Step Down Transformer Recommendation for AVR

[Ooty_hometheater]

Hello All - I purchased Denon X3700H AVR from US. The power spec says 120 v, 60 Hz and 660 Watts. Can you please recommend a good step down transformer preferably with a stabilizer from your experience?

Thanks much for your help

 

[jsmithe]

For stepdowns https://maxineindia.in/ They also sell via Amazon and Flipkart. The stepdowns from Maxine don't have stabilizers. If you are looking for servo stabilizers, look up https://www.vertexpower.in/

 

[jbkar]

The preferred one is an isolation transformer with copper windings

 

[Ooty_hometheater]

Thanks Much

 

[Shanmugam]

You can try bluebird step down transformer. Many brands have come due to sudden increase in oxygen concentrator usage.

Maxine is a very old and reliable brand

 

[frend2001]

Hello All - I purchased Denon X3700H AVR from US. The power spec says 120 v, 60 Hz and 660 Watts. Can you please recommend a good step down transformer preferably with a stabilizer from your experience?

Thanks much for your help

Hi,

You have to take a few things into consideration.

Your choice should have atleast double power rating to your equipment. Now they come with ratings in VA.

I think you should atleast go for a stepdown rated at 1kVA.

Do note your average line voltage as well. Stepdown transformer work on ratio of input voltage to output voltage.

For example they deem the input voltage to be 220v and will give an output voltage of 120v. So the ratio is 1.83 : 1.

If you are getting 245v voltage at your place then the output of your stepdown will be 133v which is 10% higher then rated input.

It stresses the power supply and ultimately something gives.

So please bear this in mind.

Hope this helps

 

[Parag Karani]

Hello All - I purchased Denon X3700H AVR from US. The power spec says 120 v, 60 Hz and 660 Watts. Can you please recommend a good step down transformer preferably with a stabilizer from your experience?

Thanks much for your help

Aulten step down transformer is excellent and it's safe , I did lot of research and then got a satisfactory resolution from Aulten executive,
You can contact Aulten executive @ 9811597709 on Whatsapp, share your requirement and then the executive will check for a compatible product for you.
The Aulten transformer are non humming and come with excellent quality.
I hope this helps,
Regards

 

[Subbu68]

Hello All - I purchased Denon X3700H AVR from US. The power spec says 120 v, 60 Hz and 660 Watts. Can you please recommend a good step down transformer preferably with a stabilizer from your experience?

Thanks much for your help

The frequency is also critical. The voltage ratio of the step down trafo has to include a factor of 50/60. Else transformers in your A/V gear will overheat running at lower frequency and can burn out. This applies to those gear from Japan, Korea etc.too.

Simplest solution is to know the specification of the transformers inside and change to a 240V, 50Hz / secondary voltage (you need to open the equipment and find out) transformers.

 

[Parag Karani]

The frequency is also critical. The voltage ratio of the step down trafo has to include a factor of 50/60. Else transformers in your A/V gear will overheat running at lower frequency and can burn out. This applies to those gear from Japan, Korea etc.too.

Simplest solution is to know the specification of the transformers inside and change to a 240V, 50Hz / secondary voltage (you need to open the equipment and find out) transformers.

Click to expand...

I got a quality transformer from Aulten, my requirement was for USA product, so had a long chat with Aulten executive, just to confirm the product compatibility and quality, they are very good at providing resolution and transformer quality is excellent.
You can contact Aulten voltage converters at 9811597709, you can chat with them on Whatsapp also.
Hope this helps,
Regards

 

[Subbu68]

I got a quality transformer from Aulten, my requirement was for USA product, so had a long chat with Aulten executive, just to confirm the product compatibility and quality, they are very good at providing resolution and transformer quality is excellent.
You can contact Aulten voltage converters at 9811597709, you can chat with them on Whatsapp also.
Hope this helps,
Regards

If they designed the transformer it's good for you, if they have not taken care of change of frequency rating, you can expect overheating of your equipment. Transformers are frequency dependent. In fact any a.c. equipment - motors, fans, transformers.

 

[Parag Karani]

If they designed the transformer it's good for you, if they have not taken care of change of frequency rating, you can expect overheating of your equipment. Transformers are frequency dependent. In fact any a.c. equipment - motors, fans, transformers.

They are branded transformer building company, they understand your requirement and then suggest best compatible product matching your specs and requirements, must interact with them in detail, that is how I installed one for my Dolby atmos AVR and speakers set

 

[Subbu68]

They are branded transformer building company, they understand your requirement and then suggest best compatible product matching your specs and requirements, must interact with them in detail, that is how I installed one for my Dolby atmos AVR and speakers set

It is not for any argument if they are reputed or not, with 30 plus years experience in dealing with suppliers supplying small distribution boards or filter transformers to world class companies making transformers as large as a 3bhk house I have a fair idea where they can play.

If this company did a proper design that's well and good.

 

[Parag Karani]

It is not for any argument if they are reputed or not, with 30 plus years experience in dealing with suppliers supplying small distribution boards or filter transformers to world class companies making transformers as large as a 3bhk house I have a fair idea where they can play.

If this company did a proper design that's

It is not for any argument if they are reputed or not, with 30 plus years experience in dealing with suppliers supplying small distribution boards or filter transformers to world class companies making transformers as large as a 3bhk house I have a fair idea where they can play.

If this company did a proper design that's well and good.

You can contact Aulten and share your requirement, and you can decide, whether they are good enough.
My personal experience was better, after detailed discussions and then, they suggested one of their product.
I hope this solves your concern.
Regards

 

[Subbu68]

You can contact Aulten and share your requirement, and you can decide, whether they are good enough.
My personal experience was better, after detailed discussions and then, they suggested one of their product.
I hope this solves your concern.
Regards

I have no concerns, my equipment are all rated for 240V. I would rather change the power transformer inside the AV equipment than get these stepdown trafos.

Or I'd check if the audio equipment I buy is multi voltage compatible. My 22 yr old Yamaha amp had a switch. My tape deck and CDP has it. My DIY amp has taps to adjust the input voltage from 100V, 120V, 220V, 230V and 240V.

Being an experienced electrical engineer, I could see an important aspect of frequency compatibility being missed. If you are open to know why, read on.

If you use a 100V, 60Hz transformer on 100V, 50Hz (you cannot change frequency without employing some frequency converter) the ratio of V/f changes from 1.667 to 2. This means more magnetizing current, more heat and overheating. The converse is fine as the transformer runs at lower V/f ratio and cooler.

If the manufacturer has compensated, well and good.

 

[rrunner]

I have no concerns, my equipment are all rated for 240V. I would rather change the power transformer inside the AV equipment than get these stepdown trafos.

Or I'd check if the audio equipment I buy is multi voltage compatible. My 22 yr old Yamaha amp had a switch. My tape deck and CDP has it. My DIY amp has taps to adjust the input voltage from 100V, 120V, 220V, 230V and 240V.

Being an experienced electrical engineer, I could see an important aspect of frequency compatibility being missed. If you are open to know why, read on.

If you use a 100V, 60Hz transformer on 100V, 50Hz (you cannot change frequency without employing some frequency converter) the ratio of V/f changes from 1.667 to 2. This means more magnetizing current, more heat and overheating. The converse is fine as the transformer runs at lower V/f ratio and cooler.

If the manufacturer has compensated, well and good.

Which is the simplest method to check the output frequency of step down transformer.(without the need of an oscilloscope)
Will an AC clamp meter work for that purpose?

 

[rrunner]

I am pretty sure a vast majority of coil type voltage step down convertors available in india don't provide 60hz output. It will have its drawbacks like reduced performance or life of the product being used.

 

[Subbu68]

Which is the simplest method to check the output frequency of step down transformer.(without the need of an oscilloscope)
Will an AC clamp meter work for that purpose?

I am pretty sure a vast majority of coil type voltage step down convertors available in india don't provide 60hz output. It will have its drawbacks like reduced performance or life of the product being used.

You cannot change the frequency. The electricity system decides it not any transformer. Or you must use a frequency converter to change it.

Still with a multimeter with frequency measurement option one can measure it. It will show the same at input and output.

 

[mbhangui]

You cannot change the frequency. The electricity system decides it not any transformer. Or you must use a frequency converter to change it.

Still with a multimeter with frequency measurement option one can measure it. It will show the same at input and output.

Indeed. You cannot change the frequency without spending a lot on a frequency converter. The frequency is fixed for the country. For India it is 50 Hz. For US it is 60 Hz.

 

[rrunner]

When you use a 110v 60hz rated drill machine on step down transformer with 110v 50hz output you will notice the difference in speed(lower) as well as burning/overheating smell from coil early on compared to 60hz for what it is designed for. I consciously make it a point not to run such high speed devices for more than 15 minutes at a stretch. same thing applies for vaccum cleaners as well as mixie.

 

[Subbu68]

When you use a 110v 60hz rated drill machine on step down transformer with 110v 50hz output you will notice the difference in speed(lower) as well as burning/overheating smell from coil early on compared to 60hz for what it is designed for. I consciously make it a point not to run such high speed devices for more than 15 minutes at a stretch. same thing applies for vaccum cleaners as well as mixie.

More magentising current , more heat and lower frequency. Speed of AC motors are dependent on frequency. Lower the frequency, lower speed. That how they control motor speeds in industries. VFD - Variable Frequency Drives