extra cooling

[mahendra]

i normally have some very hot days and want to put some extra fans to cool my classics using the aux on the.What are experts opinion?

[Vic]

Hi Mahendra,

In my opinion,  this is a good strategy.  Cooler is better for most electronics.  We do Air Condition our power rooms,  and have used auxilary fans on each of the OB MX-60s here.  Both of these things reduce the amount of time that the internal fans run on the MXes to about zero.

Had thought about experimenting with a smallish room fan directed on the Classics in use here and give the internal fans a bit of a rest.  Am not saying that this needs to be done,  but  should help them a bit by circuating cooler A/C-ed air over them.

Just my opinions.   Vic

[TomW]

I would agree with vic, more cooling is good.

On my Classics when the internal fan is on I don't see how you could increase airflow much through it. If I were concerned with cooling I would just use a large muffin fan to blow on the case. Mine do get pretty warm on the outside when they are working.

Actually, I doubt it is necessary unless the ambient (room) air is above 120 F or something.

Good luck with it.

Tom

[asmaps]

I have installed a Delta electronics model BFB1024h  24v a bit overkill had it on hand it is running at 11v to lower the air flow the temp drop about 5-7 c, is mounted to one of the entry holes at the bottom, controlled by AUX 1 on PV volts.
Hope this helps.
Peter

[dgd]

I have installed a Delta electronics model BFB1024h  24v a bit overkill had it on hand it is running at 11v to lower the air flow the temp drop about 5-7 c, is mounted to one of the entry holes at the bottom, controlled by AUX 1 on PV volts.

Do you have a photo of this setup that you could post here?

Dgd

[asmaps]

I will give it a go have not attached photo before.
Peter

[Vic]

Believe that much of the heat that a Classic develops is conducted to its metal case.  My plan is to use a 12 inch diameter 120 VAC low-speed fan that gently blows air around the Classics.

Expect to make it a counter-flow fan,  placed above the Classics,  blowing air from the top, down.   Will see how this works.   But probably will take a month or two to try it.

For cooling of the OB MX-60 CCs,  did use a 4-inch 12 VDC Fan blowing into the wiring compartment,  through the opening of the removed bottom cover.  It was controlled by Aux Out,  and worked very well.

Will report results when it is installed.   Opinions,  Vic

[SolarVet]

And how is this connected or setup/powered  from the Aux 1 . Does Aux 1 provide the power I have a 12 volt fan same type.  Just not 24 volt.

[asmaps]

I use the dry contacts setup on AUX1 with a 24v supply driving a 24v relay that supply power to a dc/dc converter that is adjustable (input 4-40v adjustable to 4-32v.3amps)
TCHWAREHOUSE on ebay have them item # 260803246396
I have it on PV high at 105 v with a 900second delay, off PV low 85 v 900second you may fine tune to suite this works well for me.
Peter

[JerryB]

I have found that my classic runs VERY hot when it is operating close to maximum out put (97 amps); in fact it will thermal limit. I have installed an 8" DC fan which blows on the case, controlled by a thermistor and a control circuit I ginned up. Thermistor is attached to the case. My system has a high step-down ration (90 volts to 12 volts), so the controller efficiency is probably affected.

Jerry

[Endurance]

I like the idea of additional cooling. I see one arrangement blowing up from the bottom and the others blowing down from the top. I am thinking that blowing from bottom up would help heat rise. Can anyone think of a good reason to work against the rising heat by trying to force it down?

[JerryB]

The internal fan in the classic feeds air from the top down (I seem to recall), so not fighting the "natural" direction seems appropriate.

Jerry

[boB]

The internal fan in the classic feeds air from the top down (I seem to recall), so not fighting the "natural" direction seems appropriate.

Jerry

The internal 2 fans bring in cooler air from the bottom and point upwards past the electronics.

There has been some info shown that the external turbo fan works slightly better blowing downwards.

boB

[WattsUp]

Do the 2 fans in the bottom run at the same time ?

[boB]

Do the 2 fans in the bottom run at the same time ?

Yes.  The 2 internal fans are powered off the same transistor at about 48 degrees C internal
temperature  and the external turbo fan is powered separately and comes on at around
58 degrees C internal temperature.

They will turn off when the internal temperature drops a few degrees or after a moment
when the Classic goes to Resting.

boB