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Title: Harmonics in electrical system from mining off genset? Post by: VentMine on March 06, 2018, 10:40:57 PM Hey guys,
Curious I was talking to a genset vendor today and he mentioned running "server-like" equipment (Antminers) off of a genset may potentially have issues with harmonics and require harmonic conditioning to protect the alternator. Should I be concerned about this? Title: Re: Harmonics in electrical system from mining off genset? Post by: HagssFIN on March 06, 2018, 10:46:41 PM There are always harmonics present when using switched-mode power supplies.
If the harmonics start to be an issue, you can reduce the impact by adding a harmonics filter system in to your electrical system. Title: Re: Harmonics in electrical system from mining off genset? Post by: NotFuzzyWarm on March 07, 2018, 04:12:47 PM Yes harmonics issues are possible if using cheap PSU's. However, most today have PFC - Power Factor Control - that mitigate the problem. Most will advertise if they have PFC and give a Power Factor rating. A perfect resistive load gives a PF of 1.0 and most PSU's will be around 0.85 to 0.9 or better.
Title: Re: Harmonics in electrical system from mining off genset? Post by: VentMine on March 07, 2018, 05:26:04 PM Yes harmonics issues are possible if using cheap PSU's. However, most today have PFC - Power Factor Control - that mitigate the problem. Most will advertise if they have PFC and give a Power Factor rating. A perfect resistive load gives a PF of 1.0 and most PSU's will be around 0.85 to 0.9 Ahh k. Thanks gents. So I take it the Bitmain supplied PSU's have this as I recall their powerfactor is 0.95 Title: Re: Harmonics in electrical system from mining off genset? Post by: HagssFIN on March 07, 2018, 05:39:07 PM Yes harmonics issues are possible if using cheap PSU's. However, most today have PFC - Power Factor Control - that mitigate the problem. Most will advertise if they have PFC and give a Power Factor rating. A perfect resistive load gives a PF of 1.0 and most PSU's will be around 0.85 to 0.9 ^ This. More usual case to end up in problems with harmonics is that if you have a lot of load consisting frequency converter controlled electrical motors for example. So if you use good PSUs with PFC inside, harmonics shouldn't be an issue. Title: Re: Harmonics in electrical system from mining off genset? Post by: HoleShot on March 08, 2018, 03:26:06 AM I usually measure .97 PF on APW++ PSUs from Bitmain.
You can avoid almost all harmonics issues by avoiding non-resistive loads that use the neutral. So, run all your power supplies, pumps and fans on 240V, but the coffee pot is fine on 120V. Title: Re: Harmonics in electrical system from mining off genset? Post by: VentMine on March 08, 2018, 06:34:14 PM I usually measure .97 PF on APW++ PSUs from Bitmain. You can avoid almost all harmonics issues by avoiding non-resistive loads that use the neutral. So, run all your power supplies, pumps and fans on 240V, but the coffee pot is fine on 120V. The gen outputs 3-phase, so I have it configured to 230V L-L, 133 L-N. The 240/120 is single phase I believe? Thanks for the responses guys, I didn't think I needed to worry about filtering but a recent conversation with a genset supplier spooked me. Title: Re: Harmonics in electrical system from mining off genset? Post by: HoleShot on March 09, 2018, 07:04:22 PM Yes, the 230V/133V is your 3-phase output.
You should connect your miners like this. A,B legs to miner 1 B,C legs to miner 2 C,A legs to miner 3 Then continue to rotate like this until maximum power is reached. I would not use the neutral. I would not use the single phase output. |