Reply by Enrico December 10, 20102010-12-10
 > What is the consultancy rate for this?

Hi,

the rate was 2000 Euro for the complete design.

The contract was based on 5 technical meetings at my office of 3 hours
each.

The design was a Flyback Power Supply of 22 Watt with the Viper27LD
(60 KHz) controller.

He also brought me ta sample of the transformer.

Enrico



Reply by Chris H December 10, 20102010-12-10
In message <64c65892-fa37-4ca1-a2b0-8a0df517a3e8@e4g2000vbi.googlegroups
.com>, Enrico <zigbee@libero.it> writes
>Hi, > >I paid a professional to do the design of the power supply and to >transfer his knowledge to me on flyback power supplies. >This guy designed the transformer as well but he is not an expert in >safety regulations about transformers. > >The company who is building the samples for me is Indian. They >proposed me a solution without sleeves. > >I'm looking for documents that explain the most important do's and >don'ts of transformers winding. > >Enrico
What is the consultancy rate for this? -- \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ \/\/\/\/\ Chris Hills Staffs England /\/\/\/\/ \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
Reply by Enrico December 10, 20102010-12-10
Hi,

I paid a professional to do the design of the power supply and to
transfer his knowledge to me on flyback power supplies.
This guy designed the transformer as well but he is not an expert in
safety regulations about transformers.

The company who is building the samples for me is Indian. They
proposed me a solution without sleeves.

I'm looking for documents that explain the most important do's and
don'ts of transformers winding.

Enrico
Reply by 1 Lucky Texan December 8, 20102010-12-08
On Dec 8, 6:36=C2=A0am, Enrico <zig...@libero.it> wrote:
> Hi, > > I have to write the winding specifications for a 20 Watt, flyback > transformer. > > The core selected is an E 25/13/11. > > Current and voltages calculations are ok. > > I have to comply to the following standards: > > IEC950 > IEC335 > IEC61558 for reinforced insulation > > Primary to Secondary Insulation =E2=89=A5 4000V > Primary to Auxiliary Insulation =E2=89=A5 1500V > > I opened a couple of transformers and noticed that there are many > things: > > Triple insulation wire, Enamelled wire, sleeves, shields, insulating > adhesive, Primary splitted in 2 windings, TAP. > > Are there any simple documents around that explains the meaning of all > those things? > > Thanks in advance, > Enrico
Is there gonna be a submission to a testing lab? Maybe build 2-3 different designs and choose from 'winning' submissions.
Reply by Rob Gaddi December 8, 20102010-12-08
On 12/8/2010 4:36 AM, Enrico wrote:
> Hi, > > I have to write the winding specifications for a 20 Watt, flyback > transformer. > > The core selected is an E 25/13/11. > > Current and voltages calculations are ok. > > I have to comply to the following standards: > > IEC950 > IEC335 > IEC61558 for reinforced insulation > > > Primary to Secondary Insulation &ge; 4000V > Primary to Auxiliary Insulation &ge; 1500V > > > I opened a couple of transformers and noticed that there are many > things: > > Triple insulation wire, Enamelled wire, sleeves, shields, insulating > adhesive, Primary splitted in 2 windings, TAP. > > Are there any simple documents around that explains the meaning of all > those things? > > Thanks in advance, > Enrico
Transformer winding specifications, especially when you have to take into account safety/regulatory issues, get complicated. It sounds like you haven't done it before. Whoever you're turning this document over to probably has. Can you ask them? -- Rob Gaddi, Highland Technology Email address is currently out of order
Reply by Enrico December 8, 20102010-12-08
Hi,

I have to write the winding specifications for a 20 Watt, flyback
transformer.

The core selected is an E 25/13/11.

Current and voltages calculations are ok.

I have to comply to the following standards:

IEC950
IEC335
IEC61558 for reinforced insulation


Primary to Secondary Insulation =E2=89=A5 4000V
Primary to Auxiliary Insulation =E2=89=A5 1500V


I opened a couple of transformers and noticed that there are many
things:

Triple insulation wire, Enamelled wire, sleeves, shields, insulating
adhesive, Primary splitted in 2 windings, TAP.

Are there any simple documents around that explains the meaning of all
those things?

Thanks in advance,
Enrico