Electronics question

[pete_c]

You can crack it open and have a look to see which kind it uses.
 
Interesting as I did that yesterday.  Here are pictures.  Found a small plastic case.  Have a bunch of these collected over the last few years originally purchased from all electronics dot com.  (old ones are regular mini USB and new ones are micro USB).
 

 
Going to use this one now for the GPS modded with PPS 5VDC power (NTP server clock) for PFSense firewall. 
 
Putting this inside of the Leviton can and currently using a small GPS antenna hitting up to 12 GPS satellites from a nearby window.
 

 
Here is what the TP-Link looks like in the OP2 panel.  Looks bigger than it is as I fit the TP-Link between the zone expanders and the side wall of the OP2 can.
 

 
@Cestor...you got me doing this with your endeavor today...are you doing Tiger's project?

 

[dementeddigital]

I don't see a power supply in the router, but I would assume that it only takes 5V in from an external source.  I was thinking that you might open the automotive power supply to see if that one has a switching regulator.  I bet that it does, and you're probably OK with using it.  POE works, too.
 
What is Tiger's project?  I've got a Mega sitting around waiting for a project.  Maybe I'll do this one with both of you!

 

[cestor]

No - the arduino controls my somfy blinds and I was making it a bit more robust. What is Tiger's project? 

 

[pete_c]

Serial connectivity to the OP2 panel using an Arduino...
 
See here...

Arduino and Omni PRO II via serial - first working code.

 

[dementeddigital]

Serial connectivity to the OP2 panel using an Arduino...
 
See here...
Arduino and Omni PRO II via serial - first working code.

 
That looks like a fun project.  I need to make a serial interface between the Omni for both my stereo receiver and HDMI switcher.  I was just going to trigger them with ASCII strings sent to an Arduino on a spare serial port, but this looks more elegant.

 

[pete_c]

I enjoy tinkering...
 
back to OP
 
So here are my questions:
 
1. does this seem like a likely cause? 
 
As mentioned above yes maybe.
 
2. Is it bad practice to use the same supply connection for multiple +12v  and GND
 
Personally I am paranoid about power / ground having seen a few peers hiccups with DIY installations of the OmniPro 2 panel. 
 
That said historically always used autonomous PS's until I started to tinker with the micro router installation and there too it was not a direct connect to the power block (sort of).
 
3. Is there a solution that doesn't involve a terminal block that is 50 wide and takes up a huge amount of space...
 
There are many solutions today with the miniaturization of this stuff especially with the Arduino / RPi stuff for your project. 
 
As always mentioned on the forum here is that the panel is a life safety device and typically from the vendor you have UL approval of the stuff you install inside of the panel. 
 
There are more comments Cestor from folks reading your stuff here. 

 

[cestor]

I have now replaced the power to the terminal block with a 2a mains adaptor and ordered a new Arduino...here's hoping! 

 

[pete_c]

So then when you are referring to "the terminal block" it is an autonmous source for the Arduino power and connected devices?
 
The OP2 can is small and personally here have had issues fitting accessories inside of it. 
 
Tell us a bit about the base OP2 and additional boards you have inside of it.
 
IE: Here have two zone expanders (16 zones X 2 plus base 16 zones).  Then I have tiny smoke and CO detector boards for 4 wire devices tacked on to the top and side adjacent to the main board.  Many folks have added the email board to the mix.  I am also using all of the serial ports plus X10 port on the panel.  (IE: UPB, X10, ZWave, Zigbee plus Russound and software on a serial port here - many wires)
 
So what kind of terminal block are you using? 
 
I would start maybe by tinkering outside and autonomously first with the Arduino and maybe just running the serial cable to the inside of your OP2 panel.  One gotcha inside of your panel and you can trash it.  I did this to a new panel powering it up using the wrong terminals.  I saw a flash and smoke.  HAI did replace the new panel.  It was only a week old at the time.  After a bit of time redid the lighting over the panel such that I could see the inside better.
 
Here recently installed one of these (purchased two of them).  These are available at All Electronics.
 
It is one source 12VDC negative and postive to 6 pairs of 12VDC devices plus it has a little LED lamp indicating power.
 
These are tiny even though the picture makes it look big.
 

 

[cestor]

Yes, it's an autonomous power source for the various zone detectors, as well as the Arduino. I like the block that you have posted above.

 

[pete_c]

The terminal block above is at All Electronics for $5.75 USD.
 
UNIVERSAL POWER / DATA BUS TERMINAL
 
Over the years had just twisted power leads (using little wire caps) and recently decided to neaten up the wiring a bit with the above mentioned terminals.