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

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ML 300RTW Trying to troubleshoot a system with the above xfmr. Do not have any literature or manuals. There is power to the xfmr and the timing dial has the on/off trippers installed. Turning the on/off knob or rotating the dial manually does trip the contacts but no lights come on. Ideas?? Also where can I get a Malibu manual for the above controller?

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First test your ac voltage going into the transformer. Then with the lights disconencted check the voltage at the terminals. (make sure your tester reads 12V DC) If you have voltage now, then you most likly have an open circuit or a short in your lighting wiring, or fixture socket.

Posted on Jul 19, 2010


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Where can I order some replacement ML Power Pack trippers for a ML600TW and ML 300RTW timer?

1) Copy following link for ML series trippers, troubleshoot, 5-year warranty info, and tips to keep power pack running longer.

2) Add comment if more help is needed. Jan 2013.

If you need further help, I’m available over the phone at

Jan 18, 2013 | Intermatic Inc. ML121RT Malibu Low Voltage...

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How to set up Nikon ML-L3 on D700

You don't need to do anything on the ML-L3. You need to set the release mode on the D700 to the remote mode. Press the release mode dial lock release and turn the release mode dial (pages 27, 77, and 80 in my copy of the manual). If you need a manual, you can download one at

Aug 15, 2011 | Nikon Cameras

1 Answer

Have an ml60t low voltage transformer timer purchased with house and now instruction manual. neet instructions, esp how to set it with pics

I don't know of a website that has picture-steps for setting Intermatic/Malibu power pack.
The manual has a few illustrations for the do-it-yourselfer.
You put black and red put trippers on the dial, connect wires to A and B terminals, connect lights to wire, plug power pack into outlet. To check operation, listen for power pack making humming sound, manually rotate dial two times and then line up current time with arrowhead located on inner dial, watch if dial is rotating and keeping good time, rotate manual override knob and see what happens.

ML60 power pack does not show on Intermatic sell sheet.

Manuals show on following page: click on model number for Instruction manuals in English Spanish French

Open following link for troubleshoot, warranty, parts, tips etc:

Add a comment for more help.

Upvote the help.
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

Jun 06, 2011 | Hardware & Accessories

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I installed a new Intermatic 200w powerpack with 15 malibu lights using 131 watts. The lights turn on manually, but the timer doesn't work. How is this possible.

More information is needed.

Open following link for Intermatic-Malibu resources:

You say clock doesn't work.
Add a comment with following information:
Do you have timer with analog dial?
Does dial rotate as time passes?
Does dial keep good time?
Have you put the black and red trippers in place?
Are trippers push all the way down?
Have you set current time by rotating clock dial 2 full turns before rotating dial to current time?

Intermatic/Malibu ML series timers come with 5-year warranty.
Product is covered by warranty.

Upvote the help.
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

Jun 01, 2011 | Malibu ML200RT - Low Voltage Power Pack...

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I just purchased Malibu ML 600 TW transformer, and ran wire and attached lights, but I can't get any of them to work. Perhaps I'm wiring it incorrectly? How do I test the transformer to see if it is...

Malibu website
Malibu manuals

The power pack has a humming sound >> put your ear close
Plug in a hair dryer on same plug to see if you have power
Check the GFI tripper in bathroom and kitchen
Plug power pack directly into receptacle (no extension cord)
It is hard to believe you got every light wrong >> the light connections are pretty fail-proof today

1) You can test the transformer by rotating manual override counterclockwise >> that's the on-off switch
2) You can test transformer by seeing if clock dial rotates with passing time > the clock must rotate
3) You can check if wires have power > disconnect wires > use another wire to scratch across both terminals to see if there is a spark

4) Did you put the red-and-black tripper pins on the dial? Red = ON Black = OFF

5) I think you forgot to set the time of day correctly
- put in tripper pins.
- rotate center dial clockwise to present time
- now, rotate dial two more full rotations and come back to present time

If the dial will not rotate or transformer does not have power, then the transformer is defective.

Oct 09, 2010 | Malibu ML600TW - Low Voltage Power Pack -...

1 Answer

Want to know how to set the timer intermatic

Following page has instructions and troubleshoot you might find valuable. Including photo of tripper installation.

To set ML series power pack that has analog dial, place trippers on dial at times you want timer to turn on-off. Dial has hours showing with dark background for nighttime. To set current time, rotate dial clockwise two revolutions and then line up current time with arrowhead located on inner dial. Manual override switch is round knob located upper left of dial.

Upvote the help.
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

Aug 06, 2010 | Intermatic & Malibu& 300 Watt Power/Pack...

1 Answer

I have lost the little plastic pegs that turn the time on and off can you tell me where I can buy them.. Home Depot and Osh do not have them

According to Intermatic literature, ML series Power Pack uses 107SB189 ON tripper, and 107SB192 OFF tripper. I have not ordered these trippers and no image seems available.

Red On tripper available at
Black Off tripper available at
Tripper order form

For more information on power packs:

Jul 08, 2010 | Intermatic Malibu 300W Power Pack...

1 Answer

Repair for Emerson MW8102SS microwave

What probably happened when the power went out is that you had a power surge or SPIKE as well, either before or after power was lost and then restored.

This sometimes can happen just before the power trips at your substation that feeds your house, or else it can happen when the power comes back on.

There are safeguards that are suppose to be in place to prevent this from happening, but sometimes they fail as well.

If you are in a bad area that has frequent power outages I would suggest adding an appliance surge suppressor to your microwave - similar to those like they use on refrigerators.

If your microwave is a 110VAC unit and somehow 220VAC is crossed circuit wise (as in underground, etc) then the same thing can cause your present day problem as well. Happened to my neighbor once and the same thing happened to their Litton Microwave. They gave it to me free, as they were just going to throw it out anyway.

I was able to open it up and get the part # off the L.V. XMFR and ordered a new one for like $10 direct from the XFMR mfr after getting their factory phone #. Litton wanted $36 for their same identical part. $$$

When this power outage happens like it did to you then you get a surge of current that will overload the primary side of the LOW VOLTAGE Transformer (XMFR) and causes it to go open circuit in the secondary - as in - it makes a break inside the XFMR itself causing the Control Panel to go dead as well. Because this AC XFMR is a step down type that takes 110VAC and drops it down to say maybe 18-24VAC you can see why it wouldn't like 220VAC on the primary side - as then the secondary side would rise up to say 36-48VAC which is way too high for the DC rectified voltages that run the Control Panel logic circuits, etc.

Nothing will work at this point except maybe for the cooking chamber light - maybe? If the Low Voltage XFMR has a fuse in it's circuit that fuse can be blown. If there is no fuse for that circuit then the L.V. XFMR has to be replaced. Usually the XFMR part will cost anywhere from $18 to maybe $35 if you can get one.

If you know someone that is handy with a DVM (digital volt meter) perhaps they can OHM out the primary and secondary side of that L.V. XFMR for you as I firmly believe that is your only problem.

One thing you might check first though is if there is a Circuit Breaker (CB) on the back of the MW unit. If it has one chances are it may have tripped, and by pushing the popped button back in - your problem would be solved hopefully. IF it even has a CB.

Hope the info helps out?

Best regards,


Mar 03, 2008 | Emerson MW8102SS 1100 Watts Microwave Oven

4 Answers

2003 Phone- no dial tone GE CORDLESS 900MHz

I am having the same problem with general electric model 27939ge3-a . I am very displeased with the GE website(s) as it is difficult to manuveur around to find any user manuals.

Next time I purchase a phone, I will check the manufacturer's help support first.

As to a solution. I may try purchasing a new battery. Perhaps it is a power issue

Oct 30, 2007 | Uniden Cordless Phone

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