Thats NOT a Suntie XR-UPG

It should read Rev 5.0 , Enhanced with GP Technology if its an upgraded inverter

Time to call Xantrex !

Version 3.2 is the old XR code

That's it -- you're right.

In June 2003, when I sent the ST-2500 in for refurbishment, I figured that Xantrex would bring it up to date.

They didn't. Instead, they moved it from an ST-2500 to an STXR-2500.

Xantrex wants $400 more to go from STXR-2500 to an STXR-2500 UPG.

If the UPG improved the efficiency by 20 percent, a $400 upgrade would not pay for itself within 10 years. Probably not within 20 years.

*sigh*

Him ,

you spend 110 bucks on an opto isolator which gives you zero percent return and use a P4 PC power pig to monitor the inverter (whats the P4 cost) ...

at a dime a kWh , you need to generate an additional 4,000 kWh over the lifetime of the inverter. My system does about 4,000 kWh year so in 5 years it pays for itself

You should consider a used cheap laptop
like this cheap ebay laptop or use a low power motherboard like mini-itx motherboard. The solar-guppy server is a mini-itx , draw 11 watts running disks test (laptop drive). I used a pair of the compaq lte to monitor my arrays for awhile , go cheap low power computers

Just get the upgrade , trust me , you'll be VERY happy with the increased performace