Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

230vac to 15vac
230vac to 15vac
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 6th November 2019, 08:47 PM   #1
fanaticz is offline fanaticz
diyAudio Member
Join Date: Nov 2019
Default 230vac to 15vac

I have two speaker protection boards by JLester which needs 15VAC 1A each.

What do I need? I believe it's enough with a transformer that has 15VAC secondary, and no other components what so ever. But I ask because I'm not sure. No diodes , protection, anything?
  Reply With Quote
Old 6th November 2019, 08:59 PM   #2
MarcelvdG is offline MarcelvdG  Netherlands
diyAudio Member
Join Date: Mar 2003
Location: Haarlem, the Netherlands
You would probably need a fuse to ensure your house won't burn down if the transformer or the speaker protection board should develop a short circuit.
  Reply With Quote
Old 6th November 2019, 09:02 PM   #3
fanaticz is offline fanaticz
diyAudio Member
Join Date: Nov 2019
Haha, I figured, but thanks for reminding me. I was just curious if the transformer itself actually is enough. My ignorance feels like something else is missing.
  Reply With Quote
Old 6th November 2019, 09:13 PM   #4
PRR is offline PRR  United States
diyAudio Member
PRR's Avatar
Join Date: Jun 2003
Location: Maine USA
To keep it simple: Yes, if you have 230VAC and the load wants 15VAC, you only need a 230VAC:15VAC transformer of appropriate size.

To also keep you safe, you want a fuse so a fault does not heat-up your line cord, set the carpet on fire, burn-up your house. And a box so your child/cat does not touch live wires. You may also want a switch. In some lands a commercial product must use a 2-pole switch. If the box is metal (plastic boxes should be Approved for hiding live wires, so not a cookie-tray) and you have a 3rd pin (PE, green wire) on your wall outlet, there should be a substantial bond from wall 3rd pin to bare metal on the box, so a loose wire will blow the fuse in the basement before anybody gets shocked.
  Reply With Quote
Old 6th November 2019, 11:39 PM   #5
MAAC0 is offline MAAC0  Portugal
diyAudio Member
Join Date: May 2010
Are there regulators on board ? Perhaps You will need not 15V AC, but slightly a couple of Volts more in order for them to work. For example a 7815 needs more 3V on the input.
  Reply With Quote
Old 7th November 2019, 04:32 PM   #6
DF96 is offline DF96  England
diyAudio Member
Join Date: May 2007
He says the circuit needs 15V AC. If that is what the designer has asked for then he will already have taken account of what the DC arrangements are.
  Reply With Quote
Old 7th November 2019, 04:46 PM   #7
Osvaldo de Banfield is offline Osvaldo de Banfield  Argentina
diyAudio Member
Osvaldo de Banfield's Avatar
Join Date: Dec 2011
Location: Barrio Garay,Almirante Brown, Buenos Aires, Argentina
A transformer rated for 15VA (15V, 1A) will not burn any house still under shortcircuit conditions. The finest of the primary winding will act as a self fuse. In any case, external fusing and or a thermal cutout is recommended.
Osvaldo F. Zappacosta. Electronic Engineer UTN FRA from 2001.
Argentine Ham Radio LW1DSE since 1987.
  Reply With Quote
Old 12th November 2019, 08:28 PM   #8
CBS240 is offline CBS240  United States
diyAudio Member
CBS240's Avatar
Join Date: Aug 2005
Location: Smoky Appalachia
Always provide a disconnect. I'm sure even the 15VAC transformer costs more than a fuse. Also, there are better smells than that provided by burnt insulation.
All the trouble I've ever been in started out as fun......
  Reply With Quote


230vac to 15vacHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
120VAC-15VAC split power supply Bradford336 Power Supplies 6 28th October 2012 11:30 AM
Would this work? (15VAC to 12VDC & 24VDC) diyguitarmods Power Supplies 16 6th May 2011 10:04 AM
WTB: 120VAC->15VAC 80VA transformer 454Casull Swap Meet 0 25th October 2008 04:01 AM
F1 at 15VAC instead of 18VAC? nightfire Pass Labs 2 17th October 2006 12:06 AM

New To Site? Need Help?

All times are GMT. The time now is 10:30 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio