Does anyone know of a measurement device rated for dust concentrations from 2000 mg/m^3 to 4000 mg/m^3? The dust particles are 20 um to 30 um in diameter.
The dust is being agitated one or two times an hour in an environmental test chamber.
I am looking for the least expensive (low accuracy...
This may seem like an elementary question but does anyone have a recommendation on how to store and organize accelerometer cables?
I have been winding each cable and placing it in a plastic Ziploc bag. Perhaps this simply is the best method?
I’ve tried plastic ties in the past but even with...
I've been using this 'nomograph' to estimate voltage drop in conductors: http://www.kepcopower.com/nomomax.gif
How would I calcualte voltage drops with equations? Is this something burried in Maxwell's equations?
Thanks
Is anyone familiar with the practice of mounting accelerometers on DUTs during vibration durability tests?
I've been hearing conflicting (and rather passionate) views on if this is acceptable from a few different people. I'd like to find discussion of this subject haven't found one so far...
I've seen "magnetic mounting" systems, such as those integrated by Technomagnete and I'm wondering if anyone has heard of these being used to mount fixtures on electrodynamic shakers?
The two concerns I see are the magnetic field of the mounting equipment interfering with the shaker operation...
Does anyone have experience with Omega's wireless transducers?
I'm looking at the temperature, relative humidity, and pressure transducers to possibly replace chart recorders and keep a history of laboratory test equipment environments.
I'm concerned about how well the OPC Server software...
Hi,
I am trying to measure the voltage across a shunt resistor with an oscilloscope (actually, one of Yokogawa's 'ScopeCorders'). Since a DC current flows through this resistor in two directions, neither end is at ground potential.
Can this voltage be measured with a single voltage probe...
My company's internet filter, Websense, denied access to eng-tips for a few weeks about a year ago. Now this appears to be the case again. Is this happening to everyone with Websense or is it just my company?
Hi,
I am looking for a power supply that can be modulated from 50 Hz to 20 kHz with a peak-to-peak voltage of 4 V. The supply must be capable of providing at least 1 A and have an internal resistance from 50 m? to 150 m?.
I have never worked with a power supply that could be modulated like...
Hi:
I believe the galvanic corrosion questions I have are rather fundamental.
First, I have heard that zinc and galvanic corrosion are used to prevent boat hulls from corroding. Is metal above the water line not protected from corrosion by the zinc since there is not a "complete circuit"...
I am looking for ideas on how to reduce I^2R drop between a DC power supply and a load without shortening or using larger gauge wire. The supply can be configured for remote sensing.
The supply output is switched across four different terminals. Each terminal is connected to a relay. If...
Hi:
I'd like to continuously control the pH level of a tank of salt water. I'm looking for insight into pH sensors, specifically if all require calibration before each use.
My set point will be 6-7 pH...
Hello,
When using tensile testers in the past I have seen fixtures that move to allow the point where force is applied to remain directly underneath the crosshead as the object bends. They give the object/fixture one or more degrees of freedom.
Is there a specific name for these types of...
I've been using shear-type PCB ICP accelerometers and out of curiosity, I'm wondering how the vertical component is removed? I've read that some accelerometers read 1G when positioned vertically but these always read 0...
I used AutoCAD Electrical 2006 to import JPEGs and measure radiuses of curves shown in JPEGs in the past. Is the JPEG import functionality the same with AutoCAD LT? As long as I can import the JPEG and draw on top of it I should be fine.
I am investigating what would cause the performance of PTC heaters to degrade.
The heating elements are a PTC carbon paste. After being powered at 14V for anywhere from 200 - 3000 hrs at various temperatures the current draw of the heaters drop from 2A to 1A. The resistance of the heaters...
Is it likely that surface mount resistors would burn out at 82C (180F) when they are not powered? I do not have a datasheet for these; a general idea of what temperature different resistors typically burn out at would be helpful.
Thanks,
David
I would like to begin working with machine vision and am looking for software recommendations. While working with robotics in the past I used Adept's machine vision/motion packages. Now I'm looking for a set of tools not related to robotics.
I would like to have multi-camera 3D capabilities...
I would like to track the movement of a part over a 1-2' arc as part of a durability test on components that are moved by motors. The motors turn about 90 degrees and the components travel in 1-2' arcs. The motors are actuated in extreme environments (-40C, 60C/80%RH, salt humidity, dust) for...
