Fans always running on my new Classic 200

[dapago]

Hello.

When in bulk mode, the classic fans are always running. Is that normal? If i recall well, on my last classic 150, fans where not running all the time.

Any inputs on that matter?

[Vic]

dapago,

A large factor in how often and longs the fans in Classics run is the input voltage.   High input voltage  reduces the efficiency of the CC.   This increases the internal heating in the CC,  so the fans need to run more often and longer,    even at fairly low output currents.

Ambient temperatures that are warm or hot will also be a large factor governing the running of Classic fans.

I have no personal experience with Classic 200s,  but  this CC  will have a bit less efficiency than a Classic 150,  all else being equal.

IMO,   Vic

[dapago]

Vic. That must be it. We just connected 2 more panels increasing the input voltage.

Thanks again

[mike90045]

yep, I found out the same thing, I had to run a higher voltage array, could not stuff any larger wires into the existing conduit,  so went higher voltage.  Now I have fans running too.

[CDN-VT]

Voltage of the system ,voltage & panels supplying the classic
..
If your input is say 225Vdc in & your dropping to a 12Vdc battery system the Classic 200 MPPT is working so hard that heat is normal .

Fan noise is great in my ears , look under temps & read the board & fets , below 60 c , yur doing good . Love that sound !!

VT 

[littleharbor2]

225 volts would be excessive and possibly damaging. Hypervoc would have to kick in.  Typo?

[TomW]

225 volts would be excessive and possibly damaging. Hypervoc would have to kick in.  Typo?

Not sure on the typo bit but the point he is making is that, with very high input to low output voltage The Classic will create more heat than when operated with a lower input voltage for the same output. Conversion losses show up as heat in the controller.

Realistically, you would stay closer to the battery voltage. Seems like 2X to 3X battery volts is a better ratio. Pretty sure the manual has suggestions on that ratio of input to output volts.

Tom

[CDN-VT]

225 volts would be excessive and possibly damaging. Hypervoc would have to kick in.  Typo?

Nope , making  sure folks are  catching me .

[Jacotenente]

Didn't know that (high PV panel volts = more fan run time). I have two 150's and one 200. The 200 fans rarely come on with 1,305 watts of PV (around 60v PV). However, the 150 with 2,400 watts and "nominal" PV input voltage of around 100 volts...fans run more often. I have some aluminium wedges installed behind the Classics to help with heat/airflow. Overall, my solar power "layout" where I mounted everything could use some improvement...which will help with cooling. I am glad the Classics fans blow out heat...beats the alternative! (like melting into a pile of goo)

[Westbranch]

I currently have a newer Classic 150, #29,032 that replaced a CL150 with a 4 digit model and since I installed the new one I hear the fans turning on when ever I have incoming 1300+W ie a good load of amps and voltage, the CL is taking ~70 V and down shifting it to ~ 25+V. Amps go >50 just before it hits Absorb. Usually happens just after noon.

This fan makes more noise than the old one, it rattles a bit.
No where near as bad as the 'woodpeckering' from my older Kid (now replaced, Thanks Ryan).

[TomW]

This fan makes more noise than the old one, it rattles a bit.

Unless they changed how they attach the fans there was a "fix" for noisy fans where you apply a bead of silicone caulk along the plastic shroud that could be loose and buzz / rattle. I did it on one some years ago and it worked treat!

Just from memory.

Tom

[Westbranch]

thanks tom, saw that video, but I am avoiding the task of dismantling the Classic from the E-panel to access the rear of the Classic...  it's in an awkward position to access now.

[TomW]

thanks tom, saw that video, but I am avoiding the task of dismantling the Classic from the E-panel to access the rear of the Classic...  it's in an awkward position to access now.

I just had to pull the front off. 4 screws and it exposed that turbo cover thing?

The recessed Stainless Steel screws are easy to drop in tight installs.  They don't stick to a magnetic screwdriver, and mine got under the pallet the battery was on so didn't see them until we dismantled that system. Next time I had to pull the hard to get at front screws I used some bearing grease on the screwdriver and the screws stuck to it pretty well.

Best of luck with it!

Tom

[Westbranch]

Ah Ha, I think we are talking New Chassis vs OLD chassis. there is now a plate on the back of the new classics that simplifies re & re of the fans.

http://www.midnitesolar.com/video/videoPlay.php?video_ID=78&videoCat_ID=18

[TomW]

Ah Ha, I think we are talking New Chassis vs OLD chassis. there is now a plate on the back of the new classics that simplifies re & re of the fans.

http://www.midnitesolar.com/video/videoPlay.php?video_ID=78&videoCat_ID=18

Yep, my Classics are all older units and have been out of service for 2 years, to boot. A bit like me, haven't done much of anything since I was taken out of service. AKA retired.

BTW, that video link comes up "not found"

Tom