Motor Type

Status
Not open for further replies.

gdeboisblanc

New member
Messages
2
Reaction score
0
Location
texas
I am really enjoying this forum as there are a lot of pretty great ideas and information here. I am building my son and electric gocart. I made the mistake of purchasing a motor before buying the controller. The motor I purchased has little information on line to let me know what type of motor it is, so that I might purchase the right controller for it.

I have been told that there are PM (permanent magnet), Series wound and Sep/Ex motors.

I purchased this motor (not at this price!)
http://www.hydrogenappliances.com/3hpmotor.html

Can anyone give me some advice on how to safely navigate this problem. I don't know which of these categories this motor falls into, or what to do to find out. I have searched the internet and there is no really go specifications document that I can find that answers the question of what type of motor this is.
I may have to take it apart and take pictures of the inside, but I really don't want to do that.
Any advise please?
:cheers2:

--taken from unit

BW16L1 (SERIAL #?)

Model # 10792N

PO 01769370000100049

Gregg deBoisblanc
Houston
 

anickode

Active member
Messages
2,297
Reaction score
6
Location
S.E. Michigan
I'm guessing it's a sepex motor based on the third lug, though I could be wrong. These motors use a seperate contact for the field winding (separate exciter, hence the name), which is typically a lower voltage than the primary motor winding on higher voltage motors. On a 12v motor, it may be the same. If it is a sepex motor, you will need a sepex specific controller.

The link you posted has a link at the bottom of the page that says "need a low cost controller? Click here". Might start there.

At 12v operating and 190 amp Max draw, you are going to need some REALLY beefy batteries that can take some serious load without sustaining damage. Normal small deep cycles and sealed/AGM batteries (like the 35ah SLA that seems to be popular here) will be out of the question. You need to look at something along the lines of a marine dual purpose starting/deep cycle, or Optima Yellow tops. Plan on at least 2 to get any decent ride time out of it.
 

alim

New member
Messages
61
Reaction score
0
Interesting find! A high wattage 12v motor would eliminate the need for multiple 12v SLA batteries in series to achieve 24v/36v/48v etc.

190A is a LOT, maybe a programmable controller could be used to limit that to something a typical 35ah SLA could handle?
 

itsid

Moderator
Staff member
Messages
11,521
Reaction score
67
Location
Ruhrpott [Germany]
12V 190Amps
this is weird...

Odd terminals too, three lug while being FULLY reversible?
sep ex, I agree, but I know no controller that's actually doing this kind of weirdness really.

looks like it's a starter motor with a new frontplate to me (repainted and solenoid removed)
IDK.. maybe some industrial heavy equipment that I'm unfamiliar with *shrugs*

their "speed controller" looks awefully like a high power dimmable LED PSU...

And as I'm seeing this motor on ebay right now...
I'm again stunned by sheer terror..

I quote:
ebay auction said:
2500 RPM at Full Load 150 amps / 8000 Free Spinning 70 Amp - High Torque!
3 hp on a fully charged 12 volt lead acid battery (13.6 Volts actual)
Fully Reversible. Rotor efficiency = 89%
2400 Peak Watts - 190 Amps Peak Load - Must use a 125 amp fuse for best safety.

150 A under "full" load...
190 A peak 'load'
all backed by a 125A fuse...
RIGHT! (NOO, no.... just furiously no!)

I smell Mantas again...
I'm sorry, deeply sorry, but I'm out, I don't even bother doing the research!

unfortunately it's an oddball three lug motor, otherwise it'd be easy,
I'd ask you to just find ANY PM brushed DC controller for this sepex motor
for a three lug you cannot just ... (not without loosing the reeverse functionality that is)

So a special controller would be needed, one that'd be extremely expensive
(I think upwards of 600 bucks is not too unreasonable.. think Curtis Controllers or so)

frankly, drop it.. sell it on ebay, use it as a doorstop on your shed ..
but other than slapping it on a battery with just a beefy contactor (200A solenoid)
and with the torque and speed that's able to deliver
- whack your kid in the back with a baseball bat everytime he pushes the "go button" -
there's not much you can do,
the ' so called' cheap controller those brainiacs advertise there,
are (if inded the same as in the auction ...) indeed motor controllers, unfortunately rated for no more than 100 Amps,
thus the same "powerhandling" can be had for less than HALF that amount in likely MUCH better quality from kelly :(

talking of which..

Kelly:
http://kellycontroller.com/kds24200e200a12v-24v-mini-brushed-controller-p-77.html

12V 200Amps peak (120 continuous) PM controller

ideally you'd want something like this rather:
http://kellycontroller.com/kdz48303gdz24v-48v300aseparately-excited-with-regen-p-976.html
(unfortunately 24V min ...)

IDK what I can say ...
you might want to ask kellycontrollers if they have a solution for you, they might (just not listed.. or can 'convert' the PM controller I linked into a Sep Ex controller [it's not too difficult if you knwo what you're doing])
but other than that... I really don't know

'sid
 

gdeboisblanc

New member
Messages
2
Reaction score
0
Location
texas
Thank you all for taking the time to give me your advise and feedback.

The research I have found is that this motor is an replacement for one designed to pull lobster traps out of the water (not kidding).
The link below suggest that the third connection is for reverse. Not sure I trust this document but it is all I have.
Let me see if I have this right 'sid, you think that since this is a 3 wire motor, that in itself makes it necessary to need to purchase a very expensive of custom built controller.
As such I might be better off purchasing a different motor that has two connections and thus a more affordable controller can be used.
I was originally looking at a Manta II 10 hp dc motor. Is that one that is too much trouble too?

Not sure what I am going to do. Can anyone give me some things to look for when purchasing a motor that will make the controller less than say 250 or 300?

I feel like I just purchased a boat anchor!

Gregg



 

anickode

Active member
Messages
2,297
Reaction score
6
Location
S.E. Michigan
Sepex controllers essentially energize the winding full voltage and bring the field voltage up to increase torque.

It's not quite that simple, but that's in essence how it works. The actual regulated power is just a few amps on the field winding. Golf cart motors and such work in a similar way.

There's nothing wrong with such a setup, it's just different from what people are used to here.

Reverse doesn't make sense to me... But maybe? No, still doesn't make sense to me.
 

itsid

Moderator
Staff member
Messages
11,521
Reaction score
67
Location
Ruhrpott [Germany]
the beauty of sepEx motors is that you cannot just cook magnetic field strength off the ferric magnets of course, which means that a canned sealed monstrosity like that can take much higher temperatures wwithout weakening the effective motor power (until you cook off the resin from the coils of course at wich point it just fails completely ;))

Now, most if not all SpEx motor controllers just use 3 of the four lugs.

One armature lug is just bridged to one stator lug on the motor itself (to determine the "default" direction of rotation)
And likely that's just been done internally on the motor you're having there.

BUT, and that's the main issue I am having with your motor there...
it's a significant amount of current at a very low voltage,
it's just a tremendously stupid setup..
you'll need a beast of a battery (hot cranking amps in the 200amps) with an enormous capacity (think 90Ah or so) to make use of it, and even if you then have that.
MosFETS are expensive and high power mosfets even more so..
ones that can deliver a decent amount of Amperage almost automatically allow a significant amount of Voltage as well.
There is no 12V 20A MosFET I know of (plenty of 48V 20A MosFets though)
So for the same price in parts you can get 4 times the power ...
running the mosfet at a lower voltage is of course possible (up or rather down to a point)
but it doesn't make any economical sense.

So long story short: controllers for a motor like that will be rare.. one in a million rare...

12V controllers are few already (for that very reason) and there are not many 12V high power motors at all that need to be controlled (yours... that's basically it ;))
car starters can draw as much current (for huge high compression engines)
but they don't need any controller, they just need a solenoid and a on/off switch of course.

Long story short:
if you had a 4 lug sepex motor you could just run the stator coils in parallel with the armature coil,
and use any PM brushless controller (the one I linked from kelly earlier)
you'd loose the reversability if I'm not mistaking but that'd be a small price to pay IMHO.

You cannot do the same with a three lug for all I know; thus you need a controller specifically made for sepex motors.
Aaaand we're back at the dilemma with not having enough motors that any company sells large quantities (as in cheaper than custom made) controllers.

'sid

PS If you want to see me vomit over Manta motors, just do some search on diygk ;)
here's the latest iteration yes, FA made it work (again with a kelly controller) but to get there wasn't pretty (much less for him) to say the least.
No, just NO to Manta
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
the beauty of sepEx motors is that you cannot just cook magnetic field strength off the ferric magnets of course, which means that a canned sealed monstrosity like that can take much higher temperatures wwithout weakening the effective motor power (until you cook off the resin from the coils of course at wich point it just fails completely ;))

Now, most if not all SpEx motor controllers just use 3 of the four lugs.

One armature lug is just bridged to one stator lug on the motor itself (to determine the "default" direction of rotation)
And likely that's just been done internally on the motor you're having there.

BUT, and that's the main issue I am having with your motor there...
it's a significant amount of current at a very low voltage,
it's just a tremendously stupid setup..
you'll need a beast of a battery (hot cranking amps in the 200amps) with an enormous capacity (think 90Ah or so) to make use of it, and even if you then have that.
MosFETS are expensive and high power mosfets even more so..
ones that can deliver a decent amount of Amperage almost automatically allow a significant amount of Voltage as well.
There is no 12V 20A MosFET I know of (plenty of 48V 20A MosFets though)
So for the same price in parts you can get 4 times the power ...
running the mosfet at a lower voltage is of course possible (up or rather down to a point)
but it doesn't make any economical sense.

So long story short: controllers for a motor like that will be rare.. one in a million rare...

12V controllers are few already (for that very reason) and there are not many 12V high power motors at all that need to be controlled (yours... that's basically it ;))
car starters can draw as much current (for huge high compression engines)
but they don't need any controller, they just need a solenoid and a on/off switch of course.

Long story short:
if you had a 4 lug sepex motor you could just run the stator coils in parallel with the armature coil,
and use any PM brushless controller (the one I linked from kelly earlier)
you'd loose the reversability if I'm not mistaking but that'd be a small price to pay IMHO.

You cannot do the same with a three lug for all I know; thus you need a controller specifically made for sepex motors.
Aaaand we're back at the dilemma with not having enough motors that any company sells large quantities (as in cheaper than custom made) controllers.

'sid

PS If you want to see me vomit over Manta motors, just do some search on diygk ;)
here's the latest iteration yes, FA made it work (again with a kelly controller) but to get there wasn't pretty (much less for him) to say the least.
No, just NO to Manta


I think you hit it right on the head :thumbsup:

...it looks like that motor comes from the same place that sells the Manta motor

12V 3HP motor
http://www.ebay.com/itm/3-HP-12-Vol...d=331610128568&_trksid=p2047675.c100009.m1982

Manta motor
http://www.ebay.com/itm/Manta-II-10...640676?hash=item3f8654bfa4:g:F7UAAOSwRQlXdueX

Here is another that looks like it

...used for a salt spreader

http://www.ebay.com/itm/SALT-SPREAD...d=112362262089&_trksid=p2047675.c100752.m1982

It has a note:

Notes - Insulated Grd.,Offset post is the insulated ground terminal,Includes grounding cable
 

anickode

Active member
Messages
2,297
Reaction score
6
Location
S.E. Michigan
It might not work like that though.

A PM motor has a constant magnetic field for a varying input voltage to work against. With a sepex motor, applying the same varying voltage simultaneously to the exciter and armature may cause problems, such as insufficient torque at low rpms. You might wind up with a motor that will only push your kart at wide open throttle. I don't know enough about the intricacies of it to say with any certainty, but I'm pretty certain that sepex motors use a constant current with a varying voltage on the exciter to regulate the torque output of the motor.
 

itsid

Moderator
Staff member
Messages
11,521
Reaction score
67
Location
Ruhrpott [Germany]
*sigh* conveyor belt in industrial application.. maybe..
EV... nope, changing the voltage is in fact an extremely stupid idea!
You'd need a granularity that's beyond feasibility;

it's just stupid really.. ask FA about his voltage control (as adviced by the Manta guys btw...)

Anyways, EV motors are controlled by PWM switching cycles.
(full power for xy% of the time, makes xy% of the total power over the timespan)
way easier to control, far better on the efficiency and what's best... if the motor actively turns, it does so with all it's might ;)

And that holds true for sep ex motors as well.
frankly, I haven't seen many controllers that actually individually controll the exciter and the armature coils...
most just power them in series,
since the simple fact is.. that reduces the manufacturing cost for the controller by roughly half, without any noteworthy drawbacks.

So yeah... theoretically.. perhaps..
in our small patch of the world of dc motors (electric vehicles!!) though: Nope.

'sid
 

anickode

Active member
Messages
2,297
Reaction score
6
Location
S.E. Michigan
So in a situation where maintaining perfect speed regardless of load is critical. Otherwise it doesn't matter. Gotcha.
 

itsid

Moderator
Staff member
Messages
11,521
Reaction score
67
Location
Ruhrpott [Germany]
let's say "it doesn't matter much" at least ;)
IDK really if curtis uses variable excitation voltage or is just pwm the stator as it does with the armature to be honest.
either way, they too do not make a SepEx controller for 12V motors.
And they too require a four lug setup for the motors they do cover.

three lugs and we talk about a series wound motor controller again (which any sep ex can be converted to)
and that for sure throws the same voltage and amperage at the field coils as it does at the armature ;)
So yeah, since we deal with just three lugs..on that motor..

details and finesse of strictly seperately excited motors is not really important ;)

talking of which.. maybe this series controller :
http://kellycontroller.com/kdz2420012v-24v200aseriespm-p-939.html
will do the job just nicely... (shrugs) maybe the bigger one will be needed (the 300A model)
available with and w/o regen braking even.

'sid
 
Status
Not open for further replies.
Top