Hi: For such a small amount of power you could consider using an energy limiting Class2 transformer as is/was used in old doorbells. You would have to put a bridge rectifier and bulk capacitor on the output to make DC, but that should be ok given the power levels. If you do this, make sure that the bridge rectifier and capacitor are physically very close to the transformer to reduce problems with diode reverse recovery losses which can stress the parts.
Here's a link to Hammond transformers of that type, although they are no doubt available from many sources at most electrical supply houses. http://www.hammondmfg.com/ba.htm JARMO _____________________________________________________________________________________ Jarmo Venalainen | Schneider Electric | Xantrex Brand | CANADA | Sales Application Engineer Phone: +604-422-2528 | Tech Support: 800-670-0707 | Mobile: +604-505-0291 Email: jarmo.venalai...@schneider-electric.com | Site: www.Xantrex.com | Address: 3700 Gilmore Way, Burnaby, BC V5G4M1 *** Please consider the environment before printing this e-mail From: "Dave" <d...@independentpowerllc.com> To: "'RE-wrenches'" <re-wrenches@lists.re-wrenches.org>, Date: 01/29/2015 10:58 AM Subject: Re: [RE-wrenches] Low wattage 120vac to 24vdc transformer for LED's Sent by: "RE-wrenches" <re-wrenches-boun...@lists.re-wrenches.org> We are renovating a 25 yr old off grid house and one of things being done is to change some 24vDC circuits to 120vac. The only problem that I'm having is finding a low wattage 120vac to 24vdc transformer for a few strings of 24v LED night lights (a few watts each string) that are built into some nice hardwood trim in the bedrooms. I just tested the following device and found that it uses 29 Watts to power a 3W LED. Not an acceptable load for this house. It is labeled as LED Magnetic Transformer by National Specialty Lighting part # TR24L20DC-M20L24DC-AR Input: 120vac, Output 24vdc, Maximum 20W Is there anything else available that will do this job and use a lot less power than 29 Watts? Thanks, Dave David Palumbo Independent Power LLC 462 Solar Way Drive Hyde Park, VT 05655 802-888-7194 ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. ______________________________________________________________________ _______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
_______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org