a couple of points.
i agree that the time it takes to drop the power supply to the point that memory is no longer held should never be more than a minute at most in any decently designed circuit. if there are large filter capacitors they should have bleed resistors across them to speed their drain. it is nuts to require 40 minutes to allow a cold reboot.
UPS's can provide excellent protection but only if they are of the proper type. there are basically two types current terminology is different from what i am used to (full time ans switchover) so i had to check online to see what they are now called. it seems that the two basic types are called offline and online and there are some additional sub types. an online UPS generates the AC independent of the AC line. The line is rectifiead and then inverted to AC by the UPS. This totally isolates the connected device from the line and protects against pretty much everything that can happen on the AC line if the UPS is well designed. an offline UPS merely provides protection against power interruption (with a short switching time) and also whatever spike and surge protection that might be part of the system. this does not protect against all the crap that con occur on a power line. in most places the line is pretty free of spikes both short and long term but not everywhere.
i used to have absolutely horrible power. i lost an average of $1500 worth of equipment each winter and had two fires caused by over-voltage. this was due to horrible design of the distribution system. even with serious surge protection devices there was no way to protect against what PG&E gave me. once they fixed the distribution system (this probably cost them hundreds of thousands of dollars which is probably why they avoided it until the PUC got heavily on their case) there have been no problem that my commercial surge protection could not handle.
most people do not need the protection of an online UPS but compared to the cost of a Disklavier the purchase might be justified.
a cheaper alternative is to get a very good surge protector. when i was having horrible power i bought both a commercial whole house MOV type surge protector which cost something like $2000 retail and also surge protectors for all valuable connected devices. after a lot of research i found what i thought was the best. this was made by panamax but only some of their products met my demands. at that time they referred to their best units as "protect or disconnect". these units have a relay that must be held on by line power and will drop out if line voltage does not meet specifications. both low and high voltage will cause the relay to drop out ans isolate the load from the line. there are also MOV surge suppressors in the unit that can handle short duration transients suck as spikes and other noise filtering components.
the problem with MOVs alone is that they are limited in the amount of energy they can dissipate and also that there is no way to know what their capacity may be. they are degraded over time when subjected to over-voltage. in the panamax "protect or disconnect" devices, the MOVs are after the relay so they are protected from degredation more than in other devices.
Best regards, Spencer Chase
67550 Bell Springs Rd.
Garberville, CA 95542 Postal service only.
Laytonville, CA 95454 UPS only.
Spencer@...
Spencer@...
Spencer@...
http://www.spencerserolls.com
http://www.poodlex.com
(425) 791-0309
(707) 223-8212
67550 Bell Springs Rd.
Garberville, CA 95542 Postal service only.
Laytonville, CA 95454 UPS only.
Spencer@...
Spencer@...
Spencer@...
http://www.spencerserolls.com
http://www.poodlex.com
(425) 791-0309
(707) 223-8212
------ Original Message ------
From: "Horatio Kemeny hkemeny@... [disklavier]" <disklavier@yahoogroups.com>
Sent: 4/26/2019 4:16:17 PM
Subject: Re: [disklavier] Re: Do not play Acoustic keys MARK IV D- Help me find a service manual
Just to clarify a bit of reality here… the circuitry of all of these pianos is relatively conventional. There are no magic secret batteries or bits of memory that take a long time to drain or whatever… and suggestions that it’s needed to unplug the piano for anything longer than 30 seconds are simply wrong, as far as rebooting the electronics. The only thing in these pianos holding a charge of any significance are the capacitors, and even the biggest and baddest of those, in these pianos, are fully drained after 15 seconds. Thirty, if you want to be super-duper sure. But 40 minutes? An hour? Makes no difference.
That being said, if you’re finding that your piano works best (and reliably) after unplugging it for an hour or more, then you have indeed identified a problem, but it’s not one that's resolved by rebooting.The issue in that case is overheating… and unplugging it for an hour or more simply gives it a chance to cool down.The two most common issues that cause overheating are a cooling-fan failures and the accumulation of dust. These pianos are wonderfully designed not to need cooling fans (even the silent ones are noisy, and when they fail they’re awfully noisy), and therefore, the only issue might be restricted airflow. These M4s have two main components that are relevant, the power supply and the I/O board. They’re the ones enclosed in those metal boxes, and if you crawl under the piano on your back, you’ll see those metal boxes and how full of holes they are. What’s lost without a fan is gained by having as many holes as possible, to promote cooling from ambient airflow… and it works very well, provided those holes aren’t covered In dust.Blow compressed air, suck it with a (not too strong) vacuum, whatever. If you’re finding that your piano gets unhappy after being on for a while, and a long-term reboot seems to resolve the issue, this is quite likely what’s going on.To answer a couple of other questions that have appeared in this thread, it is indeed important to fully unplug the piano. There’s a lot going on in “stand-by” mode. Unplugging the main guarantees that nothing anywhere is getting any power, and indeed, it’s the primary (and only) source of power to the piano. Various components are powered from the power supply (you can see the distribution of that power when you look at it, as per two paragraphs above), but it’s all fed from one single plug.With respect to power spikes… a UPS/line-conditioner is a really good idea with an expensive and somewhat-sensitive instrument like this. It won’t prevent a power supply from failing and frying your I/O board (rare, but it happened to someone and I’ve had it happen to a computer as well — just rotten luck) but it will prevent the sort of spikes that could cause problems.While lightning strikes are unlikely, far likelier are power outages, and corresponding surges when power is restored. Those can cause serious issues… and a UPS addresses both. And also provides even and reliable electricity.…..HKOn Apr 26, 2019, at 11:01 AM, master-12l@... [disklavier] <disklavier@yahoogroups.com> wrote:Good day:)Thanks for the answer.Really need to turn off so long? I turned off but a maximum of a minute.It is necessary to switch off completely the unit where the power is distributed and where does everything else already feed from?