power electronicsresistors
I have been reading much about pulse power handling in THT resistors. I have concluded that for applications with pulses higher than rated power or voltage (like RC snubbers, or on AC line which may be tested to kV surges), the best to use are carbon and metal oxide.
But I could not find any comparison between them.
Does anyone have any afinity for one or the other type ?
This (https://www.digikey.com/eewiki/display/Motley/Resistors) says that metal film are better that carbon type resistors
Resistors cases are usually tan, brown, blue, or green, though other colors are occasionally found such as dark red, dark gray, pink and light green.
Is there a standard color coding for these parts to identify the component and its composition?
Not really however tan tends to be carbon film, whereas a blue/light blue resistor is likely made of metal film. Resistors with 5 or 6 color bands are almost always metal film. Take for example your second resistor, it has 5 bands while the one above it only has 4.
Your items from top to bottom, (The power ratings are just a guess, and the links show a similar item.)
*As @JYelton pointed out, measuring it with an ohmmeter would be definitive in separating resistors from inductors. Inductors wouldn't obey the resistor color code and thus measured resistance wouldn't agree with the markings.
How to Tell the Difference Between Carbon & Metal Film Resistors
Relax. First off, the link does not necessarily point to a carbon assortment - the description does not say. What it does say is that the assortment replaces an earlier kit which did use carbon comps.
Regardless, for what you're doing there is no difference. The composition of the resistors has nothing to do with your problem.
And what is your problem? At a guess, you're reading the color codes wrong. I recommend you get a cheap mulitmeter (you can get them for less than $10 on eBay), and use it to check your resistor values.
Best Answer
You mention both voltage and power surges, and refer to several different types of resistors.
Carbon film resistors are not great with handling power surges.
Carbon composition resistors, as one might imagine are much better, but they are scarce these days.
Metal oxide film resistors are often well specified for power surges and for mains use.
Metal film resistors are usually not well suited to power surges.
Voltage surges, insofar as they do not create power surges, are a separate issue, and have more to do with the physical size of the resistor and the details of the film geometry.
Wirewound resistors are probably best suited, especially the ceramic type, however they tend to be bulky, are not available in very high resistance values (the wire gets too thin to be reliable) are generally more expensive, and often have a lot of inductance.