Y_islam From India, joined May 2001, 7 posts, RR: 0 Posted (12 years 7 months 2 weeks 2 days 2 hours ago) and read 1776 times:
Here I am raising one technical point regarding indication of power in cockpit in Boeing 747-200.
The scale in combined KW & KVAR indicator in F.E. Panel shows power indication upto -20 on the negative side besides normal positive values.
My question is under what circumstances scale will show negative power?
As per my judgement when power is flowing to generator i.e. reverse flow then indicator will show negative power. In that case the generator will act as motor but rotating in same direction. Can anybody explain in more details?
Cdfmxtech From United States of America, joined Jul 2000, 1341 posts, RR: 26
Reply 2, posted (12 years 7 months 2 weeks 1 day 16 hours ago) and read 1692 times:
Indicates how hard the generator is working to produce power. I don't even remember the B747 electrical system, other than that is was split parallel.
Maybe that is a factor. Anyone remember the Classic 47 panels?
Y_islam From India, joined May 2001, 7 posts, RR: 0
Reply 3, posted (12 years 7 months 2 weeks 1 day 2 hours ago) and read 1661 times:
To Mr. lian
There are four generators running in parallel. One generator is showing negative value in a paralleled system means average demand of power from that particular generator is more than generation. So it may be concluded that if negative power indication is for real power then Gen speed is lower than other Gens and if reactive power is negative then excitation of that Gen is overexcitation .
Anybody may put more correct approach.