Is anyone still interested on how the upgrade can be done?
I've figured it out, without de-potting my board, AND keeping all safety features. (still needs more testing before I do this for someone else)
There are only 2 or 3 parts that need to be changed.
The 270V varistor is the most important, It has a marking of ZNR V10271U
The part number for this is actually ERZV10D271. It has a rating of 270V. The data sheet for this part is http://industrial.panasonic.com/www-dat ... 000CE2.pdf
It states that it is intended for 100-120V circuits.
Simply doubling the rated value seems to be working.
I wanted to swap it out for ERZV10D511, but the shop i went to didn't have the exact brand, so I used 0550NR07D (8mm instead of 10mm, rated for 550V instead of 510, green instead of black)
The other main part was the transformer, the power supply for the unit is a simple 7812 linear regulator, it CAN take DC, but you'd need at least 15V, I only have 12V AC-DC adapters, so I wired an AC adapter that works on 100-240VAC directly to the 12V output pin.
If I were to do this again, I'd use http://search.digikey.com/us/en/product ... ND/2203621
The last part is a little interesting. It has to do with those 2 diodes you can see. As we know, the unit detects if ground is present by intentionally leaking some current to the ground line. For some reason, it does this with DC, and has 1 diode from each AC input line. (hot and neutral). I tested to see if I could over-ride it and I could by simply injecting a small voltage to that resistor, but it was all unnecessary since the unit DOES NOT check/care which is live and which is neutral, but it does check if there is a complete circuit.
Initially I wanted to upgrade the diodes to 1n4004 (400V) rectifiers, (this is because standard diodes are rated in 100V increments, so they are likely only 200V) I also figured that by double the AC (with 240V) one would double the DC on the rectified side and thus double the small voltage it uses to detect ground, which may cause some problems. After I upgraded one diode, I figured, what do I need the other one for? it is only active when there is a voltage present on the neutral line, and the current goes to ground, not back into the AC circuit, so I removed the diode on the neutral line, so it will work with either neutral or L2, it is using Live or L1 to detect ground. Since L1 is only 120V, it probably wasn't required to upgrade this diode, but hey, I'm not going to fix what isn't broken.
WARNING, IF YOU ATTEMPT THIS AND SCREW SOMETHING UP, ITS YOUR OWN DAMN FAULT. YOU WILL BLOW UP LIKE IN DISTRICT 9, (don't ask me how I know)