozouta.  (Goes in to / Goes out of).
The reality is that, most of the time, they figure it out.  - unless you keep rescuing them. 

Hi Sean,

I was googling and found this product which looks interesting: Citel MJ8-POE-C6A

The datasheet has this diagram:

I've never seen three-terminal GDT's before, but the Cyclone product you found uses three-terminal ones too. However, the MJ8-POE-C6A also includes a lot more.

This is the Cyclone circuit from their datasheet:

The Citel one has a shielded metal enclosure, plus also has silicon devices (for faster action; the GDTs will be slower) for differential-mode within each pair, but also between two pairs. Not sure why the two central pairs in that diagram don't have the same arrangement, anyone know?

Also, I was wondering, it might be a good idea to buy ferrites too, and clip them at each end, to suppress common-mode spikes, so the diodes and GDTs have to do less work. They would have to be quite large ferrites.

I bought these a while back:

I wasn't planning to use them for network connections, but because I wanted to fit an antenna outdoors and was worried about induced voltages during thunderstorms. 

The different pairs is because of the standard, the network pairs are 1-2, 3-6, 4-5, 7-8 with only the first two used in 10/100 configuration.

These look interesting; three-terminal GDT from Littelfuse, but in SMD format which should be better, probably easier PCB layout with these too.

Also, reading more, apparently another path is through the mains supply to your network equipment, because any lightning strike to earth will create a huge voltage difference in earth, and that means that the line+neutral can become temporarily at a massively different voltage to local earth or to earth near your Ethernet cable. Just a few picofarad capacitance to ground will therefore cause massive current to flow. There are DIN mount surge protectors for the mains. I don't know anything about these, but hopefully an electrician may know. So, a holistic approach may need the surge protection on both the mains entry (and check it has line/neutral to Earth protection, not just line to neutral like cheap mains extension surge protectors) as well as the surge protection at the Ethernet cable (both ends, and ideally with TVS as well as GDT) and add large ferrites at the Ethernet cable (both ends) too.

Total speculation however.. this is well outside my comfort area : (

Also maybe worth considering optical if possible : )

Hi cstanton if colporteur is Ok with it, please could this be turned into a blog rather than forum discussion? I think it could benefit from more visibility so experts coming across this can provide some advice for all : )

Hey Shabaz,

To get the best visibility, it may be better to be additionally written up as a blog post separately to this forum thread, and then it can contain member quotes and replies, rather than converting the forum thread to a blog post which may then hide the comments.

Hi,

First, to put it simply: I highly recommend a fiber optic cable connection.

Why?!!!! -> Because you have two major problems, plus a few other minor issues that also play a role.

1) Lightning strikes
2) Different grounding potentials between the buildings.

1.a) Lightning strikes can NEVER be intercepted with just a single component. That's the "minor" issue I was referring to.

Please look here at Eaton, USA (I use this in EU, Austria):

https://www.eaton.com/us/en-us/products/backup-power-ups-surge-it-power-distribution/surge-protection.html#sortCriteria=%40p_navigation_title%20descending%2C%40page_title%20descending%2C%40title%20descending&f-product_attributes_product_status=Active&enableQuerySyntax=true&cq=%40sub_category_id%3D%3D%22surge-protection-devices%22%20AND%20%40country%3D%22us%22%20AND%20%40language%3D%22en_US%22

So, the building needs a foundation grounding system, which is driven very deep into the ground in the center.

There are regulations regarding whether there needs to be one or more of these; this depends on the size of the building site.

You've roughly illustrated the extent in the video, about 300m on each side, approximately...
Therefore, also because there are several buildings, multiple foundation grounding systems are necessary; depending on the size, two or three.

This also depends on where the power source is located and where the transformer is situated.

The point is:

The power lines, in this case the lightning strike from where it would originate, create a voltage cone. Within this voltage field, the building's infrastructure, and even living beings with their step voltages, can be affected.

Therefore, first, the building must be protected with a lightning rod. This lightning rod already dissipates a significant amount of energy.

Second, the building needs surge protection for the three-phase power supply in the distribution box, directly at the inlet of the power line, along with an RCD (residual current device) and fuses.

With this surge protection, you can also install filters if a modem is installed that transmits data over the power line.

Third, surge protection devices for the equipment are then installed in the building, for example, as you showed in your post.

For the building, it is crucial that the protective earth conductor (PE) is very well connected to the foundation earth electrode, located at the bottom of the building on the equipotential bonding bar.

For the building, it is important that the protective earth conductor (PE) is very well connected to the foundation earth electrode, which is connected to the equipotential bonding bar at the bottom of the building.

The better these buildings are connected to the ground, the better the grounding potential between them. The lower the grounding potential, the better, ideally less than 2 volts.

The problem is minimized between buildings when you need to run data cables; underground is better than above ground.

The shielding of the LAN cable then acts as a ground conductor because it's connected to the protective earth (PE). Be careful not to create a ground loop.

Precisely for this reason, I recommend using fiber optic cable instead of copper cable.

Since you need power and LAN in all buildings, you can use fiber optic cable as the "backbone." The LAN cabling infrastructure is then located within the building.

Strictly speaking, this would eliminate the need for a wireless setup. In my experience, wireless LAN has its own set of problems, mostly related to weather conditions. Whether fiber optic or wireless, you'll need to use data converters in both cases. So, the effort involved is comparable. Fiber optic cables might be a bit more expensive to install, but after that you practically have no problems, unless an excavator tears the cable off, or the laser diode weakens after many years.

This was just the first thinking about, ok.

In the 1990s and 2000s, I offered these devices at my company as an electronics technician. Later, I was an electrician for the railway. Now I'm retired.

If you like, you can post here some details of your project.

Best Regards

Gerald

Hi Gerald,

Very useful information!

colporteur said:

gibt es GPS-Antennen und Kameras.

GPS? shure? Or are they WLAN-antennas?

All these buildings needing a potential ground system, a lightning rod from the roof to the ground.

What's in the Silos?