Engineering - September 2007

We have two thermocouples mounted in a tank and we need to measure both temperature of respective thermocouples in one temperature controller.

2007-09-10 19:00:13 · 3 answers · asked by Showman 1

since all the leds are connected, how are adjacent leds off/on?

2007-09-10 17:39:41 · 2 answers · asked by J R 1

We just had our Wartsila-Cummings and Leroy Somer generator being serviced – taken out to a workshop and after the repair, reinstalled back at our plant. The repair is for the engine parts only – the alternator parts were only serviced.



The alternator is Leroy Somer LSA 54M75, 2450 KVA, 415 V, 50 Hz, 4 poles. AVR is Leroy Somer R 449 and R 726 (see attached diagrams). After the installation we could not get the voltage ( we get 50 V instead of 415V). Site reps has checked the connections and even testing the AVR - OK.

At this time the contractor rep. did try to use an external battery – he did connect an external battery to the excitation unit for 2 seconds during rated speed and managed to get the 415 VAC as required. But when he put back the R 449 connection back to the excitation unit – we could not get the voltage level of 415 V but manage only get 50 V.



R 449 has connection from an auxilliary winding for power supply, we measured the voltage level of this auxilliary winding during rated speed and get about 88V.



Another guy came in yesterday and brought in external battery 12 V 200AH and connected to the excitation unit (he removed the cables from R 449 to the excitation unit and connected that to the battery). He did not disconnect other cables. After running for 2 minutes to rated speed, the cables from auxilliary winding to the R 449 got burnt and we stopped the test. However during the test we did get the voltage of about 488 V at the terminal.



The differential relay tripped at this time even though the genset was running without any connection to the bus-bar.





Hope to get your assistance.



Thank you

2007-09-10 17:34:18 · 4 answers · asked by MU fan 1

2007-09-10 17:01:13 · 4 answers · asked by JAMES 4

I need to take coal with a calorific value of 12,880 btu/lb and figure out how much it would cost to obtain 1 million BTUs.....any help or equation..ANYTHING would be great thanks

2007-09-10 16:18:34 · 3 answers · asked by Tommy f 1

They could make it out of anything and it could be at least as beautiful as the metallic shine. When cars bump and scrape each other, instead of replacing a panel, there would just be a bruise or wound that could be repaired for much less. The current design is so inefficient, and people hit by cars would have a better chance of less injury.

2007-09-10 15:42:06 · 7 answers · asked by veddy no veddy veddy yes 2

2007-09-10 15:41:17 · 4 answers · asked by Care-bear 1

Physics Question, please help if you can!! :)

2007-09-10 14:19:58 · 6 answers · asked by Anonymous

what are the principles of energy?
How do we control how we want it to transform? What steps do we need to follow? What do we need to know?
Can electromagnetic waves create propulsion? If so, how?
Can sound be used to push something forward? If so, how?

2007-09-10 14:14:57 · 5 answers · asked by Jonathan M 1

plz answer asap....

2007-09-10 14:01:55 · 11 answers · asked by Anonymous

What's the diffrence between a double or single french horn?
Which is better?

2007-09-10 13:33:35 · 1 answers · asked by Answergrl 1

2007-09-10 13:01:48 · 1 answers · asked by busils_1107 1

I have river in my farm garden.. It is sometimes fast and sometimes slow. I need electricity (for home lamps etc.) How can i find the design and project of electric generation from this river? I need explanation step by step. Bec i am doctor. I am planning to design it by myself. Thank you if you know.

2007-09-10 12:17:13 · 5 answers · asked by Dr Fatih 2

.. By attaching it to a stronger power source?

2007-09-10 10:47:33 · 4 answers · asked by anonymous 4

Ok what I need to know is if my power meter is 10' from my house will my power consumption be less than it would if it was 500' from my house. The reason I want to know is because of the cost of labor and power poles charged by the power company.

2007-09-10 10:18:22 · 4 answers · asked by danny_reason 1

2007-09-10 10:04:58 · 2 answers · asked by nee f 1

While testing the starting system on a car, Valmai discovered that the current flow to the starter is 330 Amperes, During the test, the voltage drop across a car starter is 11 Volts. What is the resistance?

2007-09-10 10:03:28 · 2 answers · asked by Ethan F 2

2007-09-10 10:01:40 · 6 answers · asked by Ethan F 2

2007-09-10 09:54:54 · 3 answers · asked by azkobushi 2

1. Just out of College
2. Passed FE but hasn't taken PE exam yet
3. Just Passed PE
4. Project Engineer
5. Owner of Engineering Firm.

2007-09-10 09:17:02 · 4 answers · asked by civil_seismic_eng 4

I've been having very strange problems with my phone where the other party would start hearing my voice in a jittery and cracked way, typically around 6-7 minutes into the call, it will then go away and come back after few more moments.
I've changes everything including my voice service provider and it still happening.
I've been working now with plan phone (non cordless) and it seems that it solve the problem, but now I need to find the source of the electro magnetic interference. How do I do it?

2007-09-10 08:07:29 · 4 answers · asked by asphodel_yoya 2

a farmer wants to irrigatre her land in 9 hrs. the area of her field is 25 acres. she grows alfalfa that requires 3 inches of water during the 9hrs. at what flow rate should she pump the water? provide answer in gal/min.

i converted acres and inches to feet to determine the volume and then converted that into gallons. the part that is confusing me is to figure out the flow rate.

2007-09-10 07:54:26 · 5 answers · asked by ♡♥EM♡♥ 4

We're presently expanding our embroidery and print business. The area we are running the business from only has 1 phase, but the machines (2 of them) we want to purchase run on 3 phase. These machines are fairly big and I was wondering if there are generators that would be powerful enough to run these machines. 3φ 200V~415V. Whats the rough cost of such generators. Thanks a million!!

2007-09-10 07:42:08 · 6 answers · asked by davideac 1

Give an example each of a semiconductor material that can produce red, green, and bkue LEDs

2007-09-10 06:41:16 · 2 answers · asked by sh 1

give an example of a situation in which you would use a Schottky diode(as a discrete device).

What are the advantages in this situation?

2007-09-10 06:38:04 · 4 answers · asked by sh 1

Vacancies for freshers in canada in mechanical engineering in jobs?