Fix a LitterMaid Mega (The Under $15 Better Version)

by Rob K in Living > Pets

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Fix a LitterMaid Mega (The Under $15 Better Version)

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This goes with my other instructable. Fix a LitterMaid Mega for under $5

I was not satisfied with how the motor was running. Sometimes stopping whenever it hit a big "cake".

This one cost more then the other one, but it now has more power when it hits a "cake".

Safety Safety Safety (Don't Do What I Did.)

'This involves electricity(low voltage)and a hot soldering iron.'

I burned my thumb and index finger on my left hand trying to switch hands with the soldering iron(35W). grabbed the metal end and started to solder with out knowing I grabbed it.

I know I burned my hand, but I don't feel anything. I will throw a picture up later if it starts to blister.

No blister. The part of the soldering iron that I did grab was the area that is black from the heat.

The Parts

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There are a lot of wires in a LitterMaid litter box, so wire does not need to be bought.

What is needed (I went to local Radio Shack). $ 11.56 + tax for parts

  • Size M female power jack #274-1563
  • Full-Wave Bridge Rectifier #276-1152 (or a 6v 1A DC power supply)
  • 2 Push button switches #275-1556(not pictured but comes in a 2 pack)
  • DPDT Switch #275-664 (not pictured)
  • 25v 2200uF Capacitor (it is the purple one that can be found on the main board)It helps get the motor going and smooths out the rectifier
  • Standard Soldering Equipment(iron, solder, bandages, burn cream, etc)

Push button switches are not need if you use a DPDT that has a center off. I used one that had a center off just for preventing it from moving.

The Schematic

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This is the circuit schematic.


The Power Plug

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There is a lot of room inside the main board area, but I went with the battery compartment so that nothing would snag the cable retractor.

The screen moves on a track. It comes off the the box by two latches. Easier then working on the whole box.

AC to the DC

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This is not needed if you have a 6v 1A DC power supply.

A full-wave bridge rectifier coverts AC to DC.
Look at your box or manual to see how it wires up.

Apply power and check with a multi meter that you are getting DC.

Cap It.

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The capacitor is fairly strong it can still move the screen unplugged for a little.

Attach the capacitor positive to the positive and negative to the negative.

Push Button Switches

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The switches are from before.

Place them where you want. I placed them on the front cover.

Add wires to the switches. one wire from each switch goes to the positive wire.

Motor

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The wire for the screen motor is on a cable retractor. I added wire to the ends and ran them to the battery compartment. I also added a wire from the ground. Hot glue was used to hold everything.

DPDT Switch

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The DPDT switch is wired like the schematic. Pace the switch where you want I put mine in the middle above the two push buttons.

Wiring

||123||
||456||


1) wire from push button switch
2) motor wire
3) Ground connected to 4 and connected to ground on power
4) Ground connected to 3
5) motor wire
6) wire from push button switch


Testing

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If everything is hooked up apply power and see if it works.

Move the switch to the color and push the button.

Move switch to RED then push RED button - forward
Move switch to BLACK then push BLACK button - backward

Switches don't move how you want. It is most likely that the push button wires are switched

Short 16 second video of it working.

Dam You IE for forcing me to use Firefox to get the video to work.

If everything works put it back together and try it with litter.