random Classic time resets

[kitestrings]

dgd,

What's not real clear is the rectifier.  It's basically dual full-wave stud mount diode bridge rectifiers.  There are six diodes in the front sinks, and six in the ends.  The front panels hinge to the sides to access the 'inards'.  I guess the important thing is that each Classic has an isolated input.  The rectifier box also houses the breakers (50A, 300V), the dump and hi-limit relays, the Omron relay, and a tachometer circuit board which indicates rotor rpm on the front gauge (volt meter).

boB,

It's mostly been the primary (I'll call Classic A 'primary', Classic B 'secondary'), typically about the point where Classic A is near current limit and Classic B is just starting to see load.  I think I've seen it at least once on Classic B.  I'm not sure how to get it to you, but I've sent a video of it to Roy & Ryan.  Perhaps they could forward?

What happens if you disconnect the secondary Classic while you are getting the OCPs and Resting ?

I haven't tried this, or vice versa (disconnecting A), but we can when we get it down.

I wonder if your Clipper just Clips a bunch (because the system is over-powered) and no OCPs or
Resting happens then ?

I've played with the "clip" set-point quite as bit, trying to see if it might help to be clearly above -or below the point where B comes in.  At lower voltage set-points the load bank will get pulsed without any issues.  Seems to always be at higher loading on A.

Initially we thought it might be when the diversion load came in, but it happens with that disabled.  During good solar weather (like now) we divert about 45A (48VDC) to the water heater using Aux2 waste-not, and there are no problems.  Of course there's no wind complicating things, and the Vin from the PV is comparatively very flat and invisible to the Classics.

This all seemed somehow more important until I read your recent post.  Thoughts (of many here) are with you.

[kitestrings]

Hi.  Just a quick update, we're pulling down the turbine this Saturday (postponed from July), so we should have the ability to motor-up the alternator for testing, determining LTR codes, etc.

One detail I wanted to ask folks here.  Dgd had cautioned us earlier about the "protection diode" that we are using - should it fail.  Briefly, we have Aux2 output of one controller connected to our 3-ph load bank (home-made clipper) via SS relay.  This signal is 12V.  We also have an Omron voltage sensitive relay connected to this relay, but it is a 24V output.  The diode, Dgd pointed out is the only thing separating the two, different outputs.  I just wondered if any one might suggest a better protection scheme?  I've seen some small, low-power switch-mode DC/DC converters...there are DIN rail power supplies (a bit pricier)...or maybe just a linear voltage regulator?  I'd like to keep it simple.

Thanks for any ides.  ~ks

[dgd]

Ks,
sorry didn't mean to worry you about the diode. Usually when they fail they go open circuit, however, I suppose there could be a closed failure.
Rather than use a voltage level shfiter I would simply put another diode in series with the first. The extra small voltage reduction is probably insignificant in switching the SSR.
dgd

[kitestrings]

Thanks Dgd, that sounds simple enough.  Under normal conditions the Aux2 will pulse the load bank to keep things safe, and the Omron would only operate as a fail-safe, but I want to plan for the worst case.  I have the Omron fused also.

So both would have to fail (closed for there to be a problem), correct?