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SGS, > Why there is always a consistent voltage of 11 kV in most of the generators up to 100 MW? Would it surprise you to know that in many parts of the world where 60 Hz generators are used the most common generator terminal voltage is 13.8 KV? The reason these voltages are common are...

SGS, These "torque angles" are the result of loading a synchronous generator and it's prime mover--NOT the reason for loading. It's very important to understand that these are just mathematician's and physicist's ways of explaining and modeling and predicting what's happening in the...

Saud Aslam, Carbon brushes are the best for transmitting high current from an exciter output to the rotating slip rings connected to the rotating generator field leads. Brushless exciters have their place, but are typically not used on machines above approximately 100 MW. Why? I'm not...

TC, Thanks for the feedback! As you said, what makes threads really meaningful is being able to see what worked and what didn't and how the problem was solved. That's one of the really great things about the people using control.com--that they usually write back to let us know how things turn...

Roman69, The question in the thread is, "What does these levels (Var min and Var max) effect for?" And, there is indication that Var/Pf mode is off (not used). So, <b>Var</b> min and <b>Var</b> max would likely not have any effect on the operation of the gensets as they would be setting...

JG, Actually, there is virtually no difference in exhaust spread trip logic with one little exception: F-class turbines look primarily for hot spots while non-F-class turbines look, primarily, for cold spots. For non-F-class GE heavy duty gas turbines, most combustion problems are the...

Marcin2706, > The second problem is DLN – I Combustion system. In DLN I system the exhaust temperature TTXM is higher than > for unit with conventional combustion system. This statement I hope is true. Actually, if you look at the Base Load exhaust temperature of a conventional...

Ann, > Is this true ? + 125 V DC and - 125 V DC? > Not + 62.5 V DC and - 62.5 V DC ? > Please correct me if I am wrong. The reference is to the positive- and negative legs of the nominal 125 VDC source, which can be higher or lower than +62.5 VDC and -62.5 VDC depending on the number...

Saudaslam, DC isn't just something that comes from an outlet in the wall; it has to be "produced" and that implies some means of control. That is what the exciter does: it controls the production of DC from an AC source. By the way, exciters are also called "AVRs" by many people (Automatic...

Damien PELLISON, If you're referring to the velocity ("seismic") vibration pick-ups typically used with a Mark VI there is no filtering possibility if the standard vibration block is used. Filtering is typically only used with accelerometer or sometimes proximity probes. If the...

Neo, As you wish. But, if you haven't discovered this already learning background information about anything helps one to understand how it works, why it works the way it does, and how to troubleshoot it when it doesn't work. Just knowing the thing doesn't do that. The journey we are on could...

Anyone can download the .pdf file using this URL: http://www.ansaldothomassen.com/upload/file/quick/CRV_lr.pdf There is a little more information on the AnsaldoThomassen website. This is a purchased after-market add-on, which requires tubing modifications (hopefully not modifications...

aim, > What about the feedback from the speed pick-up 77FD1 and 77FD2 on the flow divider? If you're asking if the flow divider speed pick-up feedback affects servo-valve calibration, it doesn't. Flow divider speed pick-up feedback is scaled from Hz/gpm to lbm/sec (lbs. mass per...

Marcin2706, I didn't find a question in this latest post.... In either type of combustor the only time firing temperature is controlled is when the unit is operating with the IGVs full open and on CPD- or CPR-biased exhaust temperature control ("Base, Peak, or Peak Reserve). TTRX is...

TC, I'm really not clear on the problem(s).... Have you verified the polarity of the current being applied to each coil by <R>,<S> &<T>, individually? Look at the IGV P&ID but if 20TV-1 is de-energized then the IGV Dump Valve should <>NOT</b> allow hydraulic oil through the servo to the...

G.Rajesh, You make an excellent point: If it was possible to stroke the IGVs manually, then there should have been no problem with the Speedtronic moving the IGVs during operation. The Shotgun Approach to troubleshooting (as was done in this case) does not lend itself to understanding why...

HAR/technical, 2) Yes; it's correct that if someone copies files from a running project that all files will not be copied because files that are open and locked cannot be copied. To copy CIMPLICITY project files <b>(which is >>NOT<< recommended, by the way)</b> one should stop the running...

HAR/technical, If all the CIMPLICITY project files were marked as read only that would mean it's very likely someone "restored" from a CD or DVD. And that means we don't know everything that's been done--and everything that's not been done. Which makes it very difficult to offer suggestions...

Neo, I would answer no; our L4 journey is not complete, as we didn't finish all of the L4T rungs (at least I don't think we did). As for what's next, well, that's up to you. What do you want to discuss next? We've talked about inversion masking; drop-out-to-run; signal naming. Other topics...

TC, I'm surprised there is a significant difference between the voltages at the TBQA and the voltages displayed on the DIAGC display. The only way I could explain large differences (tenths of a volt or more) would be that a non-True AC RMS voltmeter isn't being used, or the voltmeter needs...