Had the original 65A alternator on my Beta 43 die on me last week, so rather than just replacing like-for-like I thought it was a good opportunity to upsize. Ended up fitting a Iskra 120A unit with an external Wakespeed WS500 regulator. Cost me about £380 all in for the alternator plus another £280 for the regulator, which felt like a big chunk of change but I've been wanting proper adaptive charging for my 400Ah lithium bank for ages.
First impressions after a few days of cruising are genuinely impressive. Running at around 1,500 rpm I'm pulling a consistent 90–95A into the batteries during bulk phase, which is miles better than the 40-odd amps the old unit was managing. The WS500 is talking to my Victron Cerbo via CAN bus and the whole setup feels properly integrated. Belt tension was a faff to get right — went through two belts before I stopped overthinking it and just followed the deflection spec properly.
What I'm unsure about is heat management on longer summer cruising days. The alternator casing is getting noticeably warm after a couple of hours — not burn-your-hand hot, but warm enough that I'm wondering whether I should be pointing a small fan at it or fitting a temperature probe. Anyone else running a high-output alternator in a tight engine bay and had issues with sustained heat? Is the WS500's built-in temp limiting enough to protect it, or have people found it needs a bit of help?
