Background
If you want the fix, skip to the next section.
So I bought a refurbished litter robot for too much money, I know, I know – “You spent 289 dollars on a device for your cats to do their business in! Are you crazy?!” Trust me, it becomes more than annoying to have to clean up after your cats every week (sometimes 2-3 times a week when they are feeling extra generous), all of a sudden shelling out289-400 dollars on a poop collecting device becomes a very nice luxury. Saves you a lot of time and you no longer have to deal with the odor while shoveling catmanure.
I bought the thing back in March 2012 (I think) and it has a 90 day warranty as long as I don’t remove the plastic bib that is placed over the control unit (which is really just a circuit board). To mydissatisfaction, the unit begun to randomly stop during cycles after about 5 months of use. I would come home, smell stagnant cat urine, feces and litter mixture and know instantaneously there was a problem. The unit would be stuck open so that the smells trapped in the drawer would permeate the house… that’s what you want to come home to after work right?
Ire-positionedit, used the engineering pimp slap to see if that would jostle it back into submission, cleaned it, changed the litter, used less litter until I finally gave up and decided I was just going to hard wire the globe motor it uses to a Double Pole Double Throw (DPDT) switch for manual operation.
Duringdisassembly I found the kink in the design!
The Problem
Forgive me I don’t have the pictures right now, but I will be sure to add them soon.
So it turns out that this unit is made of flexible plastic, which of course would be fine if there weren’t any parts that were dependent on there being no movement. So I noticed a few problems, observe as the globe rotates, it meets resistance on the track because it is not perfectly round in some places, because of this it can trip the same sensor that is in place to prevent snags (not really clear on how it would prevent a snag, but that is how it is presented).
The “sensor” (it’s not really a sensor) is a steel cable that is suspended at either end with electrical butt connectors. One side is connected to the plastic base and the other side is connected to a make shift limit switch – which I am referring to as a sensor just to give it an easy to call by name.
When you snag this steel cable, it opens the circuit which tells the control unit to stop the motor. Now putting all of this information together, it makes sense that if the globe is rotating and its uneven edges are rubbing against the track, it will cause the flexible plastic to flex ever so slightly and snag the steel cable at unpredictable times! Thus making it seem random. I am saying random because at times the assembly would work just fine for about a week, then all of a sudden it would stop working.
The Fix
Don’t worry the fix is stupidly simple, takes 5 minutes, this just looks like a lot of steps don’t worry.
- Disconnect the power
- Remove the Globe
- Remove the Receptacle Drawer
- Disassemble the base carefully as there are wires connected to the control unit and to the pressure sensor in the foot of the base. You will need a torx bit to accomplish this.
- Separate the top and bottom halves of the base.
- In the top half of the base you locate a plastic compartment towards the back of the unit.
- Un-clip the cover of the compartment
- You will see (I will provide pictures later) two black cables connected to a switch like device where the steel cable terminates.
- Remove the smaller steel plate where one of the black cables is connected
- Disconnect the other black cable from the larger steel plate
- Connect the disconnected black cable to the smaller steel plate where it fits – or you can simple splice the cables together.
- Electrical tape the whole thing together and don’t leave any metal exposed for good measure. You don’t want interference.
- Neatly tuck everything back into the compartment as best you can, replace the cover.
- Re-assemble the top and bottom halves of the base.
- Make sure to tuck the cables back in their original places
- Reconnect the control unit
- Restore the drawer, globe and power (leave in off position)
- Make sure the globe is set to its center
- Turn on the power.
- Your unit will no longer false trip or snag itself
Please be aware, since the “safety feature” has beendisconnected, there is a possibility that your slower dumber cats might be dismembered by the unit. If they die, look on the bright side your cat might just win the kitty cat Darwin Award.
Electrical Makeup of this Unit
This unit has a fairly simple electrical system. There are two sensors, one real sensor in the foot of the unit that will indicate when to start the magic seven minutes and the aforementioned make shift limit switch. There is a DC globe motor that drives the globe (reminds me of a cement mixer). This motor is low speed and high torque. The control unit simply takes in power, has those three buttons on it for different motor positions (cycle, dump all and refill) and pays attention to the pressure sensor (and limit switch).
I am pointing all of this out so I can say: this unit is over priced to hell. At most this unit should be sold for 200 bucks.
