transformer question again - Electronic Circuits Projects Diagrams Free

andy257 · 12th February 2004, 05:54 PM

Hi Guys

i have been looking to source a transformer which will convert 240Vac to 12Vac. However the 12V side must have a current rating of 5amps. Basically what iam going to do it reverse the transformer around so that it becomes a step up instead of a step down. (is it easier this way?) I am using it in an inverter circuit and i hope to have around 60Watts (60 / 12 = 5 Amps)

My question is:

looking on rs components web site they show specs of transformers with 2 * 6V or 2* 12V etc on the output side. Why do they do this? If i want my 12V do i go for one with 2* 12V and only use one or do i go for one with 2* 6V? and use both to get my 12V?

any help is greatful

cheers
andy.

Sebi · 12th February 2004, 06:34 PM

Here is two causes why made the manufacturers two windings:1. the PCB transformers for low profile the primary and secondary 2-2 independent windings, 2*120 and 2*12 etc. 2.With two secondary need only two diodes for full-wawe rectification.
If You need really only one 12V, choose the 2*6V type and connect the secondaryes serial.
For an inverter (from 12VDC to 220VAC) also better the two secondary type, in this case need only two power transistors, but i recommend the 2*9V secondary.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

12th February 2004, 05:54 PM	(permalink)
andy257	transformer question again Hi Guys i have been looking to source a transformer which will convert 240Vac to 12Vac. However the 12V side must have a current rating of 5amps. Basically what iam going to do it reverse the transformer around so that it becomes a step up instead of a step down. (is it easier this way?) I am using it in an inverter circuit and i hope to have around 60Watts (60 / 12 = 5 Amps) My question is: looking on rs components web site they show specs of transformers with 2 * 6V or 2* 12V etc on the output side. Why do they do this? If i want my 12V do i go for one with 2* 12V and only use one or do i go for one with 2* 6V? and use both to get my 12V? any help is greatful cheers andy.

12th February 2004, 06:34 PM	(permalink)
Sebi	Here is two causes why made the manufacturers two windings:1. the PCB transformers for low profile the primary and secondary 2-2 independent windings, 2120 and 212 etc. 2.With two secondary need only two diodes for full-wawe rectification. If You need really only one 12V, choose the 26V type and connect the secondaryes serial. For an inverter (from 12VDC to 220VAC) also better the two secondary type, in this case need only two power transistors, but i recommend the 29V secondary.