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Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: mjp24coho on July 29, 2014, 09:09:31 PM

Title: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: mjp24coho on July 29, 2014, 09:09:31 PM
I'm hoping some of you that have experience with the Classic Aux ports can help me.  I have (2) Classic 200's (Follow Me), and I also have a Zephyr vent fan that I use to vent my battery box (24V battery bank).  I have the fan (12V) wired to Aux 1 on my primary Classic, and the Classic is set to turn the fan on when the batteries are over a certain voltage.  When it gets over that voltage, the Classic displays that Aux 1 is "on", but the problem is, my fan doesn't run.  To make sure the fan itself is good, I wired it directly to a 12V battery, and it works fine.  I tried turning my Classic Aux 1 to "On", but the fan still doesn't kick on. I even ran a separate wire from the Aux 1 ports and hooked that up to a voltmeter (when the Aux 1 was set to "On"), and I get no voltage reading.  At first I was concerned that something was wrong with the Aux port on my Classic, but I tried each of the above steps on my second Classic and got the same results.  Surely there must be something I'm missing here.  Can anyone help?  I'm trying to get this resolved ASAP, as it is set up at my remote cabin and I'm leaving tomorrow.

Thanks,
Mike
Title: Re: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: dgd on July 29, 2014, 10:07:06 PM
Hi,
Unless I misunderstand it appears you are trying to power the fan from AUX1
This won't work as AUX1 likely cannot provide enough current to drive the fan.
I seem to remember it can provide 12v at about 200ma, thats under 3watts  :D

You need to use AUX1 to control a power relay, eg ssr, that switches power to the fan

dgd
Title: Re: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: mjp24coho on July 29, 2014, 10:31:26 PM
I thought I had read that the Classic could power the small Zephyr vent fans.  Regardless, if it could power 3W at 12V, wouldn't I at least get a 12V reading when connecting two wires to Aux 1 when it is on?
Title: Re: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: dgd on July 29, 2014, 10:57:34 PM
I'm not sure about direct powering zephyr fans, someone from MN would need to confirm this.
The reason you do not see any voltage is because the fan is like a low value resistance and its pulling the voltage down to zero. A higher resistance lower wattage fan such as one of those CPU types would probably work ok.
When you turn on AUX1 use a voltmeter connected to the aux1 outputs to check voltage with nothing else connected to aux1
dgd
Title: Re: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: mjp24coho on July 29, 2014, 11:18:59 PM
Nevermind!  I should have read the manual first.  You can switch Aux 1 between acting as either a relay or 12V output.  I didn't change the jumpers to have it act as a 12V output.  I switched the jumpers, and now it is powering the vent fan just fine.
Title: Re: Aux 1 (Fan) Doesn't Work - Any Suggestions on What I'm Doing Wrong?
Post by: Halfcrazy on July 30, 2014, 09:24:18 AM
Glad to hear you got it. Those jumpers are the normal culprit. And yes the Classic will power a 12v Zephyr fan great off the Aux direct