It’s been a while so I thought I’d keep everyone up to date. The issue of surge protection has recently come to my attention a couple of time. If you’re off grid (or even on grid in a rural area) and not using any surge protection, please do. The ballasts we use are fairly robust but if the internal fuse blows in them they are as useful as a brick. Thankfully this doesn’t happen often but your warranty doesn’t cover the controller in this instance, you’re expected to have suitable protection.
It’s fairly cheap, just go down your local builder merchant or DIY store and there should be someone there who can help you track something down.