Running a motor at lower voltage - what will happen?

[Wendi Corbin]

I have this single speed motor: M-9000-PK that runs on 12v DC. I want to run it at 6v to slow it down, and I want to run it for long periods each time I use it. What is the actual danger? Will it explode? Burn up? Just stop working?
Is there anything I can do to mitigate the issues? From my web searches I'm thinking the danger is overheating. If I have a fan on it while it's running, would that reduce that risk? Or am I even off base with that thought?
This is going to be connected to an interactive art project, so while I don't care if it just dies, I want to make sure it's going to be safe and not harm anyone. The motor itself won't be in direct contact with people, but what it's turning will be touched, and what it's bolted to is plastic.

It doesn't struggle at lower voltage, torque is strong and it starts moving without sluggishness.

 

[Colin Mitchell]

The motor will take less current and the torque will be reduced.
If you are driving a load, the RPM will be reduced.

 

[Wendi Corbin]

Thanks so much for your reply, but that part I know already. I'm asking specifically if anything bad and especially dangerous will happen... Do you know definitively if this is a dangerous thing to do or not?

 

[Colin Mitchell]

My answer is axiomatic.

 

[Wendi Corbin]

So in that case, you are saying that it should be obvious to me that you intended to say that it is not dangerous, and that all that will happen is what I've already observed? Or are you inferring something else with your "axiomoatic" answer? Thank you for your answer, but honestly, I'm looking for answers that are are intended to assist someone fairly unfamiliar with electronics in not harming themselves or others, not condescending answers. If you have one of the former, I'd love to hear it.

 

[duke37]

I do not see any danger. It will not explode but if it is stalled the commutator may be damaged by uneven heating. The current taken by the motor will be dependant on the torque and the heat dissipated will be dependant on the current. Use the finger test !

Ensure that the power supply is isolated from the mains.

 

[Wendi Corbin]

Excellent, thank you! I'll still proceed with caution, but with a little more confidence now.

 

[Tha fios agaibh]

I agree, it really depends on the load your putting on the motor. If you reduce the voltage the current is going to go up to do the same work and will produce more heat. Another consideration is the cooling ability of the motor will be less by running at a lower voltage.

 

[Wendi Corbin]

Thanks!
The motor is rated for something like 4000+ lbs and I'm going to be putting only about 10lbs max on it, but it will be running for a lot longer than it would in it's intended function.
Do you think that running a fan on the motor while it's operating would help with the heat or is the casing maybe too thick for that to make a notable difference?

This is the motor: http://www.venturemfgco.com/m-9000-motor-gearbox.html

 

[Tha fios agaibh]

You should be fine as long as you don't exceed about1/2 of its rating.
The internal cooling will not be optimal but should still be ok the way it is.
If you can run larger wire to minimize voltage drop, I would do so.

 

[Kiwi]

My suggestion would be to contact Venture MFG with details of your application.