| Author |
Message |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 26, 2005 - 10:26 pm: | |
I have a question about 12 volt blower motors
One of the two 24 volt blower motors for the driver defroster heater is bad . So I though I have about 8 12 volt blower motors so I would just change them to 12 volt.
But here is the problem the 24v motor turns CCW and the others turn CW So I thought easy just switch the wires and thay would turn the other way NOT . It made no dif how I hooked up the wires they went the same way, Is there any easy way to change the direction ? I would just replace the one bad one but WOW thay cost $$$.
Brian 4905 Klamath Falls Oregon |
Marc Bourget
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 26, 2005 - 10:50 pm: | |
Try reversing the armature thru the case, i.e. flip it end for end, if the shafting and the ends will allow. |
gusc
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 26, 2005 - 11:39 pm: | |
Brian,
If it is possible to reverse the fan on the shaft you will get the air flow in the correct direction.
Most DC motors turn the same direction no matter what polarity you use; however, I think the direction can be changed by moving the brushes but not sure of that .
I don't understand how you can replace a 24v motor with a 12v one? It is possible to hook two 12v anything in series in a 24v system. I've seen this done with lights but of course when one goes out so does the other!
Most military vehicles use 24v systems and have all kinds of heater motors. The M35 6x6, the M37 Dodge and M38A1 Jeeps are probably the most common ones around. You can see the remains of them about anywhere, especially the Dodges because a lot of VFDs used them and abandoned them when they broke down. |
Tony & Kim Rian (Rianrts)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 26, 2005 - 11:42 pm: | |
Brian i wish you would have askied last month last month my wife influnced me to do a dump run and i threw out a total fan set from my amg sorry and to top it off we live in grants pass |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 27, 2005 - 2:33 am: | |
My bigest problem is it a squral cage so it has to run CCW and most motors I looked at run CW but Im still looking for something the chevys almost bolt up but the squral cage is to big and if I use mine its the wrong way.
I may have to just spend the big $$ and order a used one.
And how I can use 12 Volts I have 12 volts for all my lights and any thing that was 24 volt but charging and starting. So I well just change some wires and use 12 volt motors.
I dont see any way to flip the armature.
Found some close looking 24v on ebay waiting on e mail on rotation.
I may have better luck looking for a squral cage to rotate the other way but I dont know if the air flow will work in the blower case that way.
Brian 4905 klamath Falls Oregon |
BrianMCI
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 27, 2005 - 8:40 am: | |
It is my understanding of DC motors that any motor that uses permanent magnets will reverse direction...
Otherwise actuators would be a lot more complicated.
DC motors using electromagnets will spin in the same direction regardless of polarity.
The design of the squirrel cage housing is dependent on the direction of air flow, and while it might blow some air, I don't believe it will work well enough.
The size of the squirrel cage is also pretty critical, it has to be at least close to the dimensions of the original...though no bigger...
Brian |
Charlene
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 27, 2005 - 10:15 am: | |
Just turn the fan over if squirrel cage, turn housing over also, maybe a little work to refit? |
Gary Stadler (Boogiethecat)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 27, 2005 - 11:56 am: | |
If you have a DC motor that won't reverse direction, it is not a permanent magnet motor, instead it has windings both on the rotating armature and the fixed field. The armature and field windings will either be hooked in series (called a series motor) or in parallel (called a shunt motor) or some of the larger motors may actually have a combination of both.
In any case, if you reverse either the wires to the brushes or the wires to the fields, the motor will go the other way. The only problem that may occur is that many motors are "timed" for one rotation and will not be as fast or efficient in the other direction. They do this by rotating the brushes to a preferred position, just like the points in a car distributor, optimized for one rotation. Most of the time this is manufactured in and can't be changed.
Bottom line, try it and if it works well enough for you, there you are! Nothing lost, lots gained... |
Ken Kushner (Kudu)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 27, 2005 - 11:27 pm: | |
Hi Brian...Try www.surpluscenter.com. They carry a selection of DC motors, new and slightly used. They offer a 24 volt dual centrifugal blower. Item # 16-1056 states it makes an excellent defroster blower. Hope the info helps... |
Henry R. Bergman, Jr. (Henryofcj)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 29, 2005 - 1:32 pm: | |
Brian, e-mail me if you want. We have a local guy who can probably help you out. Motor-alternator-starter guy. All he does. Very knowledgable. No connection. Henry of Cave Junction. |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 29, 2005 - 2:37 pm: | |
Thanks guys I will look in to all of that.
Brian 4905 Klamath Falls Oregon |