I'm looking for the source behind Notes 2 and 4 of Table 11(B) in Chapter 9. How did they arrive at these values?
In my mind (btw), Sola is the only choice.
Thank you for the nugget. I've downloaded it and will read it over slowly when I have time. To be more specific with my question -
Notes 2 and 4 of Table 11(B) in Chapter 9 specifically state,
"Where wet contact (immersion not included) is likely to occur...."
I have a group of powerful people thinking that these voltage limits are safe touch voltages for people in bathtubs, pools, spas, etc., and I need to prove them wrong - that these touch voltages are not safe for people that are immersed. That was where I was going with this.
HA-HA, like you say, there's always more to the question. I don't remember where I came across the description of "immersion" as being underground. Shooting from the hip, pooled condensation.
I like the topic. I was running numbers for explanation and it became quite twisted. Note 4 mentions <30V (why or where 30V - I don't know). Note 2 mentions <42.4 Peak. The relationship between these two numbers is the Square Root of 2.
Multimeters read a value of 120V AC r.m.s (or root mean square), so the meter is sampling at some rate capturing a value, squaring it, adding it to the next sample squared and so on, and dividing by that sample number and taking the square root of the total. [wow, what a bad written description - nonetheless, it's not plagiarized].
So if I took 3 samples ...
120 * (Sq. Rt. 2) = 170 peak
While we all know what r.m.s. is in general, we don't necessarily realize that it's not the peak value of the sine wave.
Truth be known, the Square Root of 2 is an approximation. -WHAT? Yes, the Sq. Rt of 2 is sooooo close to the calculated sample values of r.m.s. that everybody and their brother accepts it as such. No big deal tho, it works!
Unfortunately for your argument, I don't think that <50V is lethal. It takes more than 50V to 'push' the current thru a person. In this case, especially if the Power Supply is inherently limited (or, internally protected) - it's all good.
Down the rabbit hole:
But I didn't say lethal. I'm primarily concerned that these contact limits can be dangerous for people who have implanted cardioverter defibrillators (heart devices), if they are swimming in a pool. Any external interference with an implanted heart device can be serious. If this happens to a pacemaker, it usually reverts to constant pacing mode. A defibrillator could (in theory) send a shock when one was not needed or possibly be inhibited from providing a shock when one is needed. That is why I'm trying to find out more on "Where wet contact (immersion not included) is likely to occur...."
It's a long, deep hole.
If I can find the source behind Notes 2 and 4 of Table 11(B) in Chapter 9, and why "immersion not included" was put in there, then I can bring down the house of cards, it starts tumbling down...
Right, that category is yet another dimension. I was recently asked about Radiated Electro-Magnetic Interference for Associates who have a pacemaker working on the production floor. There are handheld measuring devices for audits AND Sensors to hang around your neck (like a Radiation Badge). I try to make it clear to everybody that all the audits and all the Designed-Out methods & procedures crash and burn the moment someone opens the Door of an Enclosure. The Electrical Box is a Faraday Cage and dampens the Field strength. The Sola SDP4-24-100LT advertises Radiated EMI values below EN61000-6-2. The reason this is important is that Switch-Mode Power Supplies multiply 60Hz to some multiple (say around 25kHz) and regulate it back down. If this is a recognized issue, perhaps an old fashion Linear Power Supply would be practical.
So what if someone with a Pacemaker accidently drops a Transistor Radio (with a 9V Battery supply) while sitting in a tub of water? I'm sure this much has been tested.
btw, Note 2 is for Table 11(A).
Yes, Note 2 is for Table 11(A) but inconveniently listed under Table(B). I agree with you - Table 11(A) and (B) values have probably been tested. Table 11(A) and (B) is not the house of cards that needs to fall, though. I still need to find the source behind Notes 2 and 4, and and why "immersion not included" was put in there. Please contact me through any of my websites and I will be happy to share further.
Retrieving data ...