Synth-DIY Yahoo! Groups Archives

MX100II POWER SUPPLY ISSUE

2016-10-30 by N9544C

Greetings to all.  While listening to my MX100II, the piano suddenly went totally dead.  I thought I lost house power!  I have been maintaining my Disklavier electronics (floppy drive, display) while my local tuner maintains the acoustic portion as I have a background in electronics, have all the service literature for my model, proper test equipment, etc.


It is definitely a power supply issue as ALL outputs are 0V with the main power relay closing normally and all fuses are good!  Of course this would happen on a Saturday when Yamaha service is closed!


So before I break out my scope and start trouble shooting, have any of you any prior experience with this power supply or know of known issues?  I did read something about the 20V regulator being operated outside of its rating and shutting down and I will check that today.  Anything else?


Bill B, any first hand experience with this?


Thanks in advance,


Regards,


Mike


Sent from my iPad

Re: [disklavier] MX100II POWER SUPPLY ISSUE

2016-10-30 by Bill Brandom

Hi Mike,


Sorry to hear about your power supply problems! Mike, other than ordering replacement power supplies, I do not have specific information that can help you.


Give Yamaha Piano Service a call tomorrow at 714-522-9894 and ask for Martin Arroyo. Martin is a great electronics technician that will be able to help you with this.


Sorry I can't be much more help with this!


Bill

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-----Original Message-----
From: N9544C n9544c@... [disklavier] <disklavier@yahoogroups.com>
To: disklavier <disklavier@yahoogroups.com>
Sent: Sun, Oct 30, 2016 6:01 am
Subject: [disklavier] MX100II POWER SUPPLY ISSUE

Greetings to all.  While listening to my MX100II, the piano suddenly went totally dead.  I thought I lost house power!  I have been maintaining my Disklavier electronics (floppy drive, display) while my local tuner maintains the acoustic portion as I have a background in electronics, have all the service literature for my model, proper test equipment, etc.  

It is definitely a power supply issue as ALL outputs are 0V with the main power relay closing normally and all fuses are good!  Of course this would happen on a Saturday when Yamaha service is closed!  

So before I break out my scope and start trouble shooting, have any of you any prior experience with this power supply or know of known issues?  I did read something about the 20V regulator being operated outside of its rating and shutting down and I will check that today.  Anything else?

Bill B, any first hand experience with this?

Thanks in advance,

Regards,

Mike

Sent from my iPad

Re: MX100II POWER SUPPLY ISSUE

2016-11-01 by tnmshd@...

For your infomation.

power supply start up routin.

main switch on

controller switch on

AC power relay1 on

pon+ goes to low

drive power relay 2 on

drive power voltage out(DC100V)

connector pin number

connector A

1 +20v Led power

2 .3 +8v system power

4.5.6 Gnd

7 pon+

8 pon-

9 power switch -

10 power switch +

conector B

1.2.3 +HV DC100V drive power( caution!! high voltage.]

4 NC

6.7.8 GND

check all capacitors. liquid leak and pattern prevention.

power supply unit is end of supply.