Need help identifying a metal oxide varistor

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There is a series of varistors placed across the inputs of AC power equipment that is marked with the AC voltage they are expected to be safe at. They take spikes from the power line. If this connects to the AC power input of your device and it could have been powered by 240 VAC in Asia, bingo. Everybody has got these. They are also sold by the diameter, with 7mm being the standard cheapo version that can't suppress much of a strike. You can find these blue things near the input of any dead PCAT switcher power supply. One source is Tyco Raychem, at Mouser. Componies I know that make red ones are Cantherm and Littlefuse. I don't have a datasheet on this part number.
If it is in series with an AC or DC input, it might be a resettable fuse. The datasheets for the red ones I have are resettable fuses.
 
Yeah, TE connectivity is the new name of raychem and AMP I think. They are **** bent on destroying their old brand names for some reason. They sold off the AMP logo to an energy drink, but I don't understand why no references to Raychem anymore. Tyco was the name just last year, even though the CEO was convicted of fraud. Doesn't mean the products were fraudulent, not as bad as Sunbeam anyway. I've been getting good TE products lately from both AMP and raychem.
 
Take a look at the "Metal Oxide Varistor" data sheet found at < http://www.thinking.com.tw/documents/en-TVR.pdf >. If the dimensions match their type number TVR05330, or TVR07330, I'd bet you have identified the part. In theory, you could increase your confidence by setting up a variable DC supply with a current limiting resistor and making a crude measurement of the clamping voltage - but the thing is rated for only a few milliwatts! (Probably intended to swallow spikes on a signal line, rather than protect a power supply.)

Dale
 
The ones across the AC input of PCAT power supplies are also 7 mm. Wimpy, like everything else in that $30 product. I've been salvaging 15 mm MOS supressors from dead 460 VAC motor drives marked "500". they have an S with two slashes through it to designate spike suppressor, by contrast with this product. I figure the transformers on my audio equipment will take 600V spikes, but above that I'd like to sacrifice a little junk metal oxide. We have a lot lightning here, as proved by many dead PC components. Lightning is somewhat suppressed by the blower on the furnace or Air conditioner, but sometimes the motors are off. Then I have installed MOS spike supressors on the AC input of my amp & preamp.
Interesting a lot of people with "energy efficient" furnaces come in to maintenance with a blown up electronic controller after a big storm. Not much to do with a blown microprocessor circuit but buy another one. My old obsolete Honeywell bi-metallic thermostat furnace controller is much more suited for this environment.
 
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