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1307 Review
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Review on πŸ”Œ BrovSS: 10 Port USB 2.0 Powered Hub - High Capacity USB Extension Splitter with 12V 5A 60W Power Adapter. Seamlessly Connect up to 10 Electronics and USB Peripherals. (Black) by Brock Chisholm

Revainrating 3 out of 5

Waste of energy and money

Like many others, I bought this to run multiple USB miners and fans to cool them. Maybe charge my devices with it and get rid of a lot of USB chargers with different ratings. So 60W = 12V 5A. No "real" thing behaves ideally, and there are always losses, but. Well, to simplify the math, switching, since power is a multiplied quantity. So let's say 5V at 12A. Ten ports. 10 x 600 mA = 6 A. Total. Where does the extra 90% of the energy go? The solid construction and the presence of mounting brackets are positive. If I didn't return the thing I'd be tempted to look inside and guess, but c'est la vie. I even wanted to keep it as a high-end hub, but lossless USB 2.0. Consumes 100-240 VAC [peak] at 50/60 Hz duty cycle, 1.6 A max and nominal 120 VAC [peak] - AC power consumption: - V = I/R - V[peak] = 120 VAC - V[rms] = sqrt(2) x V[peak] - I[line] = 1.6 A - P[line] = V[rms] x I[line] - P[line] = 169.7 W - P[in] = V[rms] * I - P[in] = 169.8V RMS - V[hub] = 12VDC - I[hub] = 5A - P[hub] = 60W or so. Enough to power a very bright incandescent bulb. Energy that is simply wasted through entropy, parasitic capacitances, ohmic heating, etc. 35% efficiency. Now let's move on to the hub itself. 10 ports each provide 5VDC at 600mA. Ideally, that would mean that we actually only need 30V DC, but the ideal isn't a reality. But for some reason I want to lose half. Ouch. Final efficiency: 17.67% (assuming all ports are occupied and drawing 600mA max). Average US Electricity Price as of 6/2019: $0.139. Electricity consumption for 1 day: 0.031 kWh. Start-up cost 1st day: $0.10379 Week: $0.72654 30 days (your utility bill every month even if you left this unit idle and on): $3.12 3.1137588530905857546496061654136 To be exact I have used extra precision all along to spare you just the gory details. And for a year (365.25 days) it's $37.91. It may seem that this is not so much. But you're working with cryptocurrency mining on devices that might be VERY generous at 20-25 Gh/s. If they're getting 3A, not 600mA. You can have up to 10, but you'll probably want a USB fan connected to 1-2 ports for cooling - ASIC miners get hot very quickly. But, let's say, cooling doesn't matter. 10 x 25GHz/s. Mining doesn't even come close to being profitable until you're in the Terahash region, even without electricity - you have to buy hardware and set it up, or of course someone will do it for you. Electricity is bottom line in terms of profitability, so you need to steal every joule you can. :-PI already returns mine. 2 stars, structure and design were excellent. That's easy. ill suited for what it is billed for. I don't want to say "false advertising" because theoretically you could install this and lose some money, but it's definitely misleading. If it was cheaper and the description didn't explicitly say "For mining", I would never have bought it. 5A 60W adapter for mining? 600mA? The ASIC stick I ordered requires 3A to run above 100MHz. Want to run a Raspberry Pi? Similar requirements.

Pros
  • Confident
Cons
  • Weight