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Hi, Reverse power occurs when the energy flow-rate into the prime mover is not sufficient to maintain rated speed while the generator breaker remains closed. In this case the generator actually becomes a motor, drawing amperes from the grid in order to maintain rate speed. In effect this...

Shaheed, Seems you were sleeping while reading the above posts. The reactive capability curve for your generator defines the limits of operation. The specification sheets for your PTs define the maximum voltages and the saturation voltages they can withstand. There's just too much...

I am unfamiliar with TTHT, so can't help with that. The liquid fuel nozzles should be purged with air whenever the unit is running on gas fuel. Having said that, there have been documented cases of liquid fuel check valves leaking backwards while running on gas fuel, allowing hot...

Saif, Welcome. When considering AC power generation, there is the generator and its prime mover. The prime mover supplies torque to the generator, which converts the torque to amperes (which are transmitted via wires to motors and other devices which convert the amperes into torque or...

Amosiss, Presuming the Torque Adjustor limit switches are adjusted and working correctly during a normal START, purging draws (or should draw) approx. 150-160% of motor nameplate during purging, and when the purge time is complete the unit should coast down to firing speed (about 10-12%) and...

Surya, You didn't say what kind of job GE has offered you. Field service? "Office" engineer? It seems to be "instrumentation", but you said your background is mostly operations and mechanical. In some cases, the best instrumentation (controls) engineers I worked with had...

GTT, If all the inputs to the combustion reference temperature algorithm are working correctly, there's probably very little difference between actual firing temperature and the combustion temperature reference. I believe that GE stopped calling TTRF/TTRF1 the "Firing Temperature...

ABDI, Primary flame detectors (I presume you are talking about primary combustion zone flame detectors--you weren't specific...) can only be mounted on combustion cans with mounts and that have combustion liners and flow sleeves with the appropriate sight "tube" holes through which the...

LCH, Every generator is supplied with something commonly called a "Reactive Capability Curve", sometimes called a "D-curve" (because it has a shape like a capital D). The Reactive Capability Curve defines the limits of operation for the generator--for real power (watts), lagging VArs...

RedJim, A few questions. First, how long have you been doing on-line water-washes on your Frame 6B? (I presume for a period of several years; but please be as specific as possible.) Second, how long has the unit had the DLN-I+ combustion system? (In other words, was it a DLN-I unit before...

MIKEVI, Have a look at this thread: http://www.control.com/thread/1389348883 By copy to Amosiss, this topic has been covered before on control.com. As has been written before, the Control Constant current value is not a "cast in stone" value but rather a "sanity check" to make sure the...

Roberto Benedetti, It's not necessary to have all of the synchronization equipment for operating multiple DC generators together--only for AC generators. And measuring DC is somewhat simpler than measuring AC (no PTs/CTs required). You seem intent on having multiple diesel generators...

Adrian Tomes, It most certainly is possible to automatically start a second generator to connect ("parallel" or "synchronize") to an isolated grid (sometimes called an "island" grid) when the load on the first generator increases above a certain threshold. One doesn't really start a...

Roberto Benedetti, Most of my experience is with industrial applications (MUCH larger industrial applications producing AC power). So, most of my experience is with larger, industrial (commercial) equipment (think megawatts; tens to hundreds of megawatts). What I did not understand from...

Roberto Benedetti, An OTS (Off-the-shelf) multiple engine-generator controller system--just for the controller--would probably cost about USD10,000.00. They are pretty specialized and highly user-unfriendly. For any kind of automated system (PLC-based or PMS (Power Management System)...

Roberto Benedetti, This could be automated with a control system, but there is nothing OTS ("off the shelf") to do this, with the possible exception of something the diesel generator manufacturer might make or sell. I venture that anyone selling you something that would allegedly do this...

GE Speedtronic turbine control panels used several shutdown fuel control schemes, anything from just shutting off the fuel at around 95% speed to a controlled ramping down of fuel to lower speeds. If this panel uses the latter, then something is wrong with either the fuel valves or the...

Elvin Aponte, Thanks for the feedback, and let us know about the condition of the EEPROMs you receive from GE.

>Mark IVs are older control systems, and >if one of the three 4 Master Protective >Relays is dropped out <B>AND</b> then >one liquid fuel ow divider feedback was >lost THAT could (depending on how the >sequencing was written) result in a >"Loss of Flame" trip. WOW!!! That paragraph was...

Manjunath, > 2 hour prior to machine trip one magnetic pick-up started reading value greater > than other two and at one instant all stopped working. If all flow divider feedbacks all stopped giving an output at the same time, then something appears to have caused the flow divider to stop...