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Re: [EVDL] LED Taillights - a money saver in gas cars?->rangeextenderin EV's? - an an

I don't know of any commercial charger that doesn't have a transformer,
the shock hazard is too great.

There's ones with a 60Hz transformer (which won't work on DC) and then
there's ones with a rectifier and DC cap feeding a high freq "switch
mode" inverter feeding a high freq transformer. The high freq
transformers are far smaller, lighter, and cheaper. That type will
generally work fine on DC input. These are really really common.

The point being that either way it's gonna have a transformer. It'll
look like a transformer either way too, although someone familiar with
them can easily tell the high freq one from the 60Hz one.

Danny

Mike Willmon wrote:

>If it doesn't have a tranformer then it is a switch mode charger, or switcher. The forst thing it does is rectify the AC power
>coming in to make a DC signal that is then puls width modulated to get the correct average voltage the charger calls for. If it
>has a full wave recitifer on the front end it will conduct your DC pack in either direction. (I believe most smart chargers
>employ full wave bridge rectifiers - but I can't promise its always the case). If by chance they skimped on the parts and used a
>half wave rectifier it will work in one direction but not the other. You can test it by putting in a small 5-10 amp fuse coming
>from the pack voltage when hooking it to your charger. You can look on the data plate and see if it lists it as a 90VAC to
>240VAC input. If so then you would be safe with a pack big enough not to sag below 90VDC or with a max charge voltage greater
>240V DC.
>
>Mike,
>Anchorage, Ak.
>
>
>
>>-----Original Message-----
>>From: [email protected] [mailto:[email protected]]On
>>Behalf Of storm connors
>>Sent: Sunday, September 30, 2007 6:50 PM
>>To: Electric Vehicle Discussion List
>>Subject: Re: [EVDL] LED Taillights - a money saver in gas
>>cars?->rangeextenderin EV's? - an analysis PC Power Supply
>>
>>
>>How do you tell if a charger will work on DC? I have a 2-6-10amp Vector
>>charger which does a great job charging 12v batteries. I am not brave enough
>>to plug it into my 144v pack. I hate electronic smoke. It doesn't use a
>>transformer - it only weighs a couple pounds- so I'm guessing it might work.
>>But how does one tell?
>>
>>On 9/30/07, Mike Willmon <[email protected]> wrote:
>>
>>
>>>I've been using one of the Guest 6 amp 12V auto tender chargers for my
>>>Dc-to-Dc. My Aux battery was kinda smallish, it was the
>>>starting battery out of the truck I converted. After 1.5 years it finally
>>>gave up. Now I have about a 75AH battery out of some
>>>medical equipment cart. The 6A Guest recharges it after my daily commute
>>>in less than an hour. It can also plug right into the
>>>120V pack to charge while driving. I relied on this a little when the old
>>>aux battery couldn't keep the headlights for a 10
>>>minute drive. But the Guest charger is potted and I don't worrry about it
>>>getting damp. I've had this charger for near 10 years
>>>now.
>>>
>>>Mike,
>>>Anchorage, Ak.
>>>
>>>
>>>
>>>>-----Original Message-----
>>>>From: [email protected] [mailto:[email protected]]On
>>>>Behalf Of Lee Hart
>>>>Sent: Sunday, September 30, 2007 7:04 AM
>>>>To: Electric Vehicle Discussion List
>>>>Subject: Re: [EVDL] LED Taillights - a money saver in gas cars?
>>>>->rangeextenderin EV's? - an analysis PC Power Supply
>>>>
>>>>
>>>>[email protected] wrote:
>>>>
>>>>
>>>>>Has anyone used a cheap pc-power supply rather than a DC/DC converter
>>>>>
>>>>>
>>>- to
>>>
>>>
>>>>>recharge their 12-volt aux battery?
>>>>>Do you think it would hold up?
>>>>>
>>>>>
>>>>You get what you pay for. The quality is low, the specs wildly
>>>>exaggerate their real performance, and there are performance issues.
>>>>There's been a lot of discussion on this on the EV list in the past (see
>>>>the archives).
>>>>--
>>>>Ring the bells that still can ring
>>>>Forget the perfect offering
>>>>There is a crack in everything
>>>>That's how the light gets in -- Leonard Cohen
>>>>--
>>>>Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
>>>>
>>>>_______________________________________________
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>>>>
>>>>
>>>_______________________________________________
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>>>
>>>
>>>
>>
>>--
>>http://www.austinev.org/evalbum/1059
>>http://stormselectric.blogspot.com/
>>Storm
>>_______________________________________________
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>>
>>
>>
>
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>

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