Last month, a thunderstorm did a number on me. Fried my tankless water heater control board and one of the remotes, one monitor, a bank of ports on my core switch, the ethernet port on my ADSB feeder, an active USB cable, two USB hubs, my CNC router controller, et cetera… But for this thread, the significant damage was the LMC-DIGIT-L4 controller in my (modified) CloudRay EC30 CO2 galvo. As it was connected to all the USB stuff that was fried, I just checked the power supplies and wrote it off as dead.
I was going to replace it with an identical controller, but it appears that the controller that was in it reached end-of-life and is generally unavailable. The replacement seems to be the FB/SZLI-B-LV7, which has a pair of dip switches you switch to make it work like the old DIGIT for a CO2 galvo. I ordered one from AliExpress, and it recently arrived. The four connectors (IO, galvo, laser, and USB) are all the same shape and size, so I figured it ought to be straightforward.
Well, a quick swap was successful in restoring most of the functionality. I could connect to the laser again, and I could frame, but to actually get the laser firing, there was one more thing to do. Although the laser connector is the same DB25 on both the DIGIT-LV4 and the LZ7, the pinout is very different. Thankfully, in a post last year, Issue with FBL1-B-LV7 Control board with Cloudray EC Series Neo 30W (Galvo Co2) - #17 by LTC, someone posted a link to manuals for both controllers. The LZ7 one was in Chinese, but it was easy enough to compare and then use Google Translate to verify.
My CloudRay EC30 CO2 Galvo only had two pins connected in the DB25. They were to PWM+ and a GND. I just had to desolder the wires and move them to pins labeled PWM+ and GND on the pinout of the LV7. Specifically, this change (LV4 on the left, LV7 on the right):
I soldered the wires onto the new pin locations, closed everything up, and tested it… and it didn’t work. Nuts. I was sure I had it right, so I opened it back up… and found one of the wires broke off on reassembly… and then the other wire broke off, too. Well, okay, then. I clipped some nice stranded silicone-jacketed hookup wire from my electronics bench, soldered some new wires on, and connected them (outside the DB25) to the fragile, solid-core original wires. Closed everything up again, and Bingo!
So, if anyone else ends up needing to swap controllers, just be aware that the pinout on the DB25 for the laser is not the same between the DIGIT-LV4 and the newer LV7. My, is it a relief to have my CO2 galvo back up. I guess now it’s on to the CNC router, as the thunderstorm took it out the very weekend I was going to finally load up MillMage and get some chips flying. Go figure. 