Any device plugged into the unit will get its ground through the third prong, along the power cord to the outlet and then back to the service panel. The enclosure is plastic so it is not grounded. MOVs across hot and neutral trigger a low impedance reading during the high voltage test.
I was looking up any other products I could find from superdanny due to someone recommending the superdanny 22 outlet surge protector... but after seeing this, I can at least pass on this knowledgeably. The 22 outlet one is one of the most popular surge protectors on amazon atm... it might be worth making a video on it if you have time to do so.
Good review - good call. It makes you want to teardown every non-UL device in your home, eh! I love devices with long AC cords, but in this case its 'sleight of hand'... "look at the nice long cord ignore the hidden disaster!" - cheers
Thanks. It really shocked me that there was no protection from ground to either live or neutral. And then the ad on Amazon says complete lightning protection. The only complete lightning protection is to remove the device you are trying to protect from the circuit and the area. Lightning is hundreds of kilovolts at kiloamps. I've seen a lightning strike vaporize solder joints. Those little blue MOVs offer zero protection.
I AM MORE THAN typically EXPERIENCE. I will say look again, surge protection is only neutral and live at the minimum (normal extension lead don't have any protection). Again you don't flash test across live and neutral. So it that safely to say plug it in. I do a proper PAT testing myself. Anyway, go ahead and check the layout of that board before plug it in. USB don't need ground too. And yeah lighting protection isn't there which does need protection to ground.
The ground wire was connected to the ground strip upon entrance into the box, but nothing else on the circuit board, correct? Is it standard procedure for the AC ground to be tied to the DC circuit ground? If so, I wasn't aware of that. Audio guys do not reference to earth ground due to noise. The box is also plastic (therefore no need to tie ground to the box). I'm guessing the real danger is if there is a dead short (live to neutral) inside the circuitry, it would not throw the breaker until 15/20 Amps are pulled...at which point this thing could catch fire or likely melt.
A UL listed surge protector will have a MOV (metal oxide varistor) between each of the 3 legs of the circuit. Those are live-ground, live-neutral, and neutral-ground. The makers of this device didn't include the 2 of the 3 legs and claim lightning protection.
@@learnelectronics Ahhh, lightning protection -- got it now. I'm familiar with whole house surge protectors (MOV's in that case are different than surge protector strips/outlets...whole house MOV's are much "beefier"). That said, I agree with you - don't buy unless you want to risk loss to your electronics during power surges.
Or a fire. When I put 250V (not out of line for a surge in the US) across the live-ground mov, I got what? 100k of resistance? Depending on the current (my test was miliamps) 100k would go "poof" in a ball of blue flame.
You would expect to see a low insulation resistance between line and neutral because they are connected to the load. If you tested insulation resistance of a light bulb, there would be low insulation resistance value because current is flowing through the lamp back to the meter. low I.R = Current flow high I.R = No current flow Either one isn't necessary a bad thing depending on what you're testing :)
The low resistance made me think there was something wrong. On its own it doesn't mean that much. But it led me to look deeper. Once I tore it apart as you saw on the video there was only one mov between live and neutral. There was no protection at all between the other two legs of the circuit. In the US all three legs need to be protected. Also with the mov between live and neutral I would expect to see a drop down to a half of a Meg or so. What I saw was closer to a dead short and that ain't good. That's why my recommendation was to not buy this product. But I thank you for stopping by, watching the video, and sharing your thoughts with us.
Concerning stepper motor project: Take this with a grain of salt since I don't know anything about your code (just the negative sign you mention) - are any of the critical variables (and even functions) unsigned? And even if the motor/code/whatever can handle unsigned, you would have to make sure you're using the right byte size (short, int, long, etc.) (and remember (depending on the language), constants/literals might default to a size that is undesired). But, as for the other motors, I have no idea.
Paul you are very right strip is bad. there is no surge protection in first outlet the feed line wires go to outlet first then to board the line wires should go to board then to outlets but the usbs are protected good call paul its bad all over.
I was curious when I saw a 22 Port power strip with USB. I figured no way that could be safe its just asking for a short or fire. After seeing your video I would say yep confirmed.
At least you got a nice 9.8 inch cord for something else. Could the stepper problem be as simple as some bad motors? I seem to remember you've used at least some of them before. Thanks for the warning video!
I'm sorry but I found a bunch of stuff that I disagree with. Hopefully you can school me where I went wrong: (I was hopeful of SuperDanny because it has better looking ratings than Anker which is really disappointing in Anker's case.) You said the ground is "... jumpered over here" to the other pair of receptacles. (It can be seen they use a green w/yellow stripe wire to jumper them together. ) Then you say the "...ground goes nowhere" which is correct and as it should be, the green wire from the cord goes to the ground pins of the 4 receptacles, HOWEVER one might expect there to be varistors from ground to line and ground to neutral - (perhaps in this case they decided only protect line to neutral which would be a legitimate criticism.) This unit is a surge protector + USB charger. I don't know what kind of voltage that "megger" puts out but those varistors should act like "shorts" when you exceed their threshold voltage. And putting 250v on a 120v electronic device (USB charger) usually results in damage. On a simple outlet strip, testing insulation resistance between Line and Neutral is appropriate but not in this case.
Paul...did you try what I suggested? Do you want to to send you a k own working sample? You know those little motors are 5v...you didn't overvolt them did you? Why don't you just hook the motor to a breadboard and press the buttons and see. Maybe all your driver chips are fake.
Forget this power strip. Maybe was broken from factory. About the Stepper motor have you tried using digitalWrite only sequences? I see some examples using this instead of the library. try these to troubleshoot the motors: 42bots.com/tutorials/bipolar-stepper-motor-control-with-arduino-and-an-h-bridge/
@@learnelectronics OK, yes noticed you'd read and replied later. Gee, what a dangerous dud this device turned out to be. (looked so promising at first).
