DC/DC converter education . . where?
OK - the vast majority of electronic equip I have are all battery-power based: laptop, cell phone, bluetooth, tablet, cat-tracker, and portable battery pack. The most power-hungry being the laptop. A...
Forum Discussion
2oldman writes “When dry camping, my inverter is never off, so the 0.5a (in my case it's higher) is a 'sunk cost' to me. I turn off unneeded devices at night, but never the whole system. I have 640ah of batteries and 835w of solar. hondochica, while maybe not that endowed, sounds like he has plenty o' power too.
If you want or need to conserve, then yes, by all means turn your inverter off when you can. But on larger systems, where the inverter is never off, these "inefficiencies" are a very small part of the overall energy picture.
I don't know what hondochica's 'great' battery bank exactly is, but if it's large and easily rechared, he may too conclude it's not worth it. Is it wasteful? Yeah. Is it "incredibly wasteful"? No.”
Greenrvgreen writes “I agree with Oldman. While dc/ac/dc could cetainly acrue 30% loss, the amount of power lost is tiny. Much greater power draw would be a cheap "universal" charger that shorts out and fries your $2,000 laptop.
Power bricks are a major profit center for laptop mfrs, and they do all they can to ensure that aftermarket parts won't work right. The fact is that the OEM power brick is a consumable/sacrificial item that helps protect your expensive computer from power surges, spikes, MSW, zombies, etc."
While I certainly “agree” that “sometimes” it may not be worth it to eliminate as much loss as possible, I DO clearly understand the position of folks who DO want to eliminate unneeded conversion losses.
In the case of a cellphone charger, 5V at 2.4A is 12W, say the inverter has a .5A no load draw, that is 6W.
That 6W no load draw does not “go away” when a 120V load is applied.. Nope, that 6W draw is ADDED as a LOSS..
In the case of a cellphone charger that becomes 18W of power (provided no other 120V “load” is attached)..
As a side note, do you not own a 12V to USB 5V charger so you can charge your cellphone while driving?
I DO, makes it simple to be able to plug a cellphone right into a cig/power port on my vehicle while driving.
Not EVERYONE keeps an inverter turned on 24/7 like YOU might..
In my case, I switched to a home fridge, even in my case, my inverter does NOT run 24/7..
No, instead I bought an inverter which can sense if there is a 120V load.. When no 120V load is present the inverter SHUTS DOWN the 120V output stage and goes to sleep.. The sleep mode uses MICRO AMPS instead of the 1A no load draw it would have if I didn’t use the load sense feature.
This SAVES me a considerable amount of battery capacity! About 16 Ahr PER DAY (fridge on 20 minutes and off 40 minutes per hr).. While YOU may scoff at that, to me that IS considerable when considering I have 105 Ahr (half or 50% of 210 Ahr) to work with. 16 Ahr is about 15% of my usable capacity that I AM “saving”.. That is at least 20%-25% LESS generator recharge time when you take into account inefficiencies in the recharge cycle.
This allows me to only need ONE PAIR of 6V GC batts and still use lights, water pump, TV, computer, furnace and STILL have enough leftover capacity to only require recharging ONCE every 24 hrs.. And having only ONE pair of GC batts I save costs in battery replacements AND how long a generator would need to be run to bring the battery back up to near full charge..
The more you waste means you have to have more battery and more battery means it takes longer to recharge, YOU must have more money to “burn” than me..
CONSERVATION is “key” to boondocking, it is far cheaper to CONSERVE energy when off the grid..
"Homemade" electricity whether it is a generator OR solar is extremely expensive when compared to commercial shore power.. I would be hard pressed to be able to "compete" price wise to commercial power.. My commercial power rate is $.07 per Kwhr.. Running a generator is easily $.70 per Kwhr not including maintenance/repair/replacement of a generator..
I have no solar either.. Considered it, but just don’t boondock enough to justify the costs at this time..
Greenrvgreen, as far as those “cheap” no name power supplies burning up PCs, that is baloney.
You DO realize the manufacturer of your PC DOES NOT “manufacture” the power supplies that they include with the laptops? Pretty fair chance the power supply that came with your laptop is no better and in some cases WORSE “quality” than the “aftermarket” versions..
I HAVE been building and repairing PCs for nearly 30 yrs, never heard of a aftermarket power supply burning up a system board.. In fact I typically REPLACE the OEM internal power supplies when possible with BETTER quality and higher wattage power supplies.. Makes for a much more stable longer lasting PC, in fact my PCs outlive the average user by a long ways. I STILL have a “P4” running XP and it gets used daily and is on about 6 hrs a day at home..
The OEMs tend to buy the CHEAPEST things they can get their hands on, it is not always the “best quality” to start with.
If you want or need to conserve, then yes, by all means turn your inverter off when you can. But on larger systems, where the inverter is never off, these "inefficiencies" are a very small part of the overall energy picture.
I don't know what hondochica's 'great' battery bank exactly is, but if it's large and easily rechared, he may too conclude it's not worth it. Is it wasteful? Yeah. Is it "incredibly wasteful"? No.”
Greenrvgreen writes “I agree with Oldman. While dc/ac/dc could cetainly acrue 30% loss, the amount of power lost is tiny. Much greater power draw would be a cheap "universal" charger that shorts out and fries your $2,000 laptop.
Power bricks are a major profit center for laptop mfrs, and they do all they can to ensure that aftermarket parts won't work right. The fact is that the OEM power brick is a consumable/sacrificial item that helps protect your expensive computer from power surges, spikes, MSW, zombies, etc."
While I certainly “agree” that “sometimes” it may not be worth it to eliminate as much loss as possible, I DO clearly understand the position of folks who DO want to eliminate unneeded conversion losses.
In the case of a cellphone charger, 5V at 2.4A is 12W, say the inverter has a .5A no load draw, that is 6W.
That 6W no load draw does not “go away” when a 120V load is applied.. Nope, that 6W draw is ADDED as a LOSS..
In the case of a cellphone charger that becomes 18W of power (provided no other 120V “load” is attached)..
As a side note, do you not own a 12V to USB 5V charger so you can charge your cellphone while driving?
I DO, makes it simple to be able to plug a cellphone right into a cig/power port on my vehicle while driving.
Not EVERYONE keeps an inverter turned on 24/7 like YOU might..
In my case, I switched to a home fridge, even in my case, my inverter does NOT run 24/7..
No, instead I bought an inverter which can sense if there is a 120V load.. When no 120V load is present the inverter SHUTS DOWN the 120V output stage and goes to sleep.. The sleep mode uses MICRO AMPS instead of the 1A no load draw it would have if I didn’t use the load sense feature.
This SAVES me a considerable amount of battery capacity! About 16 Ahr PER DAY (fridge on 20 minutes and off 40 minutes per hr).. While YOU may scoff at that, to me that IS considerable when considering I have 105 Ahr (half or 50% of 210 Ahr) to work with. 16 Ahr is about 15% of my usable capacity that I AM “saving”.. That is at least 20%-25% LESS generator recharge time when you take into account inefficiencies in the recharge cycle.
This allows me to only need ONE PAIR of 6V GC batts and still use lights, water pump, TV, computer, furnace and STILL have enough leftover capacity to only require recharging ONCE every 24 hrs.. And having only ONE pair of GC batts I save costs in battery replacements AND how long a generator would need to be run to bring the battery back up to near full charge..
The more you waste means you have to have more battery and more battery means it takes longer to recharge, YOU must have more money to “burn” than me..
CONSERVATION is “key” to boondocking, it is far cheaper to CONSERVE energy when off the grid..
"Homemade" electricity whether it is a generator OR solar is extremely expensive when compared to commercial shore power.. I would be hard pressed to be able to "compete" price wise to commercial power.. My commercial power rate is $.07 per Kwhr.. Running a generator is easily $.70 per Kwhr not including maintenance/repair/replacement of a generator..
I have no solar either.. Considered it, but just don’t boondock enough to justify the costs at this time..
Greenrvgreen, as far as those “cheap” no name power supplies burning up PCs, that is baloney.
You DO realize the manufacturer of your PC DOES NOT “manufacture” the power supplies that they include with the laptops? Pretty fair chance the power supply that came with your laptop is no better and in some cases WORSE “quality” than the “aftermarket” versions..
I HAVE been building and repairing PCs for nearly 30 yrs, never heard of a aftermarket power supply burning up a system board.. In fact I typically REPLACE the OEM internal power supplies when possible with BETTER quality and higher wattage power supplies.. Makes for a much more stable longer lasting PC, in fact my PCs outlive the average user by a long ways. I STILL have a “P4” running XP and it gets used daily and is on about 6 hrs a day at home..
The OEMs tend to buy the CHEAPEST things they can get their hands on, it is not always the “best quality” to start with.
