maybe i'll just leave the fan as is.. just a bit annoying charging 300mah batteries and having it run at full blast. if it's possible i will try to add some type of control knob or switch.. unless someone actually has tried a specific fan
i don't think it's worth ordering some random fan only to find out it's just as loud.

in any case.. was going to buy some bullet posts, but came up with a similar approach, i soldered some bullet connectors instead and whala

Try shorting pin 4 (fan) to pin 8 (gnd). It sounds like a cat purring. That's what I did and I am happy with the results.

Around 12K Ohm to 15K Ohm resistor slows the fan enough that it still has sufficient air flow but is not screaming loud.

Remember these things are designed to run in a data centre and the PS is the last user of the cool air that is sucked in from the front of the server. By the time they get the air, it is already warm from the HDD's and CPU's.

Cheers
whitedg

Sorry if this is the wrong thread to ask this question but I bought a 24v power supply from a guy from my airplane club who is no longer active and I'm having start-up issues. A couple of months ago my power supply no longer turned on right away when the power switch was turned on, the lag time gradually increased from 10-15 seconds to 10-15 minutes and now it wont fire up at all and just makes this slow clicking noise like it's trying but never fires. So my question is if anyone has ever experienced something like this and is there an internal part that normally goes bad preventing these power supplies from turning on that can be replaced. I realize this is sort of like trying to describe funny noises to an auto mechanic and expecting a fix but It's a very nice set-up in a wood box with power poles for 24v and banana plugs for 12v so I'm trying to decide if this thing is salvageable.

Thanks

Do both units have this delay when tested individually? Has a potentiometer been installed between pins 3, & 9? Lastly, what voltage is your power supply putting out once it gets running?

I tore the box apart the power supply was in last night and to my surprise it was one very large Omega 24v unit, I had guessed it was 2 units connected because you could see a large gauge jumper connecting two banks and a separate 12v side. I don't have a potentiometer and if I remember correctly my hyperion showed nearly 25v when it was running. I don't want to clutter this thread and I haven't had a chance to look up the part number on the omega.

Originally Posted by scub

maybe i'll just leave the fan as is.. just a bit annoying charging 300mah batteries and having it run at full blast. if it's possible i will try to add some type of control knob or switch.. unless someone actually has tried a specific fan
i don't think it's worth ordering some random fan only to find out it's just as loud.

in any case.. was going to buy some bullet posts, but came up with a similar approach, i soldered some bullet connectors instead and whala

The best idea I've seen by far!!

does anyone have any problems with chargers not fully charging the packs when using the HP supply? i try two different chargers and while connected to the HP supply my packs are being charged to only 4.17v max. this sort of leads me to believe there is something wrong. i voltage coming out the supply is 12.6v.

Did they charge to 4.2v on another supply or car battery?
Do you have a benchmark?
Perhaps your packs are getting tired?

Rick

they charge to 4.2 on other wall-wart charger and packs are good shape. so the reason i believe something is wrong with the HP supply output is i tried two different chargers on it, a hyperion and accucel and both are doing the same thing... charging packs/cells to only 4.17

Rick is right.

The phenomena that you're experiencing has nothing to do with the source supply and everything to do with the internal resistance of the packs and set charge rate.

Besides, 4.17V/cell is MUCH better for your packs in the long run at the expense of a few seconds of flying.

Mark

i've tried 6 different batteries with different capacity, a $40 charger, a $200 charger, different wiring,etc. i'm aware 4.17v and 4.20v isn't much but it's not really the point.
not beating horse here, time to find another supply to test..

Would be curious to know all details of your testing (ambient temperature, charge rate, etc.) to have a better understanding. The DC output of the charger should be completely decoupled from whatever voltage ripple may be present on the input powerform by the DC-DC converter and input capacitance, to the point that it won't matter. As such, all other factors being equal, termination voltage should be identical.

Mark

I have a couple of the ESP135, PS-3601-1C power supplies which I am trying to float the ground in the second one in order to get the 24VDC output. I read eariler in the thread that this could not be done with this power supply. Thread report #530 indicates that it can be done. Do you happen to have a photo of the mod and whether your kit will support PS-3601-1C

After posting thread #719 I did a little more testing with the ESP135, PS-3601-1C power supplies. Both have pins 6,9,& 10 connected to a single pole switch in order to turn the power supplies on and off. Even though the PS-3601-1C is the same as the DPS-600PB power supply the internal circuit board is different. Floating the ground on the second power supply is easier on the PS-3601-1C than the DPS-600PB. Looking from the rear remove the aft left screw from the circuit board, just the opposite from the DPS-600PB. Their are no wires to cut. You can verify your ground is floated by putting one side of you own meter in the negative output and the other on the case. Wnen both were connected up to a Thunder Power 820 Charger, I had a 25VDC input. I placed a piece of insulation between the two power supply cases and taped them together and placed them in a Pellican Case with the TP 820 Charger.