Skogsgurra,
If I may share a bad experience that I once had about connecting 2 DC motors (900 hp each). Since the connection box was not so big, all power cables where pushed very close to eachother inside the connection box. To prevent friction damage between two cables or bewteen cables and...
Maybe you should consider the use of a "hi-fog" sprinkler system. This is a high pressure sprinkler system that does not flood the entire room with water but it creates a tight water mist. With a few liters of water under high pressure, you can put out a fire in no time. Even electrical...
Have you tried measuring resistance between all phases? I don't mean the resistance of each phase (to check for open windings) but there might be a problem between two phases. Make sure that you remove the starpoint connections when doing so.
Kind regards
Peprl & Fusch (German) has a good solution for this problem:
http://www.pepperl-fuchs.com/global/en/13577.htm
This is a slip monitoring relay that uses normal inductive sensors to detect slip. This relay has alot of parameters that can be changed to make sure that it meets your requirements...
When a squirrel cage motor is used at locations with high humidity (outside or maritime environment), most of them have a standstill heater inside. However I've seen motors without a built-in standstill heating but they where heated by automatically applying 24V to 2 phases when the motor is...
Some Ormazabal breakers have to be charged by pulling the switching lever counter clockwise first. This action is needed to charge the springs and allow it to open in case of a trip.
Then the breaker can be closed by turning the switching lever clockwise and counter clockwise to open.
On those...
- Is there any loss of output power?
- Is the excitation current within limits?
- Is the generator still producing or is it completely out?
- What happens when you let the rotor spin without producing (without excitation for example?) at the same rpm as when the vibrations occur? Do you still...
Is the rotor balanced properly? Is the generator connected straight to the grid or is it being rectified & inverted first?
Do the vibrations occur also when you pitch in the blades without generating power?
Thank you, Petronila
So what I understand out of this document is that the out-of-roundness tolerance is depening on the peripheral speed of the commutator (wich makes sense).
What I don't understand from this document is that the commutator surface should be as smooth as possible. Because in...
- Is there a rule of thumb for the ideal roughness of a commutator surface for DC-machines? I've found an explanation that was really helpful and they indicate ideal values (Ra 0,8 - 1,2 and Rz 5-8µm)
My question: Isn't this value depending by the size of the commutator? Is the ideal roughness...
Yes, in my case the gyro found it's original heading without adjustment. I believe it was also a standard 22 type.
I've read in the manual that the time to resettle is depending on the sea state (movement of the ship).
When I was in this situation, I was asked by an Anschutz engineer to cut...
The quick settling function works faster if the ship was berthed when the power loss occurred (because it uses the last known heading).
I've had the same problem while at sea and it took about 1 hour before the heading was restored up to an accuracy of maybe +/- 5 degrees and I think after 2...
Thank you Gunnar & Waross for your reactions.
When we were adjusting the neutral point of a DC-machine we did not succeed to get the voltage to zero (think arround 100mV) but we adjusted it as close as possible to zero. Is this acceptable or do we absolutely need 0mV. This was a Indar 900hp...
