lightning/surge suppression for elk

One of my output relays on my Elk is connected to my driveway gate which is about 200 feet away.   A wire runs underground from my Elk to the gate operator. 
 
 The gate operator control board has been fried before due to lightning strikes, and I know that ethernet cables and phone cables underground are susceptible to strikes.    Do I need to protect my Elk board somehow from getting fried by a surge traveling up the wire to the Elk?

It would be a very good idea to put surge suppressors on any cables coming into the house.  Power wires should also be protected.
 
For a single output on the M1, the Ditek DTK-1LVLPX is a good choice if its operating with 12V.  They also have other models with different voltage ratings for things other than 12V circuits.
 
Ditek also makes many different models that can handle multiple pairs if you need that. 
 
The suppressor should be mounted where the cable enters the house, and you should ground it with as short a wire as possible to your ground system.  A wire directly to your home's ground rod would be best, rather than using the ground wire in a nearby outlet.

RAL said:

It would be a very good idea to put surge suppressors on any cables coming into the house.  Power wires should also be protected.
 
For a single output on the M1, the Ditek DTK-1LVLPX is a good choice if its operating with 12V.  They also have other models with different voltage ratings for things other than 12V circuits.
 
Ditek also makes many different models that can handle multiple pairs if you need that. 
 
The suppressor should be mounted where the cable enters the house, and you should ground it with as short a wire as possible to your ground system.  A wire directly to your home's ground rod would be best, rather than using the ground wire in a nearby outlet.

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Thank you!  
 
So, does this go inside a box or inside the house?
 
Also, should I have a second one at the gate controller board to protect it from getting fried again?

hgupta1 said:

So, does this go inside a box or inside the house?
 
Also, should I have a second one at the gate controller board to protect it from getting fried again?

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You can place it in a weatherproof box outside the house, just before the wire goes through the wall, or inside, right after the wire enters.  The goal is to divert the surge before it travels further into the house.
 
It's a good idea to place a second surge protector at the gate end.   There, you can drive a ground rod for the ground connection.

This is incredibly helpful.    I never really thought about surge suppression, but I have already spent more on fried electronics than these things cost.  
 
I see that Ditek has a lot of different versions based on the voltage.     To figure out which one I need, do I just measure the voltage across the contact closure at the gate?  Or is there anything else I need to account for.

hgupta1 said:

One of my output relays on my Elk is connected to my driveway gate which is about 200 feet away.   A wire runs underground from my Elk to the gate operator. 
 
 The gate operator control board has been fried before due to lightning strikes, and I know that ethernet cables and phone cables underground are susceptible to strikes.    Do I need to protect my Elk board somehow from getting fried by a surge traveling up the wire to the Elk?

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Outside things can be a big problem. Yes surge suppressors, but if you are just controlling a gate with a few outputs, why not optically isolate it.  You can buy these optical isolators cheap.  If lightning strikes, the worst is you will have to replace a $5 part.  Grounding, especially with outdoor segments is really complex. Your best option is to isolate it.
 
For $9 you can isolate 4 channels. Cheap insurance.  https://www.amazon.com/NOYITO-4-Channel-Optocoupler-Isolation-Photoelectric/dp/B07GMHLL2M

ano said:

Outside things can be a big problem. Yes surge suppressors, but if you are just controlling a gate with a few outputs, why not optically isolate it.  You can buy these optical isolators cheap.  If lightning strikes, the worst is you will have to replace a $5 part.  Grounding, especially with outdoor segments is really complex. Your best option is to isolate it.
 
For $9 you can isolate 4 channels. Cheap insurance.  https://www.amazon.com/NOYITO-4-Channel-Optocoupler-Isolation-Photoelectric/dp/B07GMHLL2M

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I didn't even know that was an option.   Does that just go inline between the elk and gate operator?    Will that also work for input sensors (magnetic reed switches) that tell me when the gate is closed, or is it limited to outputs?

hgupta1 said:

I didn't even know that was an option.   Does that just go inline between the elk and gate operator?    Will that also work for input sensors (magnetic reed switches) that tell me when the gate is closed, or is it limited to outputs?

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Optoisolators are good things to use as a way to protect systems.  The one Ano linked to is one example. The optoisolator on that one has an output that is an open collector transistor with a 3k series resistor which may or may not work directly with your gate controller.  Instead, you could use an optoisolator relay board which will give you a dry contact output like you have now.   One other thing is that these optoisolator chips only provide 5kV of isolation, which may not withstand a nearby lightning strike.   Using a surge suppressor would still be recommended.
 
Also, an optoisolator can't help you with power supply wires, so you still would want a surge suppressor on those.  Not sure if you have low voltage power from your house running outside in this case.  Might not be a concern then. 

RAL said:

Also, an optoisolator can't help you with power supply wires, so you still would want a surge suppressor on those.  Not sure if you have low voltage power from your house running outside in this case.  Might not be a concern then. 

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Thank you!  The gates use 120V power.  These were already here when I bought the property.   Is there any sort of additional protection I need here?  There's actually quite a few 120V runs outside going to fountains, lights, and outlets as far as 300 feet from the house.    I've been thinking of getting a whole house surge protector installed when I get around to getting a generator installed..

A whole house surge protector is definitely worthwhile.  This Eaton CHSPT2ULTRA model is an excellent one to consider. There are also similar ones from other manufacturers, like Leviton.
 
You can also put additional surge protectors on each individual circuit that runs outside. Ditek also makes 120V models.

Here's a good article on the subject.
 
https://www.stevejenkins.com/blog/2014/10/whats-the-best-whole-house-surge-protection/

RAL said:

Optoisolators are good things to use as a way to protect systems.  The one Ano linked to is one example. The optoisolator on that one has an output that is an open collector transistor with a 3k series resistor which may or may not work directly with your gate controller.  Instead, you could use an optoisolator relay board which will give you a dry contact output like you have now.   One other thing is that these optoisolator chips only provide 5kV of isolation, which may not withstand a nearby lightning strike.   Using a surge suppressor would still be recommended.

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The optoisolator relay board arrived today.   Of course, it didn't come with any instruction.  This is going to seem like a dumb question to all of you pros, but how do I connect this in between my elk output relay and the gate dry contact? 

hgupta1 said:

The optoisolator relay board arrived today.   Of course, it didn't come with any instruction.  This is going to seem like a dumb question to all of you pros, but how do I connect this in between my elk output relay and the gate dry contact? 

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Connect the DC+ and DC- terminals to the Elk's +VAUX and NEG terminals, respectively.  
 
Connect the IN terminal to the Elk output that you want to use to control the gate (e.g. Out16).
 
Then connect the COM and either the NO or NC terminals of the relay to the gate control wires.  The NO terminal will short to the COM terminal when the relay is energized (i.e. the Elk's output is on).  The NC terminal will short to COM when the relay is not energized (i.e. the Elk's output is off).

It looks like there is a jumper for setting either a Hi or Low trigger.  For the behavior I described above, set the jumper to Hi. 

thank you!