Fire! Fire! Sparks!

[reishka]

About a year ago, I started a project to make a multi-touch table. It used a short-throw projector and some mirrors, IR LEDs, modified cameras, and specialised software. Once I made the proof-of-concept, it sat in our living room for four months while I was in school. Since we weren’t doing anything with it, I tore it down and stowed the pieces.

A few months after that, my husband and I decided to create a very nice entertainment setup. We cribbed the short-throw projector from the touch-table project, purchased a ceiling mount, and a 100-inch ceiling-mounted projection screen. We also decided to purchase a low-end home theatre system.

So, let me take a moment to explain our home theatre system. We have three devices: A PS3, an XBOX 360, and a cable box. We also occasionally connect a computer or laptop into the system so that we can play games via Steam on the projector. What I wanted to do (eventually), was mount a small television in the kitchen, so that while I’m preparing dinner I could stream Netflix or watch the news without having to turn the living room television volume up to insane levels. I also wanted a setup where my husband could play video games in the living room while I’m in the kitchen watching the news. So it was a key point that we couldn’t just use a splitter: a splitter duplicates the signal across both outputs of the device. We needed something that would take multiple inputs and output two different signals. We also decided that the living room TV and the projector would duplicate displays, since chances were that if we had the projector on, we wouldn’t be watching the living room television.

So, in the end, we settled on a Kinivo 4×2 matrix. It’s a pretty nifty device. It can take up to four inputs and output two different signals. So, for example, if the cable box is connected to port 1 on the matrix, and the PS3 is connected to port two, we could output the PS3 to the living room TV and the cable to the kitchen TV (or vice-versa) at the same time. It’s pretty much exactly what we needed. We called an electrician to install an outlet in the ceiling, and I got started wiring my system together.

Entertainment System Diagram

The only thing that we outsourced was the electrician — I don’t know nearly enough about mains power to be safe. So the electrician ran an outlet, and I ran an HDMI cable through the attic and down the wall according to code; I also ran the speaker wires, and wired all the components together. The setup was pretty perfect… we could play games on the Projector or the living room TV, the surround sound worked fine. Every once in awhile, when I would connect my laptop into the system there’d be tiny little white sparks, but I chalked that up to static cling discharging…

… Until last Saturday. Last Saturday was a trip and a half. Last Saturday, I was in the process of connecting my PC into the system so that I could play some games while waiting for guests to arrive (it just so happened that last Saturday was also our monthly ‘Saturday Night Game Night’). A few guests had already shown up and we were chatting away while I hooked the HDMI cable from the matrix into my PC.

The next thing I know, someone is screaming “Fire! Fire! Sparks!”. I immediately yanked the HDMI cable out of my PC and shut it down. I then shut off the power to the entertainment system and it’s various components, while a friend put out the fire. As it turns out, the HDMI cable that ran from the projector to the splitter caught on fire! There were sparks coming from the HDMI devices that were connected to the matrix, so that was our first culprit. We also suspected the splitter, based on the multimeter readings. Any HDMI port that was connected to the system was completely toasted (except, interestingly, the home theatre receiver — that’s the only device that escaped unscathed). Over the course of the week,  I’ve spent hours talking to customer service about appropriate multimeter readings, ordering replacement parts, getting equipment repair quotes, and setting up RMA orders. In the course of talking to a tech from Kinivo, he recommended we get the outlet checked. So I called up our electrician and had him come out.

So he comes out. A quick test, and come to find out we have a hot/neutral reverse in our junction box in the attic that is connected to the outlet. Why he didn’t catch the issue when he first installed the outlet, I have no idea. This means we’ve had an improperly wired outlet for the past half a year, and every time a device has been plugged in, the neutral has been hot! So it’s very likely that the outlet is our culprit. Considering that it was the HDMI cable that was connected to the projector that caught on fire, and the projector was connected to the outlet that was connected to the improperly wired junction box… (The toe bone’s connected to the heel bone; the heel bone’s connected to the foot bone; the foot bone’s connected to the ankle bone…). If the HDMI ports in the projector are connected to the neutral, that makes it even more likely.

So, in the end, the damages are:

Kinivo 4×2 matrix – Replaced free (under warranty)

Splitter          - $25 (works, but I didn’t like the multimeter readings, so I replaced)

PS3               – $99 RMA repair

Cable box         – Replaced free by AT&T

Projector         – $30 RMA repair (under warranty), self-paid shipping

ASUS Monitor      - Repaired free (under warranty)

New HDMI cables   – $40 (CL3-certified in-wall was $30, shorter generic cables were $10)

———————————————————————————————-

- $194 total cost

So, tomorrow I’ll head down to the UPS center and drop off all the equipment that needs to be RMA’d or repaired. All in all, it hasn’t been a fun week, and it looks to be another week or two before we’re back up and running completely. I’m just thankful no one was hurt, but holy shnikies this is an adventure I don’t want to have ever again… At least it made game night a little more interesting?