Disklavier

Good morning, everyone.

Brad, your detailed information is fascinating. Good luck with this!

I have no information to offer you except the following: I have a DC6 IIXG PRO. At one point, a mechanical issue developed with the sustain pedal solenoid and trapwork. At this point, I cannot recall how the problem developed nor over what period of time. The bottom line was this: the sustain pedal no longer moved freely.

As a pianist, I had not noticed a gradual increase in the resistance of the pedal, which leads me to suspect that my problem developed slowly over time. Upon comparison with other pianos, it was obvious that it took too much effort to move my pedal, and therefore the solenoid had to work too hard and errors resulted.

Ultimately it was necessary to make a variety of adjustments to the trap work to get things working smoothly—and I have had no problems since. My Disklavier technician took care of the matter for me.

Regards,
PianoBench


> On Jan 16, 2015, at 11:29 AM, Brad Harper bharper33@... [disklavier] <disklavier@yahoogroups.com> wrote:
> 
> 
> Update on the Piano Power Off  #15 "PWR OVER” Error on a Mark II GH1B Grand DKC100R with MU50 after about 30 Seconds of Play.  
> 
> I ran the Error History, here are the results:
> Sensor LED ON error #8 Count = 094
> Sensor Not Connected #9 Count = 085
> Piano Power Off (PWM OVER) #15 Count = 039
> 
> I removed the power supply and dis-assembled it, and ran tests on all the Output Voltages and inspected all components for signs of Overheating, Leakage, cold solder joints and Failure.  The Power supply tested out as normal, in fact looked rather New.
> 
> I replaced the incoming power cable, and power strip with a premium grade replacement.
> 
> I read all the service manuals, and studied all of the schematics, block diagrams, Error Descriptions, and Troubleshooting manuals.
> 
> The DGP1/DGA1 service manual on page 60 gives this description of the Error Under the PK-CTL Board – Protect Function:
> 
> No	Message		Condition								Contents and Countermeasures
> 
> 15	Piano Power Off	The keyboard & sustain, soft / shift pedal 	100V (120V for Grand) of power to Keyboard and pedal drive OFF.   
> 	(PWM OVER)	playback stop.  Playback function cannot	One or more key drive transistors have become too hot and the
> 					be restored until the drive transistor(s)		protect circuit has activated. ® Check the drive board
> 					has/have cooled down sufficiently and 			
> 					the power has been turned off,then 		
> 					turned back on.
> 
> The DGA1XG Service manual lists the PK-CTL Board Part Number as VU691100 for the DGH1BXG model
> The Block Diagram shows a Thermo Protect F1 on the Gate Array with inputs from Thermostats on the Drive A, B and Pedal Units.  They all look like there are in series to Ground,
> so the opening of any thermostat will signal the thermal protect to shutdown the piano.
> 
> Tomorrow, I am going to adjust the Pedal Solenoids, the Half pedal settings, the pedal linkage gaps, and put a meter on the Thermostat line to see if it opens during play.
> 
> It kinda makes sense that there maybe something wrong at the pedal unit, because it was removed during the move.  The pedal Solenoids are huge, so I can understand
> If they are creating a lot of heat on a drive transistor at 120VDC, enough to trigger a thermostat overheat.
> 
> Schematics have been very helpful as well as component adjustment info and error information.
> 
> Will let you know of the progress…
>  
> 
> 
> 
> 
> From: "Brad Harper bharper33@... <mailto:bharper33@...> [disklavier]" <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Reply-To: <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Date: Tuesday, December 30, 2014 at 5:13 PM
> To: <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Subject: Re: [disklavier] Service Manual and Schematics for MarkII DKC100R
> 
>  
> 
> Hi Carol,
> 
> I did disconnect that harness, and reconnected it, and it was loose when I first checked it.  I also did a check that spencer suggested, which is to record a run of the keys, and then playback only that to see if it stops at a certain key.  The problem is now it has progressed to not playing anything.
> 
> Brad…
> 
> From: "Carol Beigel carol@... <mailto:carol@...> [disklavier]" <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Reply-To: <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Date: Tuesday, December 30, 2014 at 4:47 PM
> To: <disklavier@yahoogroups.com <mailto:disklavier@yahoogroups.com>>
> Subject: Re: [disklavier] Service Manual and Schematics for MarkII DKC100R
> 
> 
> 
>