My company has plans to repurpose an existing 4 kV, 700 hp motor presently driving a 700 hp centrifugal water pump. The existing pump is being replaced with a smaller pump that requires only about 300 hp. What changes in the motor's existing protective relay settings, if any, would be...
Would anyone happen to know the equation for the tripping time of a North American Class 20 thermal overload relay? If so would you mind enlightening me?
Gentlemen,
An AE firm came up with the settings for a Siemens WL breaker with an ETU trip unit. I think they used SKM software to get the numbers.
This involves a recently installed Goulds reclaim water pump driven by a Reliance 460 V, 250 hp motor. FLA=272A. LRA=1825A.
Trip Unit Settings...
According to the literature of one manufacturer their capacitance-based level instrument using RF admittance techniques is able to distinguish between the capacitive RF current through the medium's level as well as both the resistive and capacitive components of the RF current through the...
Folks,
My extensive Googling has not borne any fruit in regard to metric metal screws. There is such a thing as a metric metal screw, is there not? Do these things use the same thread pitch and diameter as standard metric machine screws? Where could I find some specs for these fasteners?
Recently at one of our sister plants an employee was burned when an arc occurred as he was inserting the fuses for a DC motor operated valve. What caused the arc is still under investigation.
However one of the persons who is involved with the investigation issued a proclamation which blamed...
Folks,
We started for the first time recently an 18000 hp induction motor: 13.8kV, 900 rpm. The Multilin 469 relay took it out immediately on short circuit. In round numbers phase C current was about 8000 amps, while phases A and B currents were the same at 4500 amps or so. Normal starting...
Folks,
After nearly 34 years of a power generating station career I retired about a year and a half ago. Now my former employer would like to hire me through a third party to prepare and present specialized training to key operating personnel in several power plants. The subject matter would...
