How Long Should This Motor Last?

Hello,

I bought two of these motors and I'm wondering how long they will last. I would look on Google and do some research about it but I've found this problem is very motor and application specific and I feel like the best way to find the answer is to ask people that are experienced and have a good feel for this type of stuff.

So these motors will run about 5 months a year and throughout these 5 months they will run:

  • 7 days a week
  • about 30 mins continuously at a time at most
  • ~6 times a day at most

They will not be used at nights (~12 hours a day).

Furthermore, they will be used in cold temperatures of about 5 degrees Celsius.

I'm wondering, if they are used at 12v or less at all times, how long should they last. (I don't even have a good ballpark of this yet. From what I've seen on other forums, I don't know if it's weeks, months, years, decades, etc.)

If they are used at less than 12v, say only up to 11v, will this help the lifespan. Also, would taking them apart and cleaning them up each year before their 5 month season help out? If so, approximately how much of an increase in lifespan would each of these two things give the motors? In addition, I read that running them for 15 minutes at half speed to break them in can increase their life drastically.

Thanks

Expensive motor. Ask Robotshop for the MTBF (mean time between failure) specification.

Compute the total hours you motor will run in a year. Motors are rated, but not usually in the documentation, to run x number of hours before failing. You need to find that number from the mfg.

Paul

Also, the load you put on this motor will effect how long it will last.

BTW, looks like motor is 7500 RPM.

You can see the gearbox output shaft has a proper ball bearing from the picture, but no idea if the
motor itself does.

The two things that wear out in a cheap motor are brushes and bearings, and typically proper
ball bearings with seals will last fine, phosphor bronze bushings may not. Brush life depends a
lot on their quality.

Can you see if the motor itself has ball bearing races?

Stripping the motor should ensure it's life will be short !

Could you reference the document that states they need 'running in'. If the motors are designed for an industrial environment then they must be capable of meeting their design load from day one.

As others have said, ask the manufacturer. Then divide their given MTBF hours by your annual use of 455 hours for an indication of how long they may last

Alright. Some of you have suggested I contact the manufacturer.

First, I contacted the RobotShop. They said something like, "These are hobby motors, our manufacturers don't test for these specs."

Of course, RobotShop is not the manufacturer, so I l found the code for the motor and gearbox combo: FIT0277.
I looked around using this. The two websites I feel are most likely to have the MTBF info are:
FIT0277 DFROBOT - Motor: DC | with encoder,with gearbox; 12VDC; 230mA; 146rpm; 51: 1; DF-FIT0277 | TME - Electronic components (Multiple websites link to this one as the manufacturer)

and

12V Low noise DC Motor 146RPM w/Encoder wiki-DFRobot (The previous site links to this one as the manufacturer)

Do either of these seem correct? I will contact these people when I get a chance.


Finally, MarkT said:

MarkT:
The two things that wear out in a cheap motor are brushes and bearings, and typically proper
ball bearings with seals will last fine, phosphor bronze bushings may not. Brush life depends a
lot on their quality.

Does this mean that assuming all of the bearings are good, I can make this motor last as long as a brushless one, provided that I change out the brushes whenever necessary?

Thanks

Well, these places just aren't giving me an MTBF. What a shame. Anyone have any rough estimates, please? Also, I took off the gearbox and looked inside. The motor looks like it has a bushing and by the way DFRobot responded:

"Besides, could you inform why do you want to know the bearing of the output shaft of the motor, since the shaft of the gearbox is the one connected to the wheel."

It's probably a bushing. It has a silver colour the same as the motor casing. How long do those sorts of bushings usually last before wearing out?

I really need a rough estimate of time, so I'll try to kick off a discussion:
Is it possible, with the above usage, for this thing to last 80 years?

Is it possible, with the above usage, for this thing to last 80 years?

No.

BTW, you will be dead in 80 years.

Buy a few motors, run them 24/7 under load 1 week @30°C and 1 week @0°C.
Do this for 6 months then take them apart and check bearing, brushes, compare to a new motor.

PureStress:
Well, these places just aren't giving me an MTBF. What a shame. Anyone have any rough estimates, please? Also, I took off the gearbox and looked inside. The motor looks like it has a bushing and by the way DFRobot responded:

"Besides, could you inform why do you want to know the bearing of the output shaft of the motor, since the shaft of the gearbox is the one connected to the wheel."

It's probably a bushing. It has a silver colour the same as the motor casing. How long do those sorts of bushings usually last before wearing out?

I really need a rough estimate of time, so I'll try to kick off a discussion:
Is it possible, with the above usage, for this thing to last 80 years?

You have posted 38 times. So, lets use the number 38. You pick the units.

Paul

PureStress:
Well, these places just aren't giving me an MTBF. What a shame. Anyone have any rough estimates, please?

If there's no information to be found, then it'll just be necessary to start testing a few of them (or more). This just means continual running of as many of these devices as you can for 1 year, based on those conditions you wanted. If they all last for 1 year, then that will be a good sign, and there will then be at least some stats on their life.

What's the fixation with respect to how long they will last.
They are relatively cheap motors (when compared to industrial supplies) so if you want something to last "for ever" then spend say 100 times what you have already spent and buy motors that come with MTBF figures. Otherwise, do what the rest of us hobbyists do, buy cheap and replace when broken.

PureStress:
Is it possible, with the above usage, for this thing to last 80 years?

What about 80 hours?

Come at this question from the other end - choose data that you can put a number on - what is the minimum number of operating hours that would be acceptable for YOU.

...R