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Mirror-rear fan and dew controller

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#1 Piero DP

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Posted 28 February 2020 - 07:58 AM

I am rather ignorant on this topic, so apologise if the question is rather stupid.

 

I have this fan: https://www.arctic.a...ctic-f8-tc.html installed on the back of my dobson primary mirror. From the specs I can see that it can operate at 12V, 7V, and 5V, reducing the RPM of the fan.

 

If this fan is attached to a dew controller (e.g. AstroZap 4 channels controller) and this is set to low, will the fan rotation decrease?

 

The reason why I ask this is because I would like to leave the fan on while observing, but at a reduced speed.

 

Thanks for your help.


Edited by Piero DP, 28 February 2020 - 07:58 AM.


#2 Couder

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Posted 28 February 2020 - 09:40 AM

DC motors speed depends on the voltage. I helped a friend put motors on his Dob, and we used pots (volume controls) to control the speed. So yes, reduced voltage will run your fan slower. If it is not slow enough, you can add a "pot" to dial in the speed you want. By the way, a pot will reduce the speed but cannot make it any faster than it would be without the pot.


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#3 Piero DP

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Posted 28 February 2020 - 09:58 AM

DC motors speed depends on the voltage. I helped a friend put motors on his Dob, and we used pots (volume controls) to control the speed. So yes, reduced voltage will run your fan slower. If it is not slow enough, you can add a "pot" to dial in the speed you want. By the way, a pot will reduce the speed but cannot make it any faster than it would be without the pot.

Thanks a lot. Very helpful.



#4 SonnyE

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Posted 28 February 2020 - 03:45 PM

DC motors speed depends on the voltage. I helped a friend put motors on his Dob, and we used pots (volume controls) to control the speed. So yes, reduced voltage will run your fan slower. If it is not slow enough, you can add a "pot" to dial in the speed you want. By the way, a pot will reduce the speed but cannot make it any faster than it would be without the pot.

Potentiometer.

You go asking for a pot and you are liable to come home with something to boil spaghetti in. lol.gif


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#5 Piero DP

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Posted 28 February 2020 - 03:55 PM

Potentiometer.
You go asking for a pot and you are liable to come home with something to boil spaghetti in. lol.gif



Aren't the two knobs installed on the astrozap dew controller, potentiometers?

#6 Couder

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Posted 28 February 2020 - 05:49 PM

Yes, pot is short for potentiometers




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