DO NOT BUY 1% Resistors from Amazon. I REGRET IT.

◤Contents◢
0:00 Introduction
0:10 Resistors I Examine Today
1:39 Lead Wire Materials
2:33 1% ERROR ??
5:05 Relationship Between Temperature and Resistance Value
6:29 What Happens if You Apply Rated Voltage?
8:00 Conclusion: Is it OK to Buy Resistors on Amazon?

■Business inquiries

[rickvia]

Growing up in the 70's most of the resistors were 10% tolerance in the projects I built. 5% were rare and 1% were unknown to me.

[gabotron]

My biggest problem with these 1% resistors, is that the blue body makes it very hard to read the color bands!

[jacquesmertens]

My wife is a huge resistor, with 0% tolerance.

[riccardoiacob]

I always consider 1% Amazon resistors as 5%, so there are no issues. If I need more precise resistors, I'll buy them from an authorized distributor.

[Sine]

I have been bitten by this more than 10 years ago.

It turns out these "not quite 1%" resistors are actually 5% carbon film instead of 1% metal film. That indeed gets really obvious when you heat them. Metal film has a PTC effect. Carbon NTC.

[smeggyhead]

3:22 That is not a Kelvin measurement setup. The contact resistance to the resistor will affect your result.
For a correct Kelvin measurement, the sense and drive wires must connect directly to the conductor to be measured.

[Tibbon]

I'm really digging your videos so far! Short, no clickbait, easy to understand. Keep it up!

[mtnwildernessfamily]

I purchased that very same Elegoo resistor set on Amazon. I gave it 5 reviews. It's been over a year now. I've been using them for quick projects, mock ups to test. Then I switch over to SMD resistors for production. HOWEVER, a new IoT circuit board I created, I decided to use these resistors and not SMD. I have so many of the Elegoo, I figure I'd use them for this simple IoT device that just measure temperature, has an RGB LED that flashes each time a MQTT packet is sent. Less than two months and the three out of the five resistors have failed for such a small IoT circuit board. I soldered up a another board, four months later, one resistor fails for the green LED. Changing my review to 1 star!

[gblargg]

7:35 He knows the trick of the skin just above the lip being very sensitive to heat. I do this all the time for detecting warm components without even having to touch it, just get it near.

[zxztv]

Thank you for the english voice dub :-D
Those blue body resistors are always a pain to read, but that's the standard for those metal film types.

[DrHarryT]

Keep in mind that the copper core of the leads not only improves electrical conductivity but also thermal conductivity to the PCB traces for thermal dissipation.

[federicoberni]

Very high quality video, you definitely deserve more subscribers and views!

[rickschlosser]

I work in the measurement industry. We bought true ‘precision’ resistors. They did not have color bars, they had the resistance printed right on them. (Number)

I believe they were 0.0% tolerance, in other words bang on.

But the resistance values available were limited as we usually only needed certain values. 250 ohm was very common.

[johnrehwinkel]

Anything from amazon is going to run the risk of poor quality. Even well reviewed items, if you pay for a genuine item, and the seller ships a genuine item, you can still get a fake, due to amazon's "equivalent merchandise" policy, where they will ship an "equivalent" item from a closer warehouse for faster/cheaper delivery. The problem is they trust the vendors as to what is "equivalent" and they do business with a lot of sketchy sellers.

[-vermin-]

Yeah I got a full refund when I sent photos to the Chinese seller showing that the resistors were mostly outside the specified 1% tolerance of the bulk pack I bought. They know. They just don't care.

[davidfalconer]

When making ANY electronic project ( with old or surplus resistors ) ALWAYS test them first ... this takes time, but MUCH less time than having to fault find the non working circuit ! .... Old carbon composition resistors ( useful in RF circuits, very low inductance ) nearly always rise in value with age, the colour bands just form a guide ! ( from someone who mends valve ( tube ) radios .... DAVE™ ) 🛑

[Milosz_Ostrow]

An important consideration is how resistance changes over time with application of rated power. If the resistance "ratchets" up or down with repeated application of high current, it can make your circuit fail in a matter of days or weeks, instead of performing reliably for 10-20 years. There may not even be visible evidence of burning or overheating. This information may be revealed in the manufacturer's specifications. Read the data sheet carefully!

[tomsherwood]

If you need high quality precision resistors, you just have to cough up the long green for something like Dale or Vishay metal films from a US supplier or seller. In solid state projects, at least, generally the power dissipated in your hobby grade resistors is not enough to threaten their existence.

[PanamaSticks]

45 years in electronics manufacturing. Blue is a very common color for a resistor body. Easy to read the value.

[hoofbags]

Agree with gabotron94: hard to see the colour code without a microscope! I initially met these resistors through a Vellerman kit, so assumed they made them as well. I feel it would be counter productive to knock resistor manufactures too hard, with surface mount SO components becoming dominant, we should show gratitude to any company still making wire ended components. Gr8 upload!