Welcome to the Piano World Piano Forums
Over 2.7 million posts about pianos, digital pianos, and all types of keyboard instruments
Join the World's Largest Community of Piano Lovers (it's free)
It's Fun to Play the Piano ... Please Pass It On!

SEARCH
Piano Forums & Piano World
(ad)
Best of Piano Buyer
 Best of Piano Buyer
(ad)
Piano Life Saver - Dampp Chaser
Dampp Chaser Piano Life Saver
Find a Professional
Our Classified Ads
Find Piano Professionals-

*Piano Dealers - Piano Stores
*Piano Tuners
*Piano Teachers
*Piano Movers
*Piano Restorations
*Piano Manufacturers

Advertise on Piano World

(ad)
Accu-Tuner
Sanderson Accu-Tuner
Who's Online Now
97 registered members (Bruce In Philly, 20062007, amyram, anotherscott, albydooby, Boylan, 29 invisible), 1,093 guests, and 540 spiders.
Key: Admin, Global Mod, Mod
(ad)
Estonia Pianos
Estonia Pianos
Quick Links to Useful Piano & Music Resources
Quick Links:
*Advertise On Piano World
*Free Piano Newsletter
*Online Piano Recitals
*Piano Recitals Index
*Piano & Music Accessories
*Live Piano Venues
*Music School Listings
* Buying a Piano
*Buying A Acoustic Piano
*Buying a Digital Piano
*Pianos for Sale
*Sell Your Piano
*How Old is My Piano?
*Directory/Site Map
*Virtual Piano
*Music Word Search
*Piano Videos
*Virtual Piano Chords & Scales
Previous Thread
Next Thread
Print Thread
Hop To
Page 2 of 2 1 2
Re: Moving an MP11SE [Re: jackifus] #2818469 02/21/19 04:31 PM
Joined: Jun 2013
Posts: 365
M
Marcos Daniel Offline
Full Member
Offline
Full Member
M
Joined: Jun 2013
Posts: 365
Since the manufacturer puts the jumper there, of course they must have taken into account the AC frequency, this is the photo of the board, right side of the picture (this is an MP10 I guess MP11SE has something similar inside)
[Linked Image]

(from nekid pichures thread)

Last edited by Marcos Daniel; 02/21/19 04:31 PM.

Pianoteq / Kawai CL 35 & MP11 / Old 1920's Upright Zimmerman
(ad) SWEETWATER Lowest Prices
Re: Moving an MP11SE [Re: Marcos Daniel] #2818481 02/21/19 04:46 PM
Joined: Jul 2014
Posts: 1,886
JoeT Offline
1000 Post Club Member
Offline
1000 Post Club Member
Joined: Jul 2014
Posts: 1,886
Originally Posted by Marcos Daniel
Since the manufacturer puts the jumper there, of course they must have taken into account the AC frequency

There is nothing to "account" for. A transformer like the one you see on the bottom is either made for 50 Hz or 60 Hz (or for 20 kHz like the small ones in switching PSUs).

It takes in whatever you feed it with (it has not other choice, it's a transformer after all, not a power line diagnose system), but at the wrong frequency it will simply produce excess heat and fail at some point. At the wrong voltage, it will simply output a different voltage (and fry whatever is behind it). Voltage can be corrected by simple means (another transformer in front of it or different tap), but if the transformer runs at (wrong) mains frequency, there is nothing you can do about it, except for replacing it.


Yamaha P-515 | Kawai ES100 | Steinberg UR22 | Sony MDR-7506
Re: Moving an MP11SE [Re: jackifus] #2818521 02/21/19 06:01 PM
Joined: Aug 2011
Posts: 6,262
J
JohnSprung Offline
Unobtanium Subscriber
6000 Post Club Member
Offline
Unobtanium Subscriber
6000 Post Club Member
J
Joined: Aug 2011
Posts: 6,262

The thing with transformers isn't all that bad. A transformer is just a laminated iron alloy core with a couple coils of wire on it. It's not frequency specific, it's just that it can handle less power at lower frequencies. If a transformer is rated for 500 Watts at 60 Hz, it'll be fine at 50 Hz if you keep it under a lower limit, maybe 400 Watts. Maybe somebody will look up the formulas and give us the exact number.

The OP is proposing to run a 20 Watt load on a 500 Watt transformer, which will be no problem at all. I did that when I took a PC to Moscow circa 1990.


-- J.S.

[Linked Image] [Linked Image]

Knabe Grand # 10927
Yamaha CP33
Kawai FS690
Re: Moving an MP11SE [Re: JohnSprung] #2818527 02/21/19 06:16 PM
Joined: Jul 2014
Posts: 1,886
JoeT Offline
1000 Post Club Member
Offline
1000 Post Club Member
Joined: Jul 2014
Posts: 1,886
Originally Posted by JohnSprung
The OP is proposing to run a 20 Watt load on a 500 Watt transformer

Where do you see a 500 W transformer? There for sure isn't one inside a MP11SE. You know how big those are?

Quote
I did that when I took a PC to Moscow circa 1990.

PCs have switching power supplies, they don't care at all about voltage or frequency.


Yamaha P-515 | Kawai ES100 | Steinberg UR22 | Sony MDR-7506
Re: Moving an MP11SE [Re: JoeT] #2818740 02/22/19 09:21 AM
Joined: Jun 2013
Posts: 365
M
Marcos Daniel Offline
Full Member
Offline
Full Member
M
Joined: Jun 2013
Posts: 365
Originally Posted by JoeT
Originally Posted by Marcos Daniel
Since the manufacturer puts the jumper there, of course they must have taken into account the AC frequency

There is nothing to "account" for. A transformer like the one you see on the bottom is either made for 50 Hz or 60 Hz (or for 20 kHz like the small ones in switching PSUs).

It takes in whatever you feed it with (it has not other choice, it's a transformer after all, not a power line diagnose system), but at the wrong frequency it will simply produce excess heat and fail at some point. At the wrong voltage, it will simply output a different voltage (and fry whatever is behind it). Voltage can be corrected by simple means (another transformer in front of it or different tap), but if the transformer runs at (wrong) mains frequency, there is nothing you can do about it, except for replacing it.


At lower frequency, there is more magnetic flux, for the same volts less turns of wire. I don't want to get in a off topic discussion but the calculus is quite simple, and if the manufacturer put those jumpers to select between 110 and 220V, they can be used. In fact there are many electric devices with a 220-240V,50Hz / 110-120V,60Hz external switch.


Pianoteq / Kawai CL 35 & MP11 / Old 1920's Upright Zimmerman
Re: Moving an MP11SE [Re: jackifus] #2818771 02/22/19 10:23 AM
Joined: Sep 2009
Posts: 9,900
MacMacMac Offline
9000 Post Club Member
Offline
9000 Post Club Member
Joined: Sep 2009
Posts: 9,900
A tempest in a teapot. smile

Joe ... they're talking about an EXTERNAL transformer, presumably rated at 500 W. Not the piano's internal transformer.
That's this one: https://www.amazon.com/Seven-Star-SF500-Automatic-Transformer/dp/B001TPZ294?ref_=fsclp_pl_dp_14

But I wouldn't use it! In the picture the unit is scarcely bigger than the power plug.
So it's not a transformer at all. It's just a modified lamp dimmer circuit.
It's a piece of crud. I might trust it to power a light bulb, but not my piano.

John/Marcos ... yes, at 50 Hz a transformer will run warmer than at 60 Hz.
But if the piano has jumper settings for 120 VAC/60 Hz and 240 VAC/50 Hz, then the design has taken the ratings into consideration. Just exactly as you've said.

Re: Moving an MP11SE [Re: JoeT] #2818776 02/22/19 10:32 AM
Joined: Aug 2011
Posts: 6,262
J
JohnSprung Offline
Unobtanium Subscriber
6000 Post Club Member
Offline
Unobtanium Subscriber
6000 Post Club Member
J
Joined: Aug 2011
Posts: 6,262
Originally Posted by JoeT
Originally Posted by JohnSprung
The OP is proposing to run a 20 Watt load on a 500 Watt transformer

Where do you see a 500 W transformer? There for sure isn't one inside a MP11SE. You know how big those are?


The 500 Watt external transformer is in the Amazon link. The OP proposes to buy one for about $40 U.S. and use it between the mains in Poland and the NEMA cord going to the keyboard. That sort of application is the reason Amazon sells such transformers. Some clone PC's back in 1990 had transformer supplies, they worked on the step down transformer with no problem.


-- J.S.

[Linked Image] [Linked Image]

Knabe Grand # 10927
Yamaha CP33
Kawai FS690
Re: Moving an MP11SE [Re: MacMacMac] #2818779 02/22/19 10:39 AM
Joined: Aug 2011
Posts: 6,262
J
JohnSprung Offline
Unobtanium Subscriber
6000 Post Club Member
Offline
Unobtanium Subscriber
6000 Post Club Member
J
Joined: Aug 2011
Posts: 6,262
Originally Posted by MacMacMac

But I wouldn't use it! In the picture the unit is scarcely bigger than the power plug.
So it's not a transformer at all. It's just a modified lamp dimmer circuit.
It's a piece of crud. I might trust it to power a light bulb, but not my piano.


The text says it converts both up and down. So it has to be a transformer, not a half wave diode rectifier, which can only be used as a down converter. I agree that the diode type isn't good for anything but resistive loads.





-- J.S.

[Linked Image] [Linked Image]

Knabe Grand # 10927
Yamaha CP33
Kawai FS690
Re: Moving an MP11SE [Re: jackifus] #2818793 02/22/19 11:09 AM
Joined: Sep 2009
Posts: 9,900
MacMacMac Offline
9000 Post Club Member
Offline
9000 Post Club Member
Joined: Sep 2009
Posts: 9,900
Good point ... but I've never heard of a 500 W transformer in that tiny size!

Perhaps it's an inverter? If so ... I would not want one feeding my piano. That's as much a power-line noise generator as it is a power supply.

Re: Moving an MP11SE [Re: MacMacMac] #2818806 02/22/19 11:30 AM
Joined: Aug 2011
Posts: 6,262
J
JohnSprung Offline
Unobtanium Subscriber
6000 Post Club Member
Offline
Unobtanium Subscriber
6000 Post Club Member
J
Joined: Aug 2011
Posts: 6,262
Originally Posted by MacMacMac
Good point ... but I've never heard of a 500 W transformer in that tiny size!

Perhaps it's an inverter? If so ... I would not want one feeding my piano. That's as much a power-line noise generator as it is a power supply.


It says 8.5 x 3 x 3.5 inches, so it may just be the picture that's the problem. Here's a 500 Watt that has the reassuring look of a real transformer, and for half the price:

https://www.220-electronics.com/500-watt-voltage-converter-step-down.html

edit: I think you're right about the Amazon unit. It only weighs one pound vs. seven for the real transformer, so an inverter is probably right.



Last edited by JohnSprung; 02/22/19 11:32 AM.

-- J.S.

[Linked Image] [Linked Image]

Knabe Grand # 10927
Yamaha CP33
Kawai FS690
Re: Moving an MP11SE [Re: jackifus] #2818811 02/22/19 11:40 AM
Joined: Aug 2016
Posts: 3,809
G
Gombessa Offline
3000 Post Club Member
Offline
3000 Post Club Member
G
Joined: Aug 2016
Posts: 3,809
In case it's helpful, here's an open pic of my MP11 (non-SE), which has the same Bando KT-032 unit as in the MP10:

[Linked Image]

I actually contacted Bando to get more information on this unit, but they were unable/unwilling to send to to me, as it's an OEM unit.

As an aside, this transformer seems to be the only part that would prevent the MP11SE from having a GF2 action rather than GF1 installed smile


Yamaha P-85, P-105, CP50, Kawai MP11 || Kawai NV-10
Page 2 of 2 1 2

Moderated by  Piano World 

ad
Rob Mullins Holiday Album
Rob Mullins Holiday Album

Rob is an amazing jazz pianist in LA,a composer, and a friend of mine.
Frank B. / Piano World
Shop our Store for Music Lovers!
Christmas Ornaments Music Theme
(ad)
Pianoteq
PianoTeq Bechstein
(ad)
Faust Harrison Pianos
Faust Harrison 100+ Steinway pianos
New Topics - Multiple Forums
A funny thing happened on the way to ASIO
by MacMacMac - 12/12/19 09:31 PM
books for learning harmony?
by Álvaro - 12/12/19 04:48 PM
Adult beginner - digital piano recommendation
by finch42 - 12/12/19 03:22 PM
Demos of CVP 809
by tangothomas - 12/12/19 02:10 PM
My latest solo piano piece. Would love feedback!
by OscoBosco - 12/12/19 02:03 PM
What's Hot!!
Our August Newsletter is Out!
------------------
Mason & Hamlin Piano Factory Tour!

-------------------
Posting Pictures on the Forums
-------------------
Forums RULES & HELP
-------------------
ADVERTISE on Piano World
Forum Statistics
Forums41
Topics195,628
Posts2,901,098
Members95,223
Most Online15,252
Mar 21st, 2010
Please Support Our Advertisers


Faust Harrison 100+ Steinways

Dampp Chaser Piano Life Saver

 Best of Piano Buyer

PianoTeq Bechstein
Visit our online store for gifts for music lovers


 
Help keep the forums up and running with a donation, any amount is appreciated!
Or by becoming a Subscribing member! Thank-you.
Donate   Subscribe
 
Our Piano Related Classified Ads
| Dealers | Tuners | Lessons | Movers | Restorations | Pianos For Sale | Sell Your Piano |

Advertise on Piano World
| Subscribe | Piano World | PianoSupplies.com | Advertise on Piano World |
| |Contact | Privacy | Legal | About Us | Site Map | Free Newsletter |


copyright 1997 - 2019 Piano World ® all rights reserved
No part of this site may be reproduced without prior written permission
Powered by UBB.threads™ PHP Forum Software 7.7.3