I replaced the fans with delta Delta AFC1212DE 12038 12cm 120mm DC 12V 1.6A, 4500rpm
With these, the miner restarts every 20 seconds immediately after the start.
When I set the fans to manual restarts they stop.
How to solve this, I would like to have fans at automatic speed.
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This happened to me too.
The problem is that at startup / warmup the software sets the fan speed to a very low value (1% in my case) and then it complains that the fan is missing when it sees the rpm value drop below a certain (unknown) level. My fan was doing 120 rpm with the 1% command.
I opened a support ticket and was basically told it was all my problem. That they had seen this with 3rd party fans.
I offered the solution of not checking fan rpm minimum unless the commanded speed level was above, say, 10%. This type of checking is normal for anyone that has done actual real world hardware control.
They said that they may include a "feature" sometime in the future that will allow a user to set some minimum level.