What is it?

I am working on a power supply for an IGT gaming machine. (made during the mid 90's)On the output of the switched power supply is a square yellow, plastic envelope with two leads, .0625"x 1.5"x 1.5" device with id info as follows: x30v,and under that u600. on another unit, the id is: x30v , then u900.
It may be a mov? It reads .10 ohm in circuit. Could it be a planer inductor?(made by ferroxcube)
circuit schematics are unavailable,I am not a factory tech. Any thing?art

 

The .1 ohm reading tells me it is not connected like a load on the power supply. Or is it? If you do that, it is a short that will stop the power supply from working.

Could you describe the way it is connected more clearly?

 

It seems to be a resettable fuse, also known as a polyswitch, with a rating of 30V and probably 600mA and 900mA. But, check the Vishay and Littelfuse websites.

 

Thanks. I looked it up on digikey. Polyswitch is a brand of te technologies and the 600 and 900 seems to match 30v at 6 & 9 amps respectably,hence the larger size..thanks again,this really saved my butt...