# Tag Info

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ppm = parts per million, analogous to percent = parts per 100. So 1 ppm error is equivalent to 0.0001 % error. In the context of accuracy, it's, like percents, a dangerous unit to use, since it is not always clear whether it refers to a fraction of the maximum signal, to a fraction of the actual measured value, or to an absolute error. For example: you ...

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A "force" in a PLC is the act of forcing a memory bit on or off from the PLC programming software. It is used exclusively for testing. Forcing a bit on or off over-rides all other PLC logic. You can think of it like both setting it and making it read only. "set" a bit is also an option with most PLCs and is also useful for testing. It differs from "force" in ...

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It may be dependent on the industry, but in my experience that type of information is not included on a P&ID for instrumentation lines. Instead, there is an Instrumentation Installation Specification which defines the requirements for these lines, including material, size, routing, type and location of valves, etc.

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My experience is there is no particular standards for saving sensor data. Usually one just picks a format that is useful to the task at hand. If, for instance one wants to do post processing analysis in Excel then CSV formatted text files work pretty well. If you do use CSV, then just save numerical values. Don't add text indicating units to each number as ...

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From Tip #16 — What is the condition of your diamonds? Example d), as I’m sure you can easily figure out, is a heater. With all other things being equal, this one shows the inward arrows adding thermal energy to the hydraulic oil. I have left out the coolant flow arrows, which is common, meaning the coolant circuit isn’t specified. Symbol is clearly a ...

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I'd call the blue part the transmitter housing. This usually contains electronics for sensor signal conversion, which converts the sensor (or probe) low level signal to a standard 4-20 mA signal. The sensor (probe) is the metallic cylinder. And the sensor head (containing the sensing element, membrane/coil) is usually located at the end surface of the ...

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Why not mount the pressure gauge to the cork itself,so that the gauge remains on the ground with the cork? (i.e. gauge inserted in a hole in the cork or similar setup) If you were hoping to measure pressure over time as the rocket rises, you can get a pretty decent estimate as follows. This method does assume that nearly all of the gas is generated prior ...

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The confusion arises in terminology. What instrumentation engineers call a gyroscope is actually an integrating gyroscope or rate gyro, and what they call a gimbal in gimbal lock isn't the gimbal used to mount the gyroscope itself - the gimbals are used to keep a platform housing three gyroscopes level. A standard gyroscope will point in the same ...

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Have you tried a gauge guard? It's a simple diaphragm that allows pressure to transmit, without the liquid crossing the barrier.

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It depends on what your data looks like. I recently got some accelerometer data that looked like this after running it through Python's Scipy fft function: The results are pretty straightforward- natural frequency at about 5.5 Hz. In that particular case, the analysis was basically trivial- 20 lines of python, most of which was importing and plotting. If ...

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Fit a dummy test hose with no leaks - a solid tube for example, then pressurise the system to a known value perhaps the maximum used +10%. Then take readings every 10 seconds / 5 minutes (whatever is relevant for your real tests) for a defined amount of time ie 10* the length of a normal test. Repeat 10 times. Average the results for the "loss per unit ...

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Two of those are not standard usage symbols in that way. You may to have to use context and/or a physical inspection to determine what they are. Where is that diagram from? Various organizations define symbols for piping and/or control. The International Society of Automation uses ANSI/ISA-5.1-2009, which you can officially find on their website. The top ...

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I'm an electrical engineer so this problem looks to me like an RC (resistor-capacitor) discharge. In the case of a resistor discharging a capacitor the time constant is given by τ = RC. In your case C represents the tank capacity and R is your R1, the resistance to flow. Figure 1. The top curve shows the capacitor voltage which is analogous to liquid level ...

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I would guess it's a non-standard symbol for a check valve. @NMech is correct that it looks like a diode, but that would not appear on a P&ID. A check valve is a fluid flow equivalent of a diode though. I did find a reference that shows that symbol as a check valve here.

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Use a Manometer A manometer can be mounted to your launch platform and stick into your rocket. The manometer can be made of a simple transparent tube affixed to a vertical rod with dimension tick marks along it. Measure the density of your vinegar (you could just use water density and probably be fine to a close approximation), and then use standard ...

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For a less messy way to determine the volume of shaving cream use a three dimension scanner and software that can determine the volume of scanned items. Acquire some stainless steel, plastic or ceramic tiles. Weigh a tile. Place a dollop of cream on the tile. Weigh the tile with the cream & subtract the mass of the tile. Place the tile with cream in a ...

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I suggest that you take a closer look at typical noise. I have highlight the area of the specification for you reference. The best method is to confirm is measure the output to confirm the output.

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The load cell specification should include the frequency response. Bear in mind that the load cell itself is a dynamic system (e.g it can be modelled as a mass and spring) which may affect the dynamic response of the device under test.

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As far as I can see- I think your error in measuring $\delta L$ should be zero. I mean apart from the increased friction, that might hinder the movement a bit, I don't think that you should get any error in the measurement of length.

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Based on the technical data there should not be a 70-80V AC signal in the output terminal. Either you are measuring incorrectly, a wiring issue, grounding issue or defective device. Per the technical data there could be a 40mVpp residual ripple. If this is an issue I suggest applying a filter to pass only the DC components. Below is the high level block ...

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The part in your image is a Level Transmitter, https://www.aliexpress.com/i/32711941471.html The silver bit is the transducer, and the blue bit is the transmitter/

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Usually flow orifices are very aggresive to the pressure. Everything you add has a pressure drop and doing calculations by hand of an equipment like that can be hell. So yes you should check the specs of the meter first.

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The load cell you linked to has a line item on the specs that says "Output: 2 mV/V nominal". Let's just say that you picked the version with 100 lbf full scale output. What that means is this: if you use a 1 V excitation, you'll get a response something like this Load Output 0 lbf 0 mV 50 lbf 1 mV 100 lbf 2 mV Now if you use a 10 V excitation,...

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As long as the density of the air inside the solar balloon is less than the density of the air outside the balloon, the balloon will stay afloat. This is the principle of buoyancy. Regarding wind speed, if the balloon has been made strong enough wind will not be a issue. Likewise with atmospheric moisture. The moisture only affects the atmospheric air and ...

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The element does the measuring and the indicator shows the value. If you think of a simple thermometer, the bulb at the bottom measures the temperature and the glass tube indicates the value...

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Symbol 23 is just a plugged cavity. The two incoming hydraulic lines are both blocked. No flow is exchanged between them. The designer's intent for the cavity is future use. Various cartridge valves can be inserted into the cavity for either pressure control, flow control, directional control, or other purposes. You can search "DCP-2 cavity plug" or see this ...

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You have a few questions there: Is the maximum tensile strength a property of a material ? Yes. There is such a thing as maximum tensile strength, or ultimate tensile strength. This is a property of the material, and therefore the shape does not matter. If any section of the spring experiences a stress equal to or above the ultimate tensile strength of the ...

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This depends on the sensor. In some sensors, an offset it to be expected, and should be included in a calibration curve. In others, there is a good physics reason that the actual output should be zero when the thing being measured is zero, and you should force it through the origin. Lets look at two examples: A half-bridge strain sensor with two active ...

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I've done this before. I had to be pretty careful to generate the FRF. It helped me to know the input (force vs. time) and the output (acceleration vs. time). I have done it without knowing the input. I typically plot the FFT using a logarithmic scale. When you know the input, you divide the output by the input (in the frequency domain) and the peaks ...

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