Question about Malibu Intermatic Inc. ML300RTW 300-Watt Power Pack with Timer and Ground S

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Malibu 300-Watt Low Voltage Transformer ML300RTW Not Functioning

I have a malibu 300 and 600 watt transformers. They are both plugged into the same outlet. The 600 services the backyard, and the 300 the frontyard. Recently, the 300 quit working. Is there a chance that an internal part needs replacing, rather than purchasing a whole new unit? I've checked the circuit breakers, which are all okay, so I'm sure it's a problem with the clock itself.

Any help you can provide, will certainly be most appreciated!

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  • jmtarutani Feb 04, 2009

    My transformer became very loud with what seemed like some sort of internal vibration. This lasted a couple of weeks before it became intermittent. This is a relatively new unit which I installed in October.

  • Anonymous May 04, 2009

    my timer stops when the trips hit the switch

  • Bob
    Bob May 11, 2010

    There are no user servicable parts for those transformers. They do have a 5 year warranty, though. Are you able to turn it on manually? You may want to check the outlet with a volt tester to make sure you are getting 120 volts, or plug it into the outlet that the working 600 watt transformer is currently using.



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My power went off at my house. After it came by on how do I reset the transformer to come on automatically?

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Try to find the receipt and take it back to the store while you still can, otherwise you'll have to deal with shipping it back to the manufacturer under the 5 year warranty. Sometimes, if you call them first, a manufacturer will go ahead and ship the product out the day or two after your call, then trust you to send it in. I did that with a Supreme water pond pump. Some companies want satisfied customers,

Posted on Feb 05, 2009


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Can you hook up two 12 gauge cables to the power pack of the ML 300 RTW transformer. Power cable would run in different directions. Thank you Joe

Hello yes you can the Important thing to remember here is not to exceed the wattage that the transformer puts out.

Add up the wattage of each bulb that you are running and ensure that you do not exceed 300 watts.

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