102
votes
What are insulated screwdrivers for if you’re not supposed to work on a live circuit?
The idea is to not rely on any single point of failure. For you to be planted six feet under, you want at least three things to have gone badly wrong at the same time.
Your lockout padlock fell off.
...
- 24.5k
75
votes
What are insulated screwdrivers for if you’re not supposed to work on a live circuit?
A de-energized circuit is like an unloaded gun
Once I worked on a circuit. I shut off the breaker (I knew the circuit well, since it powered the lighting in the electrical parts crib) and double ...
71
votes
Does a 2100W angle grinder need an earth pin?
Your grinder is a Class-II Double Insulated appliance and therefore does not require a ground/earth connection.
But even if you did decide to fit a 3-pin plug, what would you connect the 3rd pin to?...
- 7,159
69
votes
Is it safe to remove the bottom chords of a series of garage roof trusses?
Absolutely not safe.
Those trusses were engineered with a heavy (critical) dependency on the bottom chords, which are in tension. Removal has left them extremely vulnerable to collapse due to ...
- 144k
66
votes
Accepted
What are the dangers of operating a mini excavator?
OSHA has a search engine. Many accidents are not reported to OSHA, in particular, amateur/homeowner operators like you don't have a reporting chain to OSHA. But here are those OSHA knows about.
...
64
votes
Why is my fire extinguisher emptied after one use?
Fire extinguishers (here in the US anyway) are REQUIRED to not be usable after being discharged, partial or not, because you can never know HOW MUCH extinguishing material was discharged by just ...
- 15k
63
votes
Accepted
Why don't bookshelves come with wall mounting screws included?
From the linked assembly instructions:
Screw(s) and plug(s) for the wall are not included. Assess the
suitability of the wall to ensure that it will withstand the forces
generated. Use screw(s) and ...
- 739
61
votes
Accepted
Is there a way to safely have exposed electrical wires?
Yes. This is not only safe but best practice. Tuck the capped wires completely into the junction boxes to avoid accidentally snagging on passing ladders, wallboard, etc.
If the room continues in ...
- 14.8k
57
votes
Why has my 10 year old ceiling fan suddenly started shocking me through the fan pull chain?
DANGER!!!
This sounds like a ground fault. They are particularly dangerous if you get wet, which is why Ground Fault Circuit Interrupters have been required for many years in kitchens and bathrooms, ...
53
votes
Accepted
Is this 230V steampunk metal robot lamp safe?
It's dangerous. You've spotted one important flaw but it can combine with others to make a really dangerous product.
I originally suspected it was made in Europe by someone with more interest/...
- 7,276
51
votes
Accepted
Should I tilt my DIY self-standing bookshelf backwards to prevent it falling down?
Use Screws Anyway
If it was me, I would quietly ignore "I am not allowed to secure it using screws in the wall." We are talking about a couple of screws here, which would leave ~ 1/4" ...
45
votes
Is my repair to this plug safe?
That plug needs redoing. Urgently. It is unsafe.
Make sure the clamp is on the covering for the cable not the
individual wires
This is a correctly wired UK plug... different live & neutral ...
- 520
44
votes
Is there a way to safely have exposed electrical wires?
With the breaker off, put a wire nut on each wire separately (don't nut them all together!) and you're good to go. That is the proper way to terminate unused wires, whether the breaker is to be turned ...
- 8,891
44
votes
Is this two-110-to-one-220 adaptor as fire-hazard as it looks?
There is one more hazard to this kludge that hasn’t been mentioned yet. That is the risk of electrocution! If you plug in one of the 120 volt plugs and have a 240 volt load connected to the other end, ...
- 13.2k
42
votes
Is it safe to install 3-prong GFCI with only a hot and neutral?
Absolutely!
There are a number of different functions that an ordinary ground wire performs. A GFCI, despite the "G", does not actually need a ground wire to function. In fact, a properly ...
42
votes
How can I know if one extension cable and outlet can handle so much electricity use?
The four pumps will require 9.2 amps. Your outdoor outlet has a breaker that's either 15 or a 20 amps so if nothing else is on the circuit, you'll be OK. If you have other stuff plugged into that ...
- 83.9k
41
votes
Should I be worried about this giant crack?
Yes, you should be concerned, IMO.
Some movement in a house of that age is normal, but a crack of that size (especially considering that it's been repaired once already!) suggests that you have some ...
- 3,458
38
votes
What kind of gloves should I wear during electrical work?
Depends on the voltage you're working with.
If you're working in a residential setting, simply turn off the power and wear any type of glove you find comfortable (including none).
If working in an ...
- 132k
35
votes
is it possible to turn this dumb-waiter into an elevator?
No, it can't. The design presupposes that it is only going to be used for food. It will not be robust enough or safe enough for people. Unsafe meaning, collapsing and falling down or just people ...
- 7,052
34
votes
Accepted
Why is my fire extinguisher emptied after one use?
If it's a dry chemical extinguisher (seems likely, most common, particularly with a pressure gauge) the simple answer is that the valve has got dry chemical dust in it and no longer seals properly as ...
- 223k
33
votes
Accepted
Can I safely plug a 15A 100V appliance into a 20A 250V wall outlet?
No. That is a NEMA 6-20 receptacle. Your NEMA 5-15 appliance is specifically designed to not plug into it.
Because it would destroy the appliance if you did.
That is why the system of plugs works ...
32
votes
Is it safe to remove the bottom chords of a series of garage roof trusses?
With no bracing above, you might want to check the out side walls - they are probably already spreading. Once they start moving the stabilization and repair can cost many thousands if the roof stays ...
- 103k
31
votes
Accepted
Is it safe to use a drill bit with a half broken tip?
The fact that part of the bit has broken off does lead one to believe the rest of it may be in danger of disintegrating during use with the potential for bits of metal to go flying in unexpected ...
- 47.9k
29
votes
Is this cord bend ok on electric range?
I'm not certain what guage that wire is but many manufacturers will cite a minimum bend radius.
It may or may not be code compliance wherever you are in the world.
I suspect that wire has a minimum ...
- 9,927
29
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
Unless you shattered the insides of a normal outlet, you wouldn't be able to short out the outlet using a multi-meter.
Looking at the picture below,
each female part of the socket is in its own ...
- 83.9k
28
votes
Does it cause problems to overtighten connections on receptacles/switches?
Recent (last 10 or 20 years, maybe a bit more) code says to use torque wrenches/screwdrivers for all connections now.
You found some problems with going too tight. In addition, you also squeeze the ...
- 28.3k
27
votes
Is this 230V steampunk metal robot lamp safe?
The safety solution is to either add a grounding using a grounded cord with the ground branching off and attaching to the metal as close to where it enters as possible.
Or you can convert the lamp to ...
- 12.8k
27
votes
Accepted
What is the reason for electric heaters saying to never use an extension cord?
Well, you really nailed it. It's the fact that normal everyday garden variety extension cords are usually 16 AWG, or maybe 14 AWG if you're lucky. The reality is, an extension cord, properly sized for ...
- 1,823
27
votes
Accepted
Paint inside refrigerator water shutoff valve—clean or replace?
At this point, I'd just replace it. You're missing the connecting nut and ice makers have different connecting methods than they did years ago.
You can get a compression valve, which is what you have ...
- 83.9k
27
votes
is it possible to turn this dumb-waiter into an elevator?
Forget it, this thing is a complete pile of junk.
But don't take my word on it. Ask your insurance company, because I guarantee this thing is news to them.
To qualify as a human-rated elevator it ...
Only top scored, non community-wiki answers of a minimum length are eligible