Tag Archives: HDMI

How To Protect HDMI Inputs From Being Toasted By Lightning

Protect HDMI Inputs


So you have a super duper Home Theatre system complete with a jiffy HD Projector and a top-of-the-line AV Receiver linked by a 50-foot (15-metre) HDMI cable that snakes overhead in the ceiling. One end is connected to the HDMI input port of your overhead HD Projector while the other end is connected to the HDMI output port of your AV Receiver across the room.

What happens when there is a severe thunderstorm and there is one or more lightning strikes nearby? Does your system go on the blink? If yes, then you share the same bad experience as I have. The close proximity lightning strike has induced a large voltage spike  in your long HDMI cable that completely toasts your HDMI ports. If you’re “lucky” then maybe only either the Projector’s or the AV Receiver’s  HDMI port gets toasted. More likely, both will be zapped.

After that has happened to me 3 times in as many years, I decided to be proactive as I was getting embarrassed submitting my home insurance claim every year. Not to mention the inconvenience of the downtime pending repairs. I installed my solution early this year and having survived 2 severe thunderstorms since the installation, I am confident this is a viable solution to protect HDMI inputs from being toasted by lightning-induced spikes in the long HDMI cable of a home theater system. Read on.

hdmi-switch protect HDMI inputsThe solution calls for two HDMI Switches. I searched for a simple 2-to-1 HDMI Switch but the simplest I found is this 3-to-1 HDMI Switch. I wanted a mechanical switch but finally settled for this electronic switch because it has a remote. This makes the switching convenient when the switch is mounted at the Projector, ceiling-high.

AV-receiver-hdmi-switch protect HDMI inputsInstall one of the HDMI Switches to the HDMI Ouput of the AV Receiver. In my case, I connected Port 3 of the switch to the AV Receiver’s HDMI Output. The switch’s output port is then connected to the long HDMI cable. The other end of the HDMI Cable connects to Port 3 of the second HDMI Switch mounted projector-hdmi-switch protect HDMI inputsat the overhead Projector. The output port of this switch connects to Projector’s HDMI Input port. That’s it. When the system is on, I use the remote to switch to Port 3 of both switches. When I have finished viewing, I switch to the un-used Port 1 of both switches, before shutting down the system.

The cost? Only RM80.00 (USD24.00) for each HDMI Switch.  I reckon that in the event of a really bad lightning strike, it’ll be a USD24 fuse. But so far, neither switch has failed.

Does this help you? Share your experiences here.

Update 10-Nov-2014

Last night there was no video output from my Projector. The bulb was OK but there was no display. A quick change of the HDMI input port from HDMI 1 to HDMI 2 was to no avail. A quick visual check showed that the light on the HDMI switch at the Projector went out, like there was no signal reaching it from my AV receiver. Checked the HDMI output from the AV receiver; there was output when connected directly to the TV. It appeared as if either one or both of the HDMI switches were toasted, but when swappped out to test each at the AV receiver end showed both were OK. Horrors! Could it be that my projector’s HDMI ports are both dead? I refused to believe that; if anything, the HDMI switch should be toasted first. I am confident of that. That left one long shot to try out. Maybe the signal from the AV receiver had somehow degraded and was a trifle bit too low at the Projector end?   Luckily I have a HDMI repeater. I connected the HDMI repeater to the Projector end of the long HDMI cable before connecting to the HDMI switch. Voila! Happiness! Problem solved.