| General > General Technical Chat |
| Watt the fμck? |
| << < (12/19) > >> |
| coppice:
--- Quote from: james_s on September 29, 2022, 07:58:40 pm --- --- Quote from: coppice on September 29, 2022, 07:02:04 pm ---The problem with standby power is little settings deep in configuration menus can massively affect it. The only way you can figure out the real effect of each setting is using a power meter, which few people have access to. --- End quote --- Anybody has access to a power meter if they want one, those Kill-A-Watt and similar devices are inexpensive and have been available for at least a decade. --- End quote --- They aren't great for measuring for measuring standby power, as they don't measure well at the one or two watt level. If you are going to get one get an actual kill-a-watt, as most of the clones are pretty awful across the whole power range. Some don't even measure active power - they give a rough apparent power reading. A real kill-a-watt will do well at telling you when you have a really gross standby consumption, like the 50W TV I referred to. I guess it will work fairly well for comparative measurements, too. Its not great, though. |
| AndyBeez:
Power scheduling network hardware not only saves money, the planet and the MTBF, but it also keeps hackers from dialing into the network when you're in bed and they are eating their midday bun cha. PoE scheduling is good practice. But don't turn off the CCTV or the IP recorder! + I once used a device that powered down my printer and monitor when the computer switched off. It was called an eco-plug. You may have been sent one or similar by your energy supplier. Piece of unreliable junk that received a premature teardown for parts. I think I just kept the LED. In a domestic setting, there is a ton of stuff that's always on and turning the meter. Not just the phone chargers, fridges, aircon and heating system, but other 'subliminal' stuff like cookers, hobs, ovens, extractor fans and dish washers. Maybe even the solar panel inverter is secretly sipping the off hour watts? There is only so much that can be turned off. One saving you can make.... |
| AVGresponding:
--- Quote from: Neper on September 29, 2022, 06:38:34 pm --- --- Quote from: AVGresponding on September 29, 2022, 04:40:25 pm ---It doesn't mention the Wh rating of the battery, but at £160 for a 2kVA unit with battery installed, I'm guessing it's not much, one of the 12V 40Ah batteries they show on the same page maybe? --- End quote --- Not even that. Two batteries of 12 V 9 Ah each. --- End quote --- :palm: 9Ah is a non-standard size, I wonder if it's really a 7Ah that they massaged the discharge rate on, to get a more favourable capacity? Either way, at the rated load, you'll get less than 5 minutes of inverter time to do a controlled shutdown (assuming you're protecting a PC). Realistically a PC running at say 200W, you'll get probably thirty minutes or so depending on the low battery voltage shutoff settings. The batteries aren't going to be very happy in any case though. |
| timenutgoblin:
--- Quote from: paulca on September 28, 2022, 05:50:15 pm ---Forget the momentary devices like kettles, coffee machines, etc. Track the high power items. (Why not the obvious kitchen? Because if you need, you need. They are momentary, choice items.) kwh = £0.39p UK as of 1st Oct. It starts to matter. --- End quote --- If your kettle is rated at 2200W (2.2kW) and is switched on for 90 seconds at a time, 5 times day, then at £0.39p per kWh it will cost you £9 - £10 per quarter-year (90 days or 3 months). Do you use a laser printer? My laser printer is rated at 4.3A 240V and uses nearly 1000W (1kW) while printing. Fortunately, I rarely use it. |
| james_s:
--- Quote from: AVGresponding on September 30, 2022, 05:38:42 am ---9Ah is a non-standard size, I wonder if it's really a 7Ah that they massaged the discharge rate on, to get a more favourable capacity? Either way, at the rated load, you'll get less than 5 minutes of inverter time to do a controlled shutdown (assuming you're protecting a PC). Realistically a PC running at say 200W, you'll get probably thirty minutes or so depending on the low battery voltage shutoff settings. The batteries aren't going to be very happy in any case though.[/color][/size][/b] --- End quote --- 9Ah is the most common size of SLA battery I've ever encountered, they're the same external dimensions as the 7Ah type. Of course in UPS duty you don't get anywhere near that rating, which is for a far slower discharge. |
| Navigation |
| Message Index |
| Next page |
| Previous page |