Classic 250 fan options...

[Mechanicalbird]

Hi all,
I ordered a 24v computer type fan to help keep my classic cool. My batt bank is 24v. Can anyone suggest a way to wire the fan so it comes on when triggers by Aux 1? Thanks!

[Vic]

It is not clear to me that an external fan,  blowing air onto a Classic will do very much at all,  to keep it cool,  or make it much cooler.   It might cause a small reduction in its operating temperatures.

One way to make power electronics (and batteries for that matter),  is to place them in a coolish environment.   Or,  perhaps condition the space where these items are located,  as do the most demented among us (such as myself).

IMO,  Good Luck.     Vic

[boB]

What are the TEMPs readings ?  FET and/or PCB temperature.

boB

[Mechanicalbird]

The system is in a room that is usually in the 80-90°F during the hottest days of summer. The highest temps I've seen on the classic are 65-70°C. I know that's not really running hot but it can't hurt to keep it a little cooler when drawing heavy loads.

I have to disagree about the fan not doing much. I put the fan right in front of the top vent of the classic pulling air out and it cooled over 5°C in a matter of 2 minutes. When I reversed the fan to push air into the classic the temp actually rose. Weird.

[Vic]

The system is in a room that is usually in the 80-90°F during the hottest days of summer. The highest temps I've seen on the classic are 65-70°C. I know that's not really running hot but it can't hurt to keep it a little cooler when drawing heavy loads.

I have to disagree about the fan not doing much. I put the fan right in front of the top vent of the classic pulling air out and it cooled over 5°C in a matter of 2 minutes. When I reversed the fan to push air into the classic the temp actually rose. Weird.

The result of the fan pulling air from inside the Classic is not surprising,  at all.

You had not described how you intended to us the fan ...  I should have asked.  There was a Thread here,  several years ago,  where a Classic user used a small blower to force additional air into the Classic,  and this resulted is reasonable cooling.

But forcing air into or pulling it out of the Classic is  a bit of an Engineering puzzle,  which needs to integrate with the thermal management already engineered into the Classic.  One also needs to,  perhaps,  consider what could happen when/if this added cooling happens to fail  --  what will be the effect of this on the Classic's existing cooling design.

Generally,  computer type fans have little restriction,  so if/when that added fan fails,  it should cause little restriction,  but the way that any added fan could affect the airflow of the existing air flow,  negatively.

Having power electronics is a reasonably cool environment will  improve battery life hugely  --  for every 10 degree C increase in battery temperature (above some reference)  will halve battery life.

In general,  batteries are more negatively affected by high ambient temperatures,  than are electronics.

A cool environment is much better for the whole power system,  of course.

Not to argue,  though.    Good Luck,   Vic

[Mechanicalbird]

Thanks Vic. Hopefully, One of these days I'll be able to run the AC all day instead of just when the batts are fully charged and the sun is shining bright! Until then....

[Vic]

The first Summer that our power system was on-line,  there was NO A/C for the power room.   The battery temp ran in the high 80s F for a few weeks ...  not the end of the world.

Started using A/C later that summer,  and that has helped a lot,  although,  is seems Nutso to some.  This A/C does kill efficiency a bit!

Most of us take small steps,  when we can.  Good Luck,   Vic