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Barindra... I'm curious! Why do you accept the two neutrals remaining connected via the Ground/earth link, as normal? Phil

Shirley... unless otherwise required by the manufacturer, and your facility conforms to NFPA regulations, the FD-fan should be started first for both the Cold- and Hot-Start. This is to insure an open-flow path from the FD-fan inlet through the stack, thus preventing Furnace Implosion...

Doobs... hopefully you are immune from future litigation should there be a mishap. Phil

Doobs... correction to my earlier post: b) If the neutrals of both sources are grounded then there is a division of current-flow inversely proportional to the impedance between the each source and fault location.

Doobs you have an interesting sense of humor! I wish you had mentioned the relaying problem first. Replying to your comments: a) When a ground-fault occurs, and the neutral of one source is grounded, then the fault-current's return path will be to that source, regardless of how circuitous...

Sudamadhav... the flux change you noted are shown in my white-paper, "The Physics of... Armature Reaction." Regards, Phil Corso

Doobs... after further review I find the existing arrangement will not be exposed to the Neutral Displacement phenomenon because it insures that one of the two sources, i.e., the Gen'r or Utility source is "always" connected to the load's NEUTRAL-BUS. However, there is a problem related...

Doobs... further to my earlier post, details can be found in the Control.Com Archives, specifically: o http://www.control.com/thread/1026242921 Phil

Doobs... thank you for your prompt reply. And, Yes, the sketch shows that with both sources closed, the neutral (to the load) is isolated. This is the classic case of "Neutral Displacement". That is, Phase-to-Centroid (point at which Y-loads are connected) will vary for each phase. The...

V.Willet... further to my earlier post: 5) Is motor Wye-connected or Delta-connected?

VWillet The AUF (Voltage-Unbalance-Factor) is about 2% using both NEMA and IEC standards. If the problem were only related to supply voltage imbalance, then the corresponding AUF (Ampere-Unbalance-Factor) should be about 5%. Instead it is over 30%! The readings are indicative of a motor...

Doobs... are you referring to a situation in which an engine-driven- generator is paralleled with the utility source, via an Automatic-Transfer-Switch (ATS)? Phil Corso

Doobs... Can you provide a hand-drawn sketch or a Single-Line-Diagram detailing your system layout? Phil ([email protected])

Dobbs... Search Control.com Archive for "Neutral Interruptus". Regards, Phil Corso <b>Moderator's Note:</b> Enter the following in the search box: +"Neutral Interruptus" The quotes and + are part of the search term.

VWilley... please provide Nameplate data, application, and if this is a VFD controlled. Regards, Phil Corso

NKT... correction: Multiplier for case c) is 4. Phil

NKT... the technical reply, of course, has a number of "It Depends On" answers. So, here is a very elementary approach, depending on how the 12Vdc is derived: a) Half-wave rectification (1 diode) but a lot of ripple effect. b) Full-wave rectification (2 diodes) but less ripple effect...

Sivaji... as long as the unused-cable is grounded at both ends an air-core transformer is constructed. Thus, if any of the other conductors carry AC, a current will be induced in the grounded coil. I suggest you search the Control.Com Archive for: o...

Troy... cost comparison is the best way to convince most people, especially if they're paying the tab. 1) I'm familiar with a 1998 comparison study that showed a 480V would save $40/kVA demand over 208V. 2) Although the 208V system has been around a long time, today, the 480V is preferred...

Instju... how large is the steam-drum? Regards, Phil Corso