thank you byrdj and ScottyUK
Actually The generator is in idle / stop condition when it happens.No one check the seal oil system until we found that our Main oil tank (for turbin lube oil) level had decreased for about 1 meter and we search all the systems and found all the hydrogen drain line...
We have a huge problem in our 300 MW generator. The generator seal oil ingress in a huge amount into the generator. so almost all the rotor winding and lower part of stator submerged in seal oil. we have drain all the oil through the hydrogen drain system.
Is anybody ever heard a situation like...
What is the definition of over sized motor? I have checked the operation condition, running current is about 77% of I rating. Can we say it is over sized?
Hi Waross,
Sorry for my lack of knowledge on electrical power system, what do you mean by "relays and/or contactors are not dropping out" Is It unproper to set under voltage as low as 75% ? because I later found that our Medium Voltage Motor even set on lower value at 54% with 9s time delay.
Hi All
we have fuel oil supply pump motor rated 90 kW to supply fuel to main boiler. this motor is supplied from grid, and unfortunately the grid is often faulted by lightning strike. after the fault happened, the voltage is decrease for a long time and recover again.But our motor have already...
Hi.
Is there any paper or study describe relationship between operation mode and failure rate of a power transformer. example if the transformer often energize on load (load side CB close) it will raise the probability of transformer fault due to higher inrush current if compare to energizing...
Yes it is a radial system. sorry for my english but my point is, Standard Operating Procedure always says that we have to energize (Close CB) on Primary of transformer ( supply side) first then the secondary (load side). is there any standard or recommended practice related to this point. Or we...
Is there any standard or best practices stated that we must first energize the upstream system then the downstream system.
example : for a transformer (150kV / 6 kV) feed a 6 kV Busbar. The busbar feed 3 Dry transformers (6kV/400V). We must first energize the 150kV Transformer, then busbar, and...
Sorry if my english a little bit confusing to all, my point is just like ScottyUK says. The main rules for energizing a load is from upstream to down stream ( power source to the load). I wonder if there is any standard (e.g IEEE, IEC) that stated that if the power on the upstream off because...
We Have two Station Service Transformer (SST) to supply our 6,3 kV Station Board A&B on a Coal fired Power Plant. The SST rating is 150 / 6,3 kV and primary side (150kV) supplied from the 150 kV transmission line through GIS (Gas Insulated Switchgear). There was a black out on the system so the...
I'm not sure about the neutral CT wiring, is it correct or not. but the CT commisioning already carry out and the result is good. I'm confuse how both of our Station service transformer trip at the same time because they attached at different diameter on GIS 150 kV
Is there any Possibilities Restricted Earth Fault Protection of Transformer active because of unbalance load,Fault on the transmission line, or other cause besides ground fault on HV side?? I'm curious because recently two of our Station Service Transformer trip simmultaneously, and both are...
thanks a lot for your explanation smallgreek
I'm pretty sure that the name plate say 110/√3 / 110/3
that's what confuse me, is it the secondary voltage too? but why 110 / 3 instead of 110 / √3
it is uncommon value of secondary voltage.
I couldn't find the manual book, and by the way it is...
My Company wants to buy MCSA (Motor Current Signature Analysis) for our PdM (Predictive Maintenance)System. I'm really a beginner about this MCSA, I only know that it can detect any malfunction inside a motor like broken rotor, eccentricity air gap etc. Basic on your experience, what's the...
Waross : for motor larger than 2 MW (like ID Fan), it also provided with differential protection, the motor relay management is also provided with voltage protection like under/over voltage. what do you think?
electricpete : I have learn about this protection scheme, it is provide with zero...
I work on a Coal fired power plant project now. We use 6 kV system for the large motor like ID Fan, FD Fan, etc. We use relay management system from China. this protection system only use 2 Current Transformer (CT)for the protection (phase a & c). none in phase b. do you think it has negative...
