AEVA Forums

G'day people,

As you may be aware my battles with chargers seem to be a never ending story! I have used both TC/Elcon chargers and KPES (Kingpan) chargers and have had both types fail at various stages. At present I have a 2kw (or is that kW? - I should have checked Weber's post before I started writing this post) KPES charger in the car. I also have 2 more KPES chargers coming from China in the next few days. One is a 1.5kW charger and the other is a 2kW charger. The 1.5kW charger will go under the bonnet and be used in conjunction with the existing 2kW charger to charge at public charging stations and the new 2kW charger will sit in the boot in case the other two blow simultaneously as has happened before.

I prefer the KPES chargers as they are open to the air at both ends. One end of the charger has two large exhaust fans which turn on at a predetermined temperature and a vent at the other end which allows air to flow into the charger to replace the air exhausted by the fans. I realise that this means water can get into the chargers more easily than with fully enclosed chargers but it does allow the chargers to heat up less quickly. The vent end of the chargers is as per the following photo:
As we are coming into our summer months I am worried about the chargers overheating and am thinking about adding a small fan to the "vent" end of these chargers to help force air into the charger. Maybe this would get more air through the charger rather than just relying on the exhaust fans drawing air through. It should look like the following photo:
I suppose I have a couple of problems with my own plan above:

a) The body of the fan on the vent will actually close off two of the "slits" in the vent which may allow less air to get through the vent? Any opinions?

b) I think(?) the existing exhaust fans are turned on at 40 degrees C but I can't find where I got that figure from? I will wire up the new smaller fan with a thermal switch but the only one I can find near to 40C is the Jaycar switch which turns on at 50C. Therefore a possible scenario could be that the charger reaches 40C, the exhaust fans turn on and attempt to draw air out, The fan at the vent end of the charger won't turn on until the temp reaches 50C. So, until the charger's temperature reaches 50C, the exhaust fans won't be able to get much air out?

Of course I will add heat sinks to the top of these chargers as well.

Any opinions?

Thanks in advance for your help.

Cheers Paul

I'm often surprised when folks will install an air-cooled TC charger directly underneath the hood of the car, or buried deep inside the boot. These things get seriously hot!

The fan should work well, just be aware of any dust accumulation. It might not be that difficult to cut a couple of sections out and open it up a bit. And there is no harm to running the fans full time, or at least whenever it's charging.

Centrifugal fan with a cowling over all the intake vents.

Thanks guys

jonescg - yeah good ideas and I never even thought about dust getting in.

Richo - I assume the fan in your picture is something like the "Fan Blower, Scircoco Ace 76 Series 109BD12HA2(HC2)[HD2" available from Element14?

Regards
Paul

My TC charger has a huge heatsink on top with 2 x 12v fans wired in series. I ended up finding a wall wart that put out 12vdc so I could add it to the 240vac power supply side from the outside plug in point in the side of the car. Now the fan starts up when I plug it in rather than when it feels like it. This has reduced the number of times I've needed to shut down reboot the charger to get it going again.
With the RV lithium battery chargers I fit along with a house battery system, I often flip the fan over so it pushes air into the charger rather than trying to suck it out. The outside casing gets hotter but the actual components inside run cooler. It is very important to ensure the hot air exhausting from the charger can not be drawn back in by the fan but rather dumped outside via the air vents if possible. I've had to fit car type paper air filters to the in take side of a few inverters that were in rather dusty environments, the best one was a modified Holden Barina air filter housing with a fan in the top so it sucked cold air from under the vehicle and pumped it into the electrical locker in the front of the van. Outlets up high each side and one fan assisted into the upper boot area. This movement of air through the compartment cooled it down substantially and stopped the inverters and solar controllers shutting down due to overheat.

T1 Terry

Thanks T1 Terry. Good ideas!

I hadn't thought of air filters either so this morning I will be off to my local car spare parts place to see what they have.

Thanks again
Paul

Paul9 wrote: ↑Fri, 20 Sep 2019, 09:12 Thanks T1 Terry. Good ideas!

I hadn't thought of air filters either so this morning I will be off to my local car spare parts place to see what they have.

Thanks again
Paul

Something simple like the round air filter from the old 6cyl Holden is a big enough area to fit fans inside and cheap as chips. The wreckers is another good spot to look at different types of air filter housings to see if something looks like it would fit in well .... then check out the replacement element cost, some of them can be rather expensive, but then again it would really only be a 1 off.

T1 Terry

I use the filters for desk fans.
https://www.altronics.com.au/p/f1024-su ... th-filter/

Paul9 wrote: ↑Thu, 19 Sep 2019, 13:58 I assume the fan in your picture is something like the "Fan Blower, Scircoco Ace 76 Series 109BD12HA2(HC2)[HD2" available from Element14?

https://au.element14.com/w/c/cooling-th ... rt=P_PRICE
Yes but any small one will do.

My idea was to place it flat like your current fan - but off to one side.
Put a filter over the intake hole on fan.
Then put a cowling from the side vent on the fan over the vents slots in the charger.

Thanks T1 Terry and Richo

Your suggestions have given me a few things to explore! I think I might sit down, grab a glass of red and think through this a bit more.

Regards
Paul

Just a thought, they made small diameter paper filters for minis and other Leyland product as well as aftermarket filters, mainly aimed for use with SU and CD Stromberg type carburettors. One of those on Richard's drum fan suggestion would fit easy enough, but if you have a 12vdc supply available you can score there type fans from a wreckers as these are the fan of choice for the heater air circulation in just about every make and model

T1 Terry