Transformer comes with broken fuses?

Discussion in 'General Electronics Chat' started by cheddy, Oct 31, 2007.

  1. cheddy

    Thread Starter Active Member

    Oct 19, 2007
    So I went to Fry's (It's like a 40 minute drive) and bought a 100Watt transformer to use some 220V appliances from Europe that my girlfriend owns. Well before I even plugged it in I checked the fuse and it was already blown. there was a backup fuse in the box that was also blown.

    This thing was made in china and it looks brand new, I just don't understand how the fuses are blown? Is is possible the fuses broke in shipping from china? I want to give it to my girlfriend as a gift but I don't have any 220V appliances to test it on before I give it to her to see if it will even work.
  2. mozikluv

    AAC Fanatic!

    Jan 22, 2004
    i presume you don't have a multi tester, also have replaced the broken fuse, it's a step up transformer (120v to 220v)

    1. if you have a step down transformer (220v to 120v), connect it to the output of the step up tranny. then connect any 120v appliance. if it works your tranny is okay.
    2. connect a 220v light bulb

  3. GS3

    Senior Member

    Sep 21, 2007
    I am assuming the mains in your area is 110 V and you want to use an appliance designed for 220 V so you need to step up the voltage from 110 to 220. If the transformer is good for 100 W then I assume the appliance uses less than 100 W. Right? I am assuming you are correctly connecting the 110 V side to the mains and the 220 side to the appliance. Right?

    On what side is the fuse?
    Is it an isolation transformer or an autotransformer?

    Why don't you try asking at the store where you bought it (other than the long drive)? If it is defective they should replace it.
  4. JohnBoy

    New Member

    Oct 30, 2007
    I assume that you purchased a stepup transformer (110 VAC to 220VAC). To verify the transformer, replace the fuse(s) and plug it in. You can measure the voltage at the output. If it blows the fuse(s), it's defective. To load test the transformer's output, connect two 100VAC 50W lamps in series for a load. If your transformer is capable of 100W then it should have no trouble with this load.