Important! they're about to mess w/ our wall power !UPDATE!

[???????]

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[fossiltooth]

Thanks man! I sent a friendly email to those knuckleheads too. Let's see what we can do.

[???????]

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[kslight]

Done. I have a feeling that whoever proposed this cost reducing measure is nothing more than a short sighted bean counter. I find it difficult to believe that they will go through with this, I think it will affect nearly every device in some shape or form.



Someone that is more knowledgeable please chime in...say they did go through with this...to what extent would a power conditioner influence this?

[Anthony Caruso]

Just to play Devil's asshole here...

In other words, it was estimated that approximately 97% were of such a magnitude that if the Time Error Correction had not been in effect, the exceedance of the low FTL would not have occurred.

It seems like they're saying that because of the Time Error Correction, the low Frequency Trigger Limit (FTL above, or 59.95 Hz) was exceeded more than it would have if there was no error correction.

Yeah, maybe someone with expert knowledge can interpret this page http://www.nerc.com/page.php?cid=6|386 better than I but I think that's what they're getting at. (sorry that link formatting is effed, don't know why, copy and past will work)

[drumsound]

I just emailed as well. Thanks for pointing this out.

[ofajen]

Thanks for posting this. I read the NERC webinar referred to in the Yahoo article. They are going to stop manual time corrections as of July 14, 2011 on a trial basis and will continue it unless they hear of reliability concerns or complaints of commercial impacts.

This change will have two main effects. The up side is that real frequency accuracy will actually improve (i.e. the RMS deviation from exactly 60 Hz will get SMALLER, because the target frequency will ALWAYS be 60 Hz. The down side will be that electric system time will no longer be official time (or kept within, say, 10 seconds of official time.)

Power conditioners won't help on time error, but moving to Texas or Quebec will, based on historical frequency performance. Also, the comment about alternative energy is relevant but reversed: part of the reason for making the change is to keep the target at exactly 60 Hz, which helps maintain reliability and frequency within range as we rely more and more on alternative sources with a more variable duty cycle.

Cheers,

Otto

[???????]

I've been doing some more reading about this myself. There is some evidence that cycle frequency could actually improve-- something about the error correction being done all at once, in the middle of the night, where they speed up the cycle for a bit so it can "catch up" to the required number of cycles per day.

It's hard to tell what's fact, what's fiction, what's straight, what's spin, etc. I guess we'll just have to wait and see.

[donny]

but i like to use my tape machines in the middle of the night !

[???????]

but i like to use my tape machines in the middle of the night !

Then there's some evidence your situation might actually improve.

Bob Ohlsson, on another forum (on a similar thread I started over there) said this:

've been reading a bit more about this which suggests it's a non-problem that is being blown up as sensationalism for some reason. They are NOT proposing any change to either the nominal 60 Hz frequency, or the limits on frequency excursions. They will simply stop counting cycles, and stop deliberately forcing the grid off frequency each day to correct the cycle count.

[lacquer_monkey]

I think you will find that all pro and many consumer reel to reel machines use DC servo motors controlled by a phase locked loop to control the speed (capstan). This is what allows a tape machine to chase time code or have the transport speed varied by the ubiquitous vari-speed control that virtually all of them have. The AC pretty much just goes to the power supply where it is converted to DC of various voltages that feed all the various systems in the tape machine.

[ofajen]

I think you will find that all pro and many consumer reel to reel machines use DC servo motors controlled by a phase locked loop to control the speed (capstan).

Generally true for later machines, but early machines used AC sync motors. All the Ampexes up until the AG-440 series were AC sync. The original AG-440 had AC sync motors. DC motors became an option in the AG-440B series. DC motors were standard equipment in the C version, though AC sync motors were still an option. 3M machines used AC sync motors for M-23 and M-64/M-56 series and switched to DC motors for the M-79.

The point is well taken, however, that cycle frequency accuracy is only a potential issue for older machines with sync motors.

Connecting back to the original topic, NERC expects that cycle frequency accuracy will improve, since most of the out-of-range frequency deviations are associated with the change in target frequency required by the time error corrections.

BTW, the .05 HZ frequency deviation trigger corresponds to slightly more than one cent tuning deviation with an AC sync motor transport, so it's pretty much not an issue. The NERC data show that this amount of deviation only occurs an average of two minutes per day.

Cheers,

Otto

[donny]

ah, i see ... business as usual !

[snatchman]

but i like to use my tape machines in the middle of the night !

Hey donny.. So I guess it means as you use your tape machine in the middle of the night, it'll improve your 2" machine running at 30 ips will all of a sudden, take off like a bat out of hell to 60 ips and you'll get one song out of a roll of 2" tape..!... ...

[???????]

Good to hear from multiple sources that this is really much ado about nothing. Sorry if I started a panic.