“Let’s go to the electronics store and we’ll use whatever memory they have on sale today” said no manufacturing engineer, ever. Can you imagine the variation in quality and reliability this would introduce into their products? But, with realizing it, many engineers do this very thing with their choice of liquid coolants.
Some try a “do it yourself” approach by buying mineral oils or a synthetic base from a lubricant distributor. Some buy “ours is the same but it’s cheaper!” oil from a tank supplier. Either way, there’s a huge difference in quality and confidence you get when using a purpose-made, manufactured and tested dielectric coolant.
When buying commodity base oils that are not designed to be used as finished dielectric coolants, customers quickly find out how little control there is in the oil’s characteristics. There can be huge swings in quality and in composition, from batch to batch and drum to drum. Critical characteristics, such as dielectric strength, moisture content, acid value, and sludge content aren’t controlled, tested or reported. Buyers don’t know what they’re getting – it worked once, maybe it will work again. Maybe.
Here’s a comparison of two Certificates of Analysis – one for mineral oil and one for ElectroCool EC-110 from Engineered Fluids.