Hi all,
I was wondering what is the best way to make a piezo sounder replicate the Zulu morse code signal dah-dah-dit-dit.
I have tried using a decade counter driven by a 555 timer but found this a bit sensitive. I would even be open to the idea of something programable.
The main specs are...
Thanks niallnz, this is something I was concerned about. The guy doing the crossflow and mechanical design is installing a brake (and was going to do so regardless of generator type). The brake may be necessary as there is a pump that is also being piggy backed on this system.
To quantify the cost issue, the synchronous machine is 15% more expensive all up. This includes the auto-sync unit. That equates to about NZ$2000 more expensive. But in rural areas there is a growing need, in NZ anyway, for reactive compensation, which some lines companies are now...
Hi All,
I am designing the electrical components for a 200 kW grid connected hydro scheme. I have done a cost comparison using a synchronous (genset) generator and an induction generator (with caps) and the two prices are very comparable.
My preference is to go with synchronous as this is...
Thank you both for your info.
I can clarify that this is a grid connected station and that at this time there is no need for islanding. I am 90% confident that we will be going synchronous for this project.
jraef: FYI, you mentioned synchronous generators and wind turbines. Refer to...
Hi All,
I am designing the electrical components for a 200 kW hydro scheme. I have done a cost comparison using a synchronous (genset) generator and an induction generator (with caps) and the two prices are very comparable.
My preference is to go with synchronous as this is what I am familiar...
Once again thanks for the replies.
To those who have argued that the delayed pulse will not improve speed accuracy I have come around to your way of thinking. The way I look at it is: How can just copying one signal give you any more accuracy?
You need to have some direct sensing to get...
Thanks for the answers.
At this point I should let it be known that as a precaution I have designed the facility to install a second prox a while ago. I have 2 concerns with this though:
1) I doubt the gearbox manufacturer has been able to accurately drill the prox mounting hole to obtain the...
At this point I am trying to avoid mechanical solutions. When we make up our next range of gearboxes we will then increase the number of teeth or possible use encoders.
Hi all,
I have an application where we sense rotational speed by using an inductive proximity sensor to send pulses to a counter card on a plc every time a gear tooth passes the prox.
The problem I have is that the resolution is a too low and our speed output is not accurate enough. I have...
Once again thank you for your help.
I believe I have this sorted now.
IRstuff: just to clarify, the network I am fault finding (which I didn't design :-) ) seems to be working on the 2 wire method with no signal ground. This network has blown the com ports on 2 plcs. So now I intend to...
Thank you for your comments.
The network described in my question is not the network I am fault finding. The actual network is more complex.
There seems to be some contradiction in the 2 answers provided. The exert from IRStuff says:
"Proper operation of the interface circuits, whether...
Hi All,
I am trying to get my head around RS485, especially earthing. I have a simple question that should help me clarify some misunderstandings.
If I have one PLC powered by a battery and another powered by a seperate battery that are connected by RS485 (2 wire only) will the communications...
Hi all,
I am in the situation where we are wanting to determine the fault ride through capability of our synchronous generator. I know that these things can be modelled using the inertia of the generator, AVR charecteristics, etc. But how would you go about testing this in the field?
Do you...
