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Kam, For a three-phase AC motor the formula for power consumed by the motor is: Watts = V * I * 3^0.5 * pf. (The 3^0.5 is the only way I can express "the square root of three" on this forum, which is approximately 1.732.) Most AC motor nameplates list the current drawn at rated...

Md. Nubayeed, Did you try typing "Metrix 5485C" into your preferred Internet search engine? This was the first (top-most) search result when I did: http://www.metrixvibration.com/Products.aspx?ProductUid=25 (remove any spaces inserted by the control.com forum software) The topic of...

gshan, Although I'm familiar with the Rowen model, I'm not familiar with the GAST model. To the best of my knowledge, GE still produces gas turbines--and controls--with the same speed, acceleration and exhaust temperature control. Most gas turbine manufacturers have some similar types of...

Divyang Shah, TMR or SIMPLEX Mark V? This alarm usually means there was a loss of IONET communications between <Q> and <C>. If the Mark V is a SIMPLEX, then it's going to trip. There have been TILs (Technical Information Letters) about PROM upgrades to resolve this problem. Another...

Michael Asian, What makes you believe there is a failed sensor? Because usually, there is some kind of alarm (Process or Diagnostic) which can be used to trace a failed sensor. There's not enough information here to be of help with providing you a procedure to help you identify a failed...

sagir, 1. My feelings were that the Rev. C switches might have caused some problems with the Traco power supplies, which are generally very reliable--but in this circumstance might be suspect. Have you examined the loading of the power supplies? How much is the total current requirement of...

All, It seems presumptuous to say the motor in question is a "stepper motor". Most of the speed changer motors I've seen on older mechanical steam turbine control systems (such as this seems to be) were simple DC motors, which could be reversed by simply changing the polarity of the applied...

gshan, I'm very happy to answer any questions, and provide any clarifications. I'm also glad to hear the example was useful.

Fyzal, Thanks for the update. As for what could be causing the drop in CPD, quite often when some disturbance or event like the one being experienced occurs the lost CPD is not recoverable. Once cooling and sealing air flows have been interrupted, it's likely the internal clearances of...

Shaheed, There are "alternators" and there are "alternators." Most reciprocating engines with battery-operated starting motors have a means of charging the battery when the motor is running, and these days those are called alternators, because they actually produce AC that is rectified...

gshan, Presuming the load (the number of motors, lights, computers and computer monitors) connected the grid being supplied by the three generators with their governors operating in Droop mode was stable and the grid frequency was stable and therefore the grid frequency was stable, when the...

As Bob Peterson says, in general, there is no problem with sharing the junction box for DIs and DOs. Many times they are both at the same voltage level. The real problem with signal level separation/segregation is with cables running in parallel over long distances, especially when one or...

ESKAY, You wrote, twice: >I have calibrated both SRV and GCV servos.... You did NOT calibrate the servos; you calibrated the LVDT feedback from servo-operated devices. Or, you calibrated the LVDT feedback from devices with servos. But you did NOT calibrate the servo(s). Please...

Bob Johnston brings up a very good point I hadn't considered because I'm still not clear about the problem description. During starting the ratchet is run continuously (no 3-minute wait between cycles) in an attempt to provide that little "bump" necessary to help the starting means (through the...

Peaking.Duck, Hello, and good on you for being proactive. An SFC (Static Frequency Converter) is a device that converts AC (in this case, three-phase AC) to a variable frequency output. This output is then applied to the generator stator, and is used to accelerate the machine during...

Elshaer, If I understand the description, no; it's not normal for 33HR to toggle <b>AFTER</b> the shaft has broken away from zero speed. For most Frame 5s, a "bump" from the ratchet mechanism is required to help the starting means (via the torque converter) to break the shaft away from...

ESKAY, I would like to ask two questions, please. When you removed the feeler gauges after the LVDT calibration/verification of both the SRV and GCV, and you had operated the valves a couple of times, what was the indicated position when the valve stem was fully down? Was it negative or...

ESKAY, I am very happy to hear you were successful with the LVDT calibrations, and that you were able to determine the correct jumper to move and what position to move it to for the SRV calibration. Most importantly, thanks for the feedback! "Feedback is the most important...

gshan, First of all, a governor may or may not be capable of both Isochronous and Droop Speed Control. It depends on the governor manufacturer, and if the governor is capable of both then there must be a method for switching between the two (since both governors modes cannot be active at the...

blur, GE is trying many new logic and control sequences to try to accommodate various fuels and operating conditions. It's very likely that the control logic and algorithm in use at your site is specific to the application. This is not common for most GE-design heavy duty gas turbines, though...