3-phase AC GEN - Page 2 - Airline Pilot Central Forums

#11

IluvRNP , 12-27-2009 07:30 AM

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Quote:

Originally Posted by Dougdrvr

If you couldn't get a generator on line as a new, wet behind the ears, FE and you turned to the left seat and said " Cap'n, we have a Phase Un-balance!"......... I guarantee you the response would be, "What the he11 is that?"

Perhaps some, but not all by any means.

#12

III Corps , 12-27-2009 08:45 AM

No one's home

Quote:

Originally Posted by IluvRNP

As I recall the 707 (preceded the 727) was about the same.

the 707, 727 and 737 all had similar electrical sys with 3 phase 120 volt 400 cycle gens rated at 40kVa. The new 787 is a MONSTER for electricity since many systems are now electric (gear, flaps, nosewheel steering, air conditioning/pressurization).

from the web:

Quote:
*
Electrical Power Generating and Start System (EPGSS): The EPGSS generates and controls the electrical power on the airplane. The system also provides the APU and main engine start capability, and the motor controls are multiplexed to drive the cabin air compressors and electric motor pumps. The EPGSS comprises four main engine-mounted variable frequency starter generators and two APU-mounted auxiliary starter generators. It also includes eight common motor starter controllers, six generator control units and two bus power control units. The system will produce 1.450MW of electrical power – five times the power generation capacity of the 767 and enough to power 400 homes. This will be the first time a large turbofan engine has been started electronically, and the EPGSS provides key technologies that enable the 787 to be the first "more electric" airplane.

Note, with the new systems will come a plethora of new terms, abbreviations and jargon.

Ground school instructor:"today we look at the "EPPGIZ" and its components"

#13

SomedayRJ , 12-30-2009 04:00 PM

Gets Weekends Off

Quote:

Originally Posted by HSLD

Yep, you've gotta turn the KVARs knob until the light stops blinking - THEN throw the bus tie.

SYNCHRONIZED WHEN LIGHTS ARE OUT

By definition, that means out of sync when the lights are on. Kindly do not close the bus tie breaker when the lights are on...

Quote:
If you couldn't get a generator on line as a new, wet behind the ears, FE and you turned to the left seat and said " Cap'n, we have a Phase Un-balance!"......... I guarantee you the response would be, "What the he11 is that?"

"Whatever is customary..."

#14

IluvRNP , 01-01-2010 11:51 AM

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Quote:

Originally Posted by SomedayRJ

SYNCHRONIZED WHEN LIGHTS ARE OUT

By definition, that means out of sync when the lights are on. Kindly do not close the bus tie breaker when the lights are on...

Or blinking.

#15

Phantom Flyer , 01-02-2010 07:02 AM

Snakes & Nape

Correctly Stated

Quote:

Originally Posted by IluvRNP

As I recall the 707 (preceded the 727) was about the same.

You're absolutely correct IluvRNP. The Seven-Oh (B-707) was the first of the long Boeing line to utilize that type of electrical system. That philosophy continued through the 777; however, a new design has been implemented with the 787.

I thought that the 777 was unique in that the APU had a 90 KVA generator that would start both engines simultaneously, run both packs and carry 110% of the rated aircraft load. I guess the new B-787 will top that as III Corps posted.

Good day mates...and "let's start 1 & 3 and delay #2". Boy, those were the days !!

#16

alarkyokie , 01-05-2010 12:08 PM

Weekends off? HA!

Glad to see someone mentioned the 400hz/60hz diff in aviation power...
Here's one to think on; a Weller soldering gun (110-60hz) will work on
400 cycle, but a 400hz device won't work on 60 cycle. Why?

#17

IluvRNP , 01-06-2010 05:04 PM

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Quote:

Originally Posted by alarkyokie

I am clueless other than the 400 cycle stuff was three-phase.

#18

SomedayRJ , 01-09-2010 06:36 PM

Gets Weekends Off

Quote:

Originally Posted by IluvRNP

Or blinking.

If one light is on while the other is off, something's rather wrong with the generator.

#19

IluvRNP , 01-11-2010 06:22 AM

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Quote:

Originally Posted by SomedayRJ

If one light is on while the other is off, something's rather wrong with the generator.

I just recall that blinking lights meant "don't close the breaker." I haven't flown a 727 since 1983.

My point was that captains at my airline did receive both initial and recurrent training F/E panel time.