Rosa2003
asked on
Calculating Watts for laptops and scanners
I need to calculate power consumption for three devices:
- Laptop (with a Digital Camera) = 50 Watts
- Scanner Fingerprint = 35 Watts
- Scanner Signature = 35 Watts
I've read that a laptop needs 50 Watts and a standard scanner needs 35 Watts. So, I assume that I would need 120 Watts in total. Say 155 Watts, just in case.
I'd like to supply energy through a solar panel. This solar panel has to supply 155 Watts.
Could anybody tell me if I am correct in my calculations?
And could you recommend me a brand of solar panel for the devices that I need?
Thank you!
- Laptop (with a Digital Camera) = 50 Watts
- Scanner Fingerprint = 35 Watts
- Scanner Signature = 35 Watts
I've read that a laptop needs 50 Watts and a standard scanner needs 35 Watts. So, I assume that I would need 120 Watts in total. Say 155 Watts, just in case.
I'd like to supply energy through a solar panel. This solar panel has to supply 155 Watts.
Could anybody tell me if I am correct in my calculations?
And could you recommend me a brand of solar panel for the devices that I need?
Thank you!
ASKER
Thank you Rid,
Sorry for my bad english. Yes, I meant fingerprint scanner and signature scanner. I suppose that they will take same power consumption as standard scanners.
I thought that it would be enough to feed the devices with solar panels.
What would be the difference between feeding devices with DC and via inverter > AC ?
Sorry for my bad english. Yes, I meant fingerprint scanner and signature scanner. I suppose that they will take same power consumption as standard scanners.
I thought that it would be enough to feed the devices with solar panels.
What would be the difference between feeding devices with DC and via inverter > AC ?
ASKER
Do you think that using a 155-Watt UPS for my devices would be cheaper than using solar panels? I have to add the cost of using a mini-generator or a car lighter for the UPS.
I'm in a Caribbean island, so that's why I'm thinking using solar panels.
I'm in a Caribbean island, so that's why I'm thinking using solar panels.
In the first case (direct DC feed) the solar panel output voltage must match the required input voltage of the devices. May be tricky if they are not the same.
In the second case (AC feed) you need to calculate for losses in the inverter (solar panel DC to AC) and the "power bricks" (the "transformers" that change the AC back into DC to feed the laptop and scanners).
Any voltage conversion will induce losses.
My guess (a guess, mind you) is that a fingerprint scanner takes very little power as these are built into some laptops. An extra 35 W seems a bit heavy for a laptop...
/RID
In the second case (AC feed) you need to calculate for losses in the inverter (solar panel DC to AC) and the "power bricks" (the "transformers" that change the AC back into DC to feed the laptop and scanners).
Any voltage conversion will induce losses.
My guess (a guess, mind you) is that a fingerprint scanner takes very little power as these are built into some laptops. An extra 35 W seems a bit heavy for a laptop...
/RID
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I looked at a couple of laptops and thery are rated 60 - 70 W max, which probably means that they'll take something like that when running AND charging their main batteries. Depending on your funding of this setup, you may take into account that the laptops will take less power if run without the batttery inside; solar panels aren't cheap. Running without batteries in a laptop will of course have some drawbacks... a brownout will probably be pretty inconvenient.
What kind of scanners are the ones you mention - fingerprint scanner?
/RID