220v to 110v step down transformer...

[sureshkn]

Hi,
From going through related posts, I understand that Isolation Step Down transformers are better than the Auto Step Down transformer. I have a Subwoofer that needs 90W and a Amplifier that needs 210W.

Please guide on the below questions.,

- Is 500W stepdown transformer is enough to connect both ?

- Should I really go for Isolation transformer ? Maxine 500W auto costs Rs. 2,650 whereas 500W Isolation costs Rs.4,960.

- Is there any good local transformers available in Bangalore ? Or should I go with Maxine ?

Thanks,
Suresh.

 

[turgid]

Firstly out of my own pursuit into this topic, I am not understanding what do you mean by isolation? Isolation from mains? Perhaps a more experienced FM can answer you more thoroughly. I am not entirely sure why you would pay INR 2650 for a transformer, you can get local made transformer with good wattage for less than 500 bucks. I remember seeing some 240 to 24-0-24 with 5 amp rating that is 120 VA going for 300 bucks. The secondaries are wound according to the step down ratio and then a wire is selected as per its Irms handling capabilities to decide the number of turns for that gauge.

Secondly, out of my own enlightenment in this topic, EI cores have more leakage inductance due to their design and therefore it is much better to use a Torroid or R-core. Both of which are available at a fraction of your cost at diyaudiocart

Best regards,

 

[omishra]

Isolation means primary winding has mains 220V-230V and output 110V is taken from secondary winding. Thus input and out are isolated from each other.

Auto-transformer has single winding which takes fixed input and variable selected output. Thus output is reduced (or stepped up) but still connected to mains directly.

 

[jmascreen]

I recently got the maxine 500W for Xbox 360, the local one was giving burning smell better to go with good one's.
Its always advisable to go with isolated model if your budget permits

 

[pakecc]

In auto transformers, if anything goes wrong in the primary winding, then the output voltage also will become the same as input. To state simply, in a 220 to 110 step down transformer, any malfunction in the input side winding will result iin distribution of 220V in the output side also. Then, have to say goodbye to the connected 110V equipments.

And in isolation, any malfunction in the primary side, then no output at all . Equipments Saved.

Rgds

 

[sureshkn]

Thanks a lot for the explanations.
MX step down transformer says it provides sinusoidal output. Maxine does not say anything like that. So, it means MX step down transformer is better than Maxine ?

 

[davinci]

As per theory, if the input is sine wave, the output should be sine from a step down transformer, so eventually both of the transformer outputs sine wave.....the only difference should be the quality of the transformer.. I have used many Maxine for low voltage applications 220 to 24,18 & 12..they were good. But I haven't used for 110 conversion!