Orion optics mirror fan

[Neil H]

Hi everyone  does any one know what lead i need to plug in to fan ?

Also i know the fan is 12volt but i am sure i read some were a 9volt pp3 works ?

[John]

I think mine works off a PP3 battery.

I don't use it though.

[Second Time Around]

It's 12 volts.  I recently bought just this small battery (that I velcrod to my rocker box) from Amazon: 

Yuasa NP1.2 – 12 UPS Batteries

https://www.amazon.co.uk/gp/product/B000V3S86Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

To connect the battery to the fan I then bought this from Amazon:

JENOR Dual Red & Black Test Leads with Crocodile Clips Alligator Jumper Cable Wire 105cm

https://www.amazon.co.uk/gp/product/B07MZ1JC1F/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

Hope that helps.

[Neil H]

1 hour ago, John said:

I think mine works off a PP3 battery.

I don't use it though.

Hi John are they not worth getting it working 

 

32 minutes ago, Second Time Around said:

It's 12 volts.  I recently bought just this small battery (that I velcrod to my rocker box) from Amazon: 

Yuasa NP1.2 – 12 UPS Batteries

https://www.amazon.co.uk/gp/product/B000V3S86Y/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

To connect the battery to the fan I then bought this from Amazon:

JENOR Dual Red & Black Test Leads with Crocodile Clips Alligator Jumper Cable Wire 105cm

https://www.amazon.co.uk/gp/product/B07MZ1JC1F/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

Hope that helps

Hi that's cheap battery that's a good idea 

[John]

Well I tried it a few times but found that using it didn't seem to make any noticeable difference either to the cool down time or the performance when cooled

My primary mirror back is quite exposed though - it's one of the older Orion Optics primary cells. Maybe that helps with cooling ?

Quite a small fan as well.

 

[Neil H]

Hi John mine is open like your but fan is a lot bigger about 1/2 the size of the mirror

I will apologise John it's the same size now I had a good look at it 

Edited April 13, 2020 by Neil H
apologise to John

[John]

Give it a try and see if it makes any difference. Nothing to loose as it's already installed

[Second Time Around]

Both my 8 inch and 10 inch OOUKs have semi-closed mirror cells and small fans.

I've always turned the fan on about an hour before observing so have no idea what if any difference it makes.

I also keep the fan on throughout the session - it doesn't seem to cause undue vibration.

[Neil H]

That's sounds like it may be worth a go

[scarp15]

The equipment I have is a 12V 7Ah battery, transformer lead, inverter and charger. This set-up is for my OOUK 14" dob and can be applied to my OOUK 8"dob.

But, I seldom if at all use it, instead trying to remember to charge the battery up every month or so. It created too much vibration if left running with my 14" dob. Perhaps as John has indicated, the primary mirror is quite exposed and can cool down quickly. I guess it may also depend on how you intend to use it, such as how immediately and engage in high power observing. Much as to what I observe tends to be at low to medium/high power. If going to higher power, the dob's are usually at optimum in cooling terms by then. Depending on the size of the mirror, it's a useful facility to have, as mentioned perhaps give it ago, some find it purposeful others less so. 

Edited April 12, 2020 by scarp15

[Neil H]

Hi all hope your all keeping safe , any way I decided to make a lead for the fan in the back of the mirror , as I have used a variable fan speed unit and a 12volt power pack

Edited April 13, 2020 by Neil H

[Neil H]

I just wonder in the summer if  it would blow out the hot air from the OTA