I'm setting up a U6 and its been going pretty well. I have to complement LabJack's documentation, software and support people. I'm building what I call a RED system; that is Rare Event Dectector. I've got three K Thermocouples; they work great with a cheap laptop. Right now I'm configuring a LTC1966 to monitor AC voltages. While the experiment is running for days I want to know if the power failed or flickered at 2 am. That would explain the odd data around 2 am. My next goal is use the counter input to monitor background radiation and mechanical shocks as odometers. And of course, eventually, use the U6 outputs to control advanced experiments; so when something happens a 2 am I can turn on a video camera, etc. Hey, before I forget, this is a good introduction to LabJack hardware and how to properly install the sensors. In other words, always check for and remove electrical noise.
I think it is really NOT advisable for ANYONE to connect a non-isolated instrument to skin electrodes. I don't think your claim (that it wouldn't kill you if you are healthy) is not true. You have to bear in mind that the gel on the electrodes makes the skin contact resistance significantly lower than would usually exist with a wire brushing against your skin. Also, even properly-designed computer power supplies are allowed (by regulations) to have 1 or 2 mA of leakage current to ground. This leakage current has an open-circuit voltage typically >100V. 2mA is normally not harmful but if it is directed through your chest, it's iffy.
A lot of people agree with you. Safety culture tends to be hyper vigilant about the dangers of electrocution, and for very good and understandable reasons. Anyone who feels that this risk is too high should use the WiFi feature and totally isolate themselves. Just to explain my own point of view on this. In my view, the assessment of risk has to be calculated based on the probability of the failure happening during the critical time. The risk of a ground fault failure happening is computers these days is certainly low. I have never experienced one in the roughly 100,000 hours that I have been running computer systems over the 36+ years that I've had personal computers, and when I've asked my friends if they had ever experienced one with any of their personal computers the answer has been so far no. I'd like to see the data on the issue, I'm certainly certain that it exists. But if the device is reserved for demonstration only, "Oh look, it works! He kids get in here. You gotta see this!", then the likelihood of having a problem during that time must be extremely low. Certainly it has to be comparible to the risk I take from getting hit by a drunk driver one my way to the local market. If the risk is low compared to other risks that we all accept in our daily lives, then I personally am willing to take it. In addition to the probability of the fault itself occurring while the leads are in place, one also has to multiply in the factor associated with the likelihood that the delicate electrical pathways in the 5V circuitry that runs the DAQ won't blow out and break the electrical connection for before a healthy person would be seriously injured. I don't know how to calculate that probability, but it seems to me to be low. I'm wasn't aware that 2mA is dangerous if it's directed through the chest. I thought that it was ten times that. So I looked it up again. Wikipedia confirms that 20mA AC can cause defibrillation. I don't know how to evaluate the danger of lower currents for people with healthy hearts. 2mA may be iffy as you say, but I can't confirm it with the limited knowledge that I have about the subject. I do know that line current isn't usually considered an electrocution hazard. People come into contact with with it every day and almost never suffer injury to their hearts. The danger is from suffocation. Their muscles seize up and they are unable to separate themselves from the current. Their diaphragm stops functioning and so they suffocate. I do appreciate your concerns and I thank you for sharing them. Next time I'll simply recommend people use the WiFi feature to protect themselves and leave it at that. Thanks again!
@@citizenscientistsworkshop1948 We touch non-insolated things all the time, but indeed the standard for medical electronics is electrical isolation. Perhaps just the extra scrutiny (and extra cost) given to medical equipment, but perhaps also standards intended for long-term connections to a human. Nonetheless, as you mention WiFi is one way to get electrical isolation (essentially infinite). Ethernet also is an option with 1500 volts of electrical isolation. With both of these the limiting factor will often be the isolation of the power supply used for the T7-Pro (the one we include has 500 volt isolation). USB can also be isolated with a simple full-speed (12 Mbps) USB isolator, but make sure you get one that can transfer the almost 300 mA needed to power the T7-Pro.
I'm setting up a U6 and its been going pretty well. I have to complement LabJack's documentation, software and support people. I'm building what I call a RED system; that is Rare Event Dectector. I've got three K Thermocouples; they work great with a cheap laptop. Right now I'm configuring a LTC1966 to monitor AC voltages. While the experiment is running for days I want to know if the power failed or flickered at 2 am. That would explain the odd data around 2 am. My next goal is use the counter input to monitor background radiation and mechanical shocks as odometers. And of course, eventually, use the U6 outputs to control advanced experiments; so when something happens a 2 am I can turn on a video camera, etc. Hey, before I forget, this is a good introduction to LabJack hardware and how to properly install the sensors. In other words, always check for and remove electrical noise.
I've never used Labjack but it's absolutely hilarious that their software (at least the UI) was written in LabVIEW.
Great info on a great product. I have already ordered the T-7 Pro.
Nicely done, sir.
Thanks Shawn---Good stuff.
I am the son of this guy no seriously I love my dad
I love you too, you dapper little monster child. ❤️
@@citizenscientistsworkshop1948 I love you too DAD
This is so wholesome.
I think it is really NOT advisable for ANYONE to connect a non-isolated instrument to skin electrodes. I don't think your claim (that it wouldn't kill you if you are healthy) is not true. You have to bear in mind that the gel on the electrodes makes the skin contact resistance significantly lower than would usually exist with a wire brushing against your skin. Also, even properly-designed computer power supplies are allowed (by regulations) to have 1 or 2 mA of leakage current to ground. This leakage current has an open-circuit voltage typically >100V. 2mA is normally not harmful but if it is directed through your chest, it's iffy.
A lot of people agree with you. Safety culture tends to be hyper vigilant about the dangers of electrocution, and for very good and understandable reasons. Anyone who feels that this risk is too high should use the WiFi feature and totally isolate themselves.
Just to explain my own point of view on this. In my view, the assessment of risk has to be calculated based on the probability of the failure happening during the critical time. The risk of a ground fault failure happening is computers these days is certainly low. I have never experienced one in the roughly 100,000 hours that I have been running computer systems over the 36+ years that I've had personal computers, and when I've asked my friends if they had ever experienced one with any of their personal computers the answer has been so far no. I'd like to see the data on the issue, I'm certainly certain that it exists. But if the device is reserved for demonstration only, "Oh look, it works! He kids get in here. You gotta see this!", then the likelihood of having a problem during that time must be extremely low. Certainly it has to be comparible to the risk I take from getting hit by a drunk driver one my way to the local market. If the risk is low compared to other risks that we all accept in our daily lives, then I personally am willing to take it.
In addition to the probability of the fault itself occurring while the leads are in place, one also has to multiply in the factor associated with the likelihood that the delicate electrical pathways in the 5V circuitry that runs the DAQ won't blow out and break the electrical connection for before a healthy person would be seriously injured. I don't know how to calculate that probability, but it seems to me to be low.
I'm wasn't aware that 2mA is dangerous if it's directed through the chest. I thought that it was ten times that. So I looked it up again. Wikipedia confirms that 20mA AC can cause defibrillation. I don't know how to evaluate the danger of lower currents for people with healthy hearts. 2mA may be iffy as you say, but I can't confirm it with the limited knowledge that I have about the subject. I do know that line current isn't usually considered an electrocution hazard. People come into contact with with it every day and almost never suffer injury to their hearts. The danger is from suffocation. Their muscles seize up and they are unable to separate themselves from the current. Their diaphragm stops functioning and so they suffocate.
I do appreciate your concerns and I thank you for sharing them. Next time I'll simply recommend people use the WiFi feature to protect themselves and leave it at that. Thanks again!
@@citizenscientistsworkshop1948 We touch non-insolated things all the time, but indeed the standard for medical electronics is electrical isolation. Perhaps just the extra scrutiny (and extra cost) given to medical equipment, but perhaps also standards intended for long-term connections to a human. Nonetheless, as you mention WiFi is one way to get electrical isolation (essentially infinite). Ethernet also is an option with 1500 volts of electrical isolation. With both of these the limiting factor will often be the isolation of the power supply used for the T7-Pro (the one we include has 500 volt isolation). USB can also be isolated with a simple full-speed (12 Mbps) USB isolator, but make sure you get one that can transfer the almost 300 mA needed to power the T7-Pro.
5:01, ok that was funny