Hello All,
Sorry for the cross-post thought maybe there might be more visibility here.
I'm looking for tips to improve over-molding of two very similar grades of Hytrel. I'm trying to improve the molding or other process parameters to get better bonding between extruded tubing of Hytrel 4056...
Hello All,
I'm looking for tips to improve over-molding of two very similar grades of Hytrel. I'm trying to improve the molding or other process parameters to get better bonding between extruded tubing of Hytrel 4056 and the Injection molded 3078, hopefully resulting in better component...
Hello All, It's been a long time!!
Does anyone else use this POS software? If so have you found a way to automate entries other than an Excel/VBASIC Macro. Our Document Control is exceedingly anal about the referenced documents and when creating a BOM it can literally take hours to reference...
BTW Compositepro
Thank you for the article, it is very interesting. I once worked for a company where I designed a treatment chamber to apply a "chemical secret sauce" [wink] to various substrates to increase the surface tension chemically. It worked almost or as well as flame treatment.
"The 'arc' in these instruments is a corona discharge where the air at the tip of the instrument is ionized by a very high electric field created by the sharp tip and high voltage. C
The manual that was linked to above said the instrument operated at 50 kHz. That is a long way from a MHz."
[ol...
@IRstuff
That I get. Unfortunately the metal cannula does have other uses so getting rid of it isn't really an option (on this design anyway). Plus as I have stated before, I'm not really worried about zones 2 and 3 What I have is much more interesting. So in zone 4 (the handle) we have...
Hopefully this sheds some light on how this is happening with AC voltage.
So worst case scenario High Power Generator, Coagulation Open circuit, device is known to be a inadvertent capacitor. How do I measure how much of a capacitor it really is, and determine where it is likely to discharge...
Best explanation I have seen so far
CAPACITIVELY COUPLED CURRENT
The phenomenon of capacitively coupled currents is more difficult to understand. It is the inducement of current through the intact insulation of active electrodes to surrounding cannulas or instruments.
Note: The term...
Clarification: Side walls blown out was from insulation failure not from the capacitive coupling, I reread what I wrote, and what I wrote and what I was trying to convey don't match. I have seen the sidewalls blown out, with weak or degrade insulation. I know what that looks like, and results...
As I said before all of these instruments undergo insulation testing before and after surgery
Here is an FDA event revolving the manufacturers of that double insulated AEM instrument. I'm not trying to create a new system, I'm not worried about zones 2 and 3 although it seems there is plenty...
@VE1BLL
I get what you're saying I really do, so I'm looking for explanations. All I can tell you is the data that I have gathered or has been presented to me as best I understand it. I don't understand how it could be charged enough to discharge at half a micro second. In fact, I don't...
@IRstuff
"Capacitive Coupling occurs whenever two conductors are separated by a non-conductor. An electrostatic field is created between the two conductors. As a result, a current in one conductor can, through this electrostatic field, induce a current in the second conductor. An "inadvertent...
@VE1BLL
That could be my own misunderstanding, but Capacitance is stored electrical charge. What I have to go on is the scientists and engineers who deal with this everyday have called it Capacitive coupling.
@IRstuff
The output voltage and frequency are controlled by the ESG. " the machine is changing its output voltage or frequency or both as duty cycle increases or usage duration increases" So something IS happening during duration. You're saying that it's likely voltage, frequency or both. If...
@itsmoked
What you're describing sounds a lot like bipolar electrosurgery, which seems all together safer to me!
I found this about the generators, although the source is old: "Most modern electrosurgical generators are isolated from earth ground, and have fault monitors that will disable the...
@itsmoked
Thanks! I figure I am going to have to pick up some equipment to test this! So these recommendations really help! Thank you! All I have at my disposal right now is an old hi-pot machine and a cheap harbor freight DMM. So I really appreciate the advice, knowing how to best setup...
@VE1BLL
Also, Thank you. What are the right terms for an AC system? All I can think to call them otherwise is conductors...
I mean this was my introduction to this phenomenon, I attached the picture earlier showing the arc through the halar tube.
Capacitive coupling: Capacitive coupling...
@VE1BLL
I get that, it's the first thing that popped into my mind when I was informed of this potential failure mode. Unfortunately, there is nothing I can do about it. The handle is separate and has to use a standard post electrode that works with standard cables and generator units. This...
@VE1BLL
I think so. So imagine you're on your back on a surgical table. Underneath you is a ground pad electrode. So it might be taking a shortcut back to the ground, or it could be with the charge it's built up that the difference in the potentials has narrowed to the point that it's taking...
