Are these equivalent?
- Thread starter firerock
- Start date
Travis L. Stevens
Active member
No. What is the fan rated for? 6 volts or 12 volts?
firerock
New member
12v, this is what I am trying to do, simply replicate Hahn's mod for the Tek down toward the bottom half of the page.
http://www.reefcentral.com/forums/showthread.php?s=&threadid=1013083&perpage=25&pagenumber=8
This is the specs for the fan:
http://www.coolermaster.com/index.php?LT=english&Language_s=2&url_place=product&p_serial=STF-B01-E1
Thanks for your help.
http://www.reefcentral.com/forums/showthread.php?s=&threadid=1013083&perpage=25&pagenumber=8
This is the specs for the fan:
http://www.coolermaster.com/index.php?LT=english&Language_s=2&url_place=product&p_serial=STF-B01-E1
Thanks for your help.
Bergovoy
Moved On
not sure I understand.
You have a 12 volt power supply and you wnat to find out if it will work for a fan that requires 12 volts??
I dont see a problem
Why would you consider a 6 volt power supply?
If you did, the fan would run slower, the fan would draw more current,t he power supply and fan would run a bit hotter.
(and btw: I am lookoing for a web designer, pm if you are interested in setting up a web page that is linked to my aqua Controller)
Bill
You have a 12 volt power supply and you wnat to find out if it will work for a fan that requires 12 volts??
I dont see a problem
Why would you consider a 6 volt power supply?
If you did, the fan would run slower, the fan would draw more current,t he power supply and fan would run a bit hotter.
(and btw: I am lookoing for a web designer, pm if you are interested in setting up a web page that is linked to my aqua Controller)
Bill
firerock
New member
I am trying to do the mod that Hahn had done with his Tek.
With his par meter, he hooked up the fan with an AC adapter at 3V, 6V, 9V, and 12V, and the ultimate output was achieved with 6VDC 1000mA. Currently, I have AC adapter at 12VDC 500mA, 9VDC 300mA, and 6VDC 200mA. Which one of these will give me the output equivalent to 6VDC 1000mA?
According to CoolerMaster website, the fan I am using has the following specs.
Voltage DC12V
Start Voltage 5V
Current 0.24amp
Speed (4speeds) OFF 0 r.p.m
LOW 1400 r.p.m ( 6.5 V )
MIDDLE 1800 r.p.m ( 8.5 V )
HIGH 2500 r.p.m ( 12 V )
Thanks for the help. :rollface:
With his par meter, he hooked up the fan with an AC adapter at 3V, 6V, 9V, and 12V, and the ultimate output was achieved with 6VDC 1000mA. Currently, I have AC adapter at 12VDC 500mA, 9VDC 300mA, and 6VDC 200mA. Which one of these will give me the output equivalent to 6VDC 1000mA?
According to CoolerMaster website, the fan I am using has the following specs.
Voltage DC12V
Start Voltage 5V
Current 0.24amp
Speed (4speeds) OFF 0 r.p.m
LOW 1400 r.p.m ( 6.5 V )
MIDDLE 1800 r.p.m ( 8.5 V )
HIGH 2500 r.p.m ( 12 V )
Thanks for the help. :rollface:
Last edited:
firerock
New member
I actually saw your post, and thought it was replied with tons of great info. If you want something simple, then follow the suggestions given in by fellow "geek" reefers will be sufficient enough for your application needs as described in your thread. Also, it seems like you have received many referrals already. It is nice to find so much tech help in a reef forum.
bromion
Active member
I see... the fan has variable speeds based on voltage. In that case, the 6V 200mA will probably work, as the fan shouldn't draw more than 240mA (according to the numbers listed) and will likely draw less at lower RPM.
I don't see why the fan speed would affect the lighting output significantly. If anything, I would think higher speed would cool the lamps better, giving better performance. Maybe the design of the enclosure actually optimizes the flow at lower fan speeds.
rscott76
Member
From what i have read/heard DE bulbs in particular have a higher temp "sweet spot" where performance and longevity of the bulb are optimized...overcooling actually decreases the life of the bulb. DE bulbs have a higher operating temperature so that might explain why the optimal PAR result was when the fan was running a little cooler. The same pertains to the T5 setups with their "optimal" temperatures. The voltage to run the fan at would be directly related to the number of bulbs, the fixture size and the ambient air temperature though so without an identical setup, your optimal cooling speed may be different.
as far as the adapter goes....assuming high school AP physics still holds water in this case and that V=IR holds true, and also that the resistance doesnt change, the current draw at 6.5V should be a little more than half of the current draw at 12V so you should be ok with the 200mA adapter. But then again i would play it safe and give yourself a little buffer because you know how the laws of physics are always subservient to the laws of murphy (a dead fan is just not cool, you know :bum: ) I had alot of good experience with a variable voltage adapter you can get at places like walmart or the local drugstore. Just cut the other end off and wire your fan circuit in directly. That way you can adjust upward or downward depending on your own situation.
as far as the adapter goes....assuming high school AP physics still holds water in this case and that V=IR holds true, and also that the resistance doesnt change, the current draw at 6.5V should be a little more than half of the current draw at 12V so you should be ok with the 200mA adapter. But then again i would play it safe and give yourself a little buffer because you know how the laws of physics are always subservient to the laws of murphy (a dead fan is just not cool, you know :bum: ) I had alot of good experience with a variable voltage adapter you can get at places like walmart or the local drugstore. Just cut the other end off and wire your fan circuit in directly. That way you can adjust upward or downward depending on your own situation.
BONDQ
Premium Member
<a href=showthread.php?s=&postid=9326009#post9326009 target=_blank>Originally posted</a> by rscott76
does the resistivity of the motor change then? I assumed that the motors properties stayed constant and that the current draw change was a function of the voltage supplied. I mean, im by no means an electrical engineer, but i did score a 5 on the AP test
Voltage and current are entirely independant calculations.
Voltage is a measurement of difference in potential. (Think of this like water pressure) We generally measure water by PSI "pounds per square inch". The Voltage is the electrical pressure.
Current is basically a measurement of the amount of flow of electricity (like gallons per minute would be for a pump).
The fan needs the same "flow" of power sent to it at all times, but the change in potential (voltage) causes it to change in speed.
The motor is not changing, but the potential of the circuit defines it's operation.
rscott76
Member
Ohm's Law?
V=IR?
am i off my rocker with this...i mean the whole flow model works right but youre leaving out the fact that the resistor can be analogous to a valve placed on the circuit. According to ohm's law voltage and current are directly proportional. Im not trying to start an argument with you here but if you increase the pressure and the resistance of the piping and valve stay constant, doesnt the velocity of the water increase until the inner turbulent forces are equal to the pressure forces?
The fan can be looked at as a simple resistor as a part of a DC circuit in this case can it not? again im not trying to pick a fight with you...im sure youre well qualified to answer the question but I just dont see an increase in electric potential in a circuit with an unchanging resistor causing no change in the current.
maybe they just didnt teach enough physics in the biochemistry program?
V=IR?
am i off my rocker with this...i mean the whole flow model works right but youre leaving out the fact that the resistor can be analogous to a valve placed on the circuit. According to ohm's law voltage and current are directly proportional. Im not trying to start an argument with you here but if you increase the pressure and the resistance of the piping and valve stay constant, doesnt the velocity of the water increase until the inner turbulent forces are equal to the pressure forces?
The fan can be looked at as a simple resistor as a part of a DC circuit in this case can it not? again im not trying to pick a fight with you...im sure youre well qualified to answer the question but I just dont see an increase in electric potential in a circuit with an unchanging resistor causing no change in the current.
maybe they just didnt teach enough physics in the biochemistry program?
BONDQ
Premium Member
The topic of this thread was whether or not each AC adapter was giving the same values. The answer to that question is "No".
I was giving support to that answer.
In a DC motor, you are correct, current does fluctuate according to forces implied by magnets internally. This directly affects the electricial resistance as the brushes pass the magnets.
But, I don't believe Firerock's question was surrounding the circuit itself, but was focused more on input voltage and current as supplied by the power supply itself.
A 6VDC 1,000mA power supply and a 12VDC 500mA power supply will not give the same results here. That's all I was saying.
I was giving support to that answer.
In a DC motor, you are correct, current does fluctuate according to forces implied by magnets internally. This directly affects the electricial resistance as the brushes pass the magnets.
But, I don't believe Firerock's question was surrounding the circuit itself, but was focused more on input voltage and current as supplied by the power supply itself.
A 6VDC 1,000mA power supply and a 12VDC 500mA power supply will not give the same results here. That's all I was saying.
