Thanks again. What we are trying to do is to monitor the operation of our generator relative to its capability curve. If the operating point is within the curve, nothing further is required. If the operating point is outside the curve, the difference is recorded as well as the time it operated...
Thank you very much for the information. Is the Siemens/Westinghouse paper, Adjustment of Generator Capability Curve available? I've checked their websites and did a search but I can't find any reference to the article/paper.
Does anyone know how to draw a generator reactive capability curve as a function of the cooling air (for an air cooled machine)? The centers of the circles are fixed but the radii of the circles will vary as a function of temperature (assuming constant voltage and frequency). Both stator and...
Is is true that there is a 'Special Inspection' program accepted by the Authority Having Jurisdiction (which is not necessarily the Province or municipality). However, there are very few equipment where there no standards. While there is no such thing as an approved liquid-filled transformer...
In Alberta, it is illegal to sell or use electrical equipment are not approved by any of the approved certification agencies certified by the Standards Council of Canada. This is clearly stated in the Canadian Electrical Code and the Electrical Regulation. (I am sure other Provinces have similar...
Motor heating (stator and rotor) is caused by the I2T heating of both positive and negative sequence currents. This heating is compared with the manufacturer's thermal damage curves.
So, as a general statement, even if the motor is not fully loaded, it is possible to damage the motor depending...
What you are referring to as E standards are standards for equipment for classified areas. Remember, Canada has adopted the zone system for class I locations instead of the divisions (NFPA). Those 'E' standards are based on IEC standards and they are some changes. As far as I know, these are not...
I believe it is optional. NEMA standards do not require them, especially for 250Hp, which is is still 'small'. Even RTDs are not required, especially bearing RTDs.
I would say that good practice is to hardwire the N/C contact in series with coil. If your O/l has an available NO contact, you can still connect this to a PLC input. You can then also trip the motor via logic in addition to the hardwire NC contact.
Depends on the type of battery. Some batteries, although may have a listed life of 10 years, may fail in 3. Most would require replacement in no more than 7. Only a few will actually last 10 years or more. Or course, this also depends on the number of discharge and charge cycle, temperature...
Could be referring to partial discharges (sparks) which could be mistaken for 'flashover'. Not aware of a protective device that will protect from such discharges. Generally protective devices will respond to other failures like grounds. But the partial discharges can be measured off line or...
V-curves and capability curve will help in analyzing the performance of the machine. If the machine reactances are knowb, you could draw the capabilty curve.
