HDMI surge suppression? - AVS Forum
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Old 04-28-2011, 07:05 AM - Thread Starter
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Lighting strike last night took out the HDMI ports on my HT reciever & projector. All other aspects of both components function properly.

This is the Second strike in 2 years that did the same thing. The first time I thought it was a fluke but obviously HDMI doesn't have much tolerance for stray charges.

Are there any recievers that take this into account and protect devices connected to them or would I need something inline?
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Old 04-28-2011, 07:34 AM
 
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Quote:
Originally Posted by rklein View Post

Lighting strike last night took out the HDMI ports on my HT reciever & projector. All other aspects of both components function properly.

This is the Second strike in 2 years that did the same thing. The first time I thought it was a fluke but obviously HDMI doesn't have much tolerance for stray charges.

Are there any recievers that take this into account and protect devices connected to them or would I need something inline?

Unless the receiver was struct directly by lightning, I can't see how an outside surge would be caused by the HDMI line.

However, any line coming from outside of the house, which includes power, coax, telephone, cable, internet, satellite could produce a surge. This surge could then cause a power surge within the receiver or projector, then knocking out the HDMI board and the device.

It is also possible that while knocking out the HDMI board, the surge traveled the HDMI cable. If that did happen, I would expect to see some discoloration on or near the HDMI connector.

Even if the surge traveled the HDMI line, that's still a secondary event. More likely is that both devices took separate surges from the same event. In either case you would be better off making sure *every* outside line was surge protected since that would mitigate the source of the problem rather than a secondary effect. That's also one of the reasons that there aren't many HDMI surge protectors (or a component video surge protectors or a coax digital audio surge protectors) - that's not where the primary problem is. It's the lines from from outside that cause the problem.

However, if you really want an HDMI surge protector, a simple Google search found this:

http://www.firefold.com/%2FFREE-SHIP...SA-P30864.aspx

I have no idea what this will do to a normal high speed HDMI signal. So, buyer beware and I'd make sure that this device isn't going to degrade the high speed signal before purchasing. Also, even if you purchase and install this device, I would still expect that at least one of the HDMI boards would fry if the exact same event happened again. Finally, not all surge protectors are created equal. Make sure you look at the ratings of each to find out how much energy the surge protector can dissipate.
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Old 04-28-2011, 09:01 AM - Thread Starter
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Since both devices were on surge protectors, perhaps the surge protector doesn't provide enough protection for presumably more sensitive HDMI
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Old 04-28-2011, 02:27 PM
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Quote:
Originally Posted by rklein View Post

...would I need something inline?

Best approach is to keep surges out of the building with a whole-house approach that protects all potential surge paths including AC, cable, etc.

Receivers don't do surge protection.

Surge protection of an HDMI connection is problematic. The devices to do it add a small but finite capacitance to each line protected. The problem is that even a small additional capacitance may be enough to upset the signal enough that it is unusable.

The page describing the device Andy mentioned says that it is "active on all...TMDS channels" and doesn't mention the other lines. Only way to find out if it screws up your picture is to try it. But if it doesn't protect all the lines, it is worthless IMHO.

You may or may not see any visible indication of the surge on the equipment.

If all the paths were protected, and the devices connected by the HDMI cable are on separate MOV-based surge protective devices plugged into different receptacles, it may be that is the cause of the damage. There can be a considerable difference in ground potential between receptacles when a surge is shunted to ground.
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Old 04-30-2011, 06:25 AM
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When looking at HDMI surge issues, you need to look from a slightly different angle.
The Ethereal HDMI Surge product was promp'ed by a dealer who called after the entire HDMI chain was damaged (without any issues with the analog or power functions) on a cust. system (note that system was as fully protected as possible).

Since HDMI hardware is (for these purposes) a small computer it is static discharge more than high voltage hits that are the problem. The HDM-SP will clamp up to 8KV in both directions (16KV total) on the High Speed/Clock channels (to date we have only seen one system fail with surge down the 5V/Hot Plug Detect channels and that system had no other protection).

While ANY device added to the HDMI will add loss the HDMI-SP is built with a trace eq'ed, impedance correct 4 layer circuit board (in beautiful Ormond Beach, Fl.) to have as little effect on the signal as possible.

Note; that the original HDMI specs provided for the inclusion of this type of protection but the feature was nixed as product mfgr's complained that it would add too much cost.

The HDM-SP is NOT intented to protect you from a direct hit (very few things will), it will however provide safety from the normal spikes and static discharges.

BTW: Colm's discussion about ground potential needs to be noted, it is always best to bring ALL of your AV power connections back to a single point and circuit and observe absolute polarity at your recepticle's (also do not buy the cheapest duplex device as you have no idea what kind of metal they are built with).

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Old 04-30-2011, 01:16 PM
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Quote:
Originally Posted by Brent McCall View Post

...it is static discharge more than high voltage hits that are the problem.

Yes, that is HDMI's dirty little secret. It is very susceptible to damage from static discharge. It is possible to kill a HDMI port just plugging in the cable.

Based on the description, it sounds like the device used in the HDM-SP is one of the chips developed to protect HDMI circuits from static discharge damage rather than MOVs large enough to handle a true, high current, surge. Can you confirm?
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Old 04-30-2011, 06:38 PM
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You are correct.
It is assumed that the overall system is covered by some type (MOV, Gas Diode etc.) of primary surge protection.
What the HDM-SP is for is a "static discharge" not a direct lighting hit (other devices are for that).

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Old 05-02-2011, 11:10 AM
 
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Quote:
Originally Posted by Brent McCall View Post

When looking at HDMI surge issues, you need to look from a slightly different angle.
The Ethereal HDMI Surge product was promp'ed by a dealer who called after the entire HDMI chain was damaged (without any issues with the analog or power functions) on a cust. system (note that system was as fully protected as possible).

Since HDMI hardware is (for these purposes) a small computer it is static discharge more than high voltage hits that are the problem. The HDM-SP will clamp up to 8KV in both directions (16KV total) on the High Speed/Clock channels (to date we have only seen one system fail with surge down the 5V/Hot Plug Detect channels and that system had no other protection).

While ANY device added to the HDMI will add loss the HDMI-SP is built with a trace eq'ed, impedance correct 4 layer circuit board (in beautiful Ormond Beach, Fl.) to have as little effect on the signal as possible.

Note; that the original HDMI specs provided for the inclusion of this type of protection but the feature was nixed as product mfgr's complained that it would add too much cost.

The HDM-SP is NOT intented to protect you from a direct hit (very few things will), it will however provide safety from the normal spikes and static discharges.

BTW: Colm's discussion about ground potential needs to be noted, it is always best to bring ALL of your AV power connections back to a single point and circuit and observe absolute polarity at your recepticle's (also do not buy the cheapest duplex device as you have no idea what kind of metal they are built with).

Very interesting answer. Thanks for the info - I've learned something today.
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Old 10-24-2011, 12:42 PM
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HDMI and surge.

Surely there must be a solution...

All my devices are connected via HDMI really it is a one connector world.
output=> projector and TV
input=> cable Receiver, Blueray, HTPC, PS3,
Receiver => HDMI in and OUT....+ HDMI splitter

All my devices are on a single surge protector.

About a year ago my second output on the receiver and 1st input on the projector got fried due to lightning... I did not worry to much as i just switch to other ports.

a week ago another lightning problem.

ALL my HDMI ports other then the TV and PS3 is gone.. all inputs and outputs.

all devices work fine as long as connect to composite video output. but HDMI is dead....

Current cost...
Blueray Player >> recycle bin (does not worth to fix....)
Cable Box >> recycle bin (HDMI is integrated to the CPU/MCU) $250
PC >> main board replacement (HDMI was on MB) $200
Projector>> replacement board and workmanship $400
receiver >> new HDMI board is more than $1,100...
HDMI splitter >> Receycle bin $200

just for a lightning... which only damages HDMI ports....

are we really defenseless for this?

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Old 10-24-2011, 11:14 PM
 
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Try this thread and see if it helps you...
http://www.avsforum.com/avs-vb/showt...rge+protection

You have to look at wires that come into your house as the source of the overvoltage. Unless the HDMI cable took a direct hit, these were all secondary effects. You really have to stop the source, which appears to me to be the cable TV box or a roof antenna (if you have one).
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Old 10-27-2011, 05:14 AM
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Thanks to LIPA on Long Island we have problems with electrical surges on a regular basis and all of my equipment is protected or at least I thought it was. Last August a power surge came through the house and I had neglected to protect a powered signal booster on a long hdmi run. It knocked out the hdmi port on my projector and the booster itself but the HDMI port on the receiver seemed to be okay.The cable itself may have been affected as the long run (12 foot plus 25 foot) no longer carries a strong enough signal. I will soon learn if this is the case as I am in the act of replacing it.

Make sure everything is protected.

John
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Old 03-28-2012, 10:26 AM
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Anytime you are getting surge damage the first point to address is the grounding. If the electrical service ground is not below 10-Ohms then anything you do after that to protect will be minimal at best. All grounds should be referencing the same single point reference or you will experience noise, poor picture quality and equipment damage. Once you verify a single point ground reference of low impedance then you can move to the second step... proper surge protection. Most residential surge suppression is garbage. Plug in devices do very little or nothing at all. Remember that the surge suppression installed on electrical distribution panels should have an active transient filter to provide clean power. Most panel-mount surge suppressors are MOV based and therefore will only turn on and address the surge once it has elevated well above the electrical sine wave. That's fine for protecting motors but unfortunately by the time the surge energy has elevated that high your electronics are toast or degraded dramatically at best. The suge experience through the HDMI cable is still being generrated at the AC level and has sifted its way through the amp tot he HDMI port to seek ground. The surge "sees" the ground reference from the TV as separate from the ground reference from the amp. Even though the grounds originate at the same main electrical service, note that the ground conductor from the breaker panel to the receptacle is probably only 14 AWG wire and therefore the impedance (resistance) from that long wire run will change the ground reading between the two pieces of equipment. I recommend Total Protection Solutions surge suppression because they have a proprietary filter that provide computer grade power 24/7 and the best warranty in the business. They focus on large commercial and industrial applications but they have a residential division as well.
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Old 03-28-2012, 10:39 AM
 
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Quote:
Originally Posted by trebor58 View Post

Anytime you are getting surge damage the first point to address is the grounding. If the electrical service ground is not below 10-Ohms then anything you do after that to protect will be minimal at best. All grounds should be referencing the same single point reference or you will experience noise, poor picture quality and equipment damage. Once you verify a single point ground reference of low impedance then you can move to the second step... proper surge protection. Most residential surge suppression is garbage. Plug in devices do very little or nothing at all. Remember that the surge suppression installed on electrical distribution panels should have an active transient filter to provide clean power. Most panel-mount surge suppressors are MOV based and therefore will only turn on and address the surge once it has elevated well above the electrical sine wave. That's fine for protecting motors but unfortunately by the time the surge energy has elevated that high your electronics are toast or degraded dramatically at best. The suge experience through the HDMI cable is still being generrated at the AC level and has sifted its way through the amp tot he HDMI port to seek ground. The surge "sees" the ground reference from the TV as separate from the ground reference from the amp. Even though the grounds originate at the same main electrical service, note that the ground conductor from the breaker panel to the receptacle is probably only 14 AWG wire and therefore the impedance (resistance) from that long wire run will change the ground reading between the two pieces of equipment. I recommend Total Protection Solutions surge suppression because they have a proprietary filter that provide computer grade power 24/7 and the best warranty in the business. They focus on large commercial and industrial applications but they have a residential division as well.

Interesting. I can't disagree with what you wrote on a 6 month old thread. However, I find it curious that within 1/2 an hour you posted three separate appends all saying to look at Total Protection Solutions. Here's the Home Theater section append,

"Anytime you are getting surge damage the first point to address is the grounding. If the electrical service ground is not below 10-Ohms then anything you do after that to protect will be minimal at best. All grounds should be referencing the same single point reference or you will experience noise, poor picture quality and equipment damage. Once you verify a single point ground reference of low impedance then you can move to the second step... proper surge protection. Most residential surge suppression is garbage. Plug in devices do very little or nothing at all. Remember that the surge suppression installed on electrical distribution panels should have an active transient filter to provide clean power. Most panel-mount surge suppressors are MOV based and therefore will only turn on and address the surge once it has elevated well above the electrical sine wave. That's fine for protecting motors but unfortunately by the time the surge energy has elevated that high your electronics are toast or degraded dramatically at best. The suge experience through the HDMI cable is still being generrated at the AC level and has sifted its way through the amp tot he HDMI port to seek ground. The surge "sees" the ground reference from the TV as separate from the ground reference from the amp. Even though the grounds originate at the same main electrical service, note that the ground conductor from the breaker panel to the receptacle is probably only 14 AWG wire and therefore the impedance (resistance) from that long wire run will change the ground reading between the two pieces of equipment. I recommend Total Protection Solutions surge suppression because they have a proprietary filter that provide computer grade power 24/7 and the best warranty in the business. They focus on large commercial and industrial applications but they have a residential division as well."

Looks familiar...
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Old 03-28-2012, 11:06 AM
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Yes Andy, I simply copied and pasted my response to all three since they were all on the same subject. Easier than rewriting each. I thought the same response was applicable to each.
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Old 03-28-2012, 12:24 PM
 
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Quote:
Originally Posted by trebor58 View Post

Yes Andy, I simply copied and pasted my response to all three since they were all on the same subject. Easier than rewriting each. I thought the same response was applicable to each.

Please understand that we get spammers occasionally, particularly with old threads that get resurrected. Glad to see you responded back. Welcome to the HDMI section of the AVSForum.
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Old 08-02-2012, 09:33 AM
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Quote:
Originally Posted by trebor58 View Post

I recommend Total Protection Solutions surge suppression because they have a proprietary filter that provide computer grade power 24/7 and the best warranty in the business. They focus on large commercial and industrial applications but they have a residential division as well.

What is the cost for something like this to be installed into a home?

Thanks,
Steve
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Old 11-23-2012, 05:46 AM
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Since this is still active;

I do understand every singe one explaining the proper surge protection.

I am an electronics engineer and deal with surge, ground loops and many other problems on industrial communications.

I currently live in Singapore on a landed property. At tropics you live with lightning and thunder that's it. But this is not my first experience before Singapore I was living in England suburban area in a house, similar problems when there is lightning. I think i have blown 5 phone modems in my life but that is all lightning could do to me until recently.

Now bit technical

I am personally anal with the ground, earth and Neutral lines.

There is a surge protection on the mains on the distribution board.

In my set up above all the devices are connect to the mains from a single point. (read it as single socket if you like)

This Socket has a Direct Earth, Direct Neutral, Direct Live wire from the switch board.

All the power is distributed from a single distribution socket. Yes, I do bet it is a MOV device. However there is no separate Natural or Earth reference for different devices.

Lightning;
My house did not get hit by lightning, but some where near by did.
Any device that is connected on HDMI, the device HDMI port is gone (blown, burnt) all the devices are working with other input out put ports. EXCLUDING Sony PS3!
Any device that is connected but NOT via HDMI is working.

Hence it does look like HDMI port is very susceptible to surges, much more than other connections we have.

After reading more about this I have found recommendations to manufacturers implementing HDMI standards for surge protection. Sadly this is NOT compulsory, so every manufacturer is saving a 50c per device by not putting these in...

If i can find a way to put optical isolation between my devices i would do this... copper does have its weaknesses.

Any suggestions So I can protect my self from the next blow up?
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Old 11-23-2012, 08:01 AM
 
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You can always go to a fiber optic for HDMI. At least you would only lose one side of the connection.

But, as you said the lightning didn't strike your house and it didn't sound like inductance reached your house. So, how did the surge reach your equipment? Not knowing your setup, it seems to me that it would have to be an attached cable, whether that is power or coax. I've noticed in the U.S. many (most) of these issues are with cable customers. Is there any chance that the surges are coming in your cable and then out the cable box's HDMI line? I think that would explain all of the symptoms. Is your Internet access through the cable as well?
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Old 07-26-2013, 01:30 PM
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I'm now dealing with the second HDMI lightning damage within 3 years. Fortunately, I'm a technician with 45 years experience, so I'm able to replace the HDMI interface chip in the TV again. This time it also took out the HDMI port on my DISH receiver. I've also lost several HDMI switches. NOTHING is getting to my equipment by way of the power line! I have a whole-house arrester on the pole, below the meter, then a Tripp Lite outlet box that boasts $50,000 guarantee for connected equipment, then a Topaz sine-wave UPS, then another Tripp Lite, then another outlet strip with surge suppression. But here's the deal. A very close lightning strike produces an electromagnetic pulse (EMP) that will induce thousands or even tens of thousands of volts into ANY nearby length of wire. In addition to HDMI ports, I've also lost the PS2 port on a computer motherboard, along with the connected KVM switch, several ethernet ports, and an expensive video server. So, what can be done? You can start by using the shortest possible cables. Monoprice has HDMI cables as short as one and a half feet, and they have ferrite cores at each end (which may not help, but can't hurt). Second, you can use a sacrificial device, such as an HDMI switch or an extender/booster. Let the circuitry in these cheap (less than $20) devices take the hit. With luck, they won't pass the spike through to your expensive equipment. I'm not sure whether the power available on HDMI will handle multiple devices, but I'm going to give it a try and will post my results here. As for the surge protection built into HDMI ports, yes, these chips do have it, but the problem is not just volts, but energy. That's volts X amps X time. The chips will protect against fairly high voltage, but not many amps, or not many microseconds. That's fine for static discharge, but lighting induced surges involve a LOT of energy, that can overwhelm the protection that can be built into a chip. MOV's that are used in outlet strips can handle it, but they have lots of capacitance, and cannot be used with high-frequency signal lines, as that capacitance will act as a short circuit to those frequencies. As for the available HDMI surge supressors, as yet the price is just too high for me.
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Old 06-26-2014, 05:33 PM
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Problems with Lightning and HDMI

Hello,


I have experienced the same issues with lightning and HDMI. My house is well grounded and I have a whole house surge protector. I have a 50' HDMI cable running through my attic. A nearby lightning strike can produce a huge magnetic field around the house to the point of producing noticeable static voltages. (I say this from experience because my wife said she felt a static shock in her finger after the last nearby lightning strike.) I have had 2 separate incidences of HDMI ports getting fried after a nearby lightning strike - A mother board HDMI port, 2 TV HDMI ports, an Xbox that completely died even though the power supply was fine and an HDMI splitter. All this with no other noticeable damage.


My guess is that the house surge protector is doing it's job but the long HDMI cable is picking up enough voltage to fry my equipment. It is also possible that the telephone cables in the attic are bringing in spikes that are being transferred to the HDMI cable.


I suspect EM spikes are causing the problem so I am going to try HDMI surge protectors - wish me luck!
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Old 06-26-2014, 10:05 PM
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DIY HDMI Surge Protection

I recently broke down and purchased an HDMI Surge Protector. First thing I did was open it up. For all the money it cost, it was disappointing to see how little was in there. No active components, just about 10 or so tiny MOV's (metal oxide varistors), each smaller than the head of a pin. Total part cost, including the small metal box and connectors, is less than $10. The printed circuit board traces also had zig-zag sections, which is a common method of creating very low value inductors. Considering the very high frequencies involved with HDMI video, this is really about all you can get away with, without degrading the signal. Larger MOV's have far too much capacitance. These are a few picofarads, at most. But it should work as promised, providing that the energy in a surge doesn't exceed the rating of the MOV's. But the bad news is that MOV's this size can't handle much energy. A long cable could pick up enough energy to destroy them. But the failure mode would be to become a short circuit, so it should still protect connected equipment, but the surge protector itself would then have to be replaced (~$150). Sooooo, I've bought some suitable MOV's, much smaller than the head of a pin, and when I get a chance I'll build my own HDMI surge protectors. I'll start by picking up some similar sized HDMI signal boosters, and use the metal boxes and connectors. Then I'll have some pc boards made, and since the boards are very small, I can get a panel of a dozen or so boards for the cost of just one. I'm fortunate to have the skill and equipment to do the surface mount soldering. I will also include fuses, in the form of short pieces of extremely fine magnet wire, which hopefully will blow before the MOV's are damaged, but that may be wishful thinking. If it does work as hoped, a blown device could be repaired in minutes at no cost. Meanwhile, I'd consider using a wireless link to replace a long cable. Chances are that lightning will not damage the link, and your expensive connected equipment should be quite safe.
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