Just bougth an 8KW dc motor
- Thread starter Njay
- Start date
Ariane
10 kW
Hi,
This motor is an Etek Motor but it didn't like new i think that Manta motor are rebuiding them did you buy this one on ebay and you can find the specs with this link.
http://cgi.ebay.com/DC-Motor-12-24-48-Volt-Etek-MT-Pattern-Permanent-Magnet-/250714492476?pt=LH_DefaultDomain_0&hash=item3a5fbf8e3c
Good day!
Black Arrow
This motor is an Etek Motor but it didn't like new i think that Manta motor are rebuiding them did you buy this one on ebay and you can find the specs with this link.
http://cgi.ebay.com/DC-Motor-12-24-48-Volt-Etek-MT-Pattern-Permanent-Magnet-/250714492476?pt=LH_DefaultDomain_0&hash=item3a5fbf8e3c
Good day!
Black Arrow
Yes, I bought it on ebay, but the sale says it's new (quoting: "New: A brand-new, unused, unopened and undamaged item in original retail packaging (where packaging is applicable)."). It doesn't seem new nor unused nor undamaged to me at all, but since it's the first time I have a motor of this power in my hands, I thought of coming here for some 2nd opinions.
But there's more which the pics don't show. In some places I've seen some kind of a "dirty grease" between 2 consecutive coils, which I suppose don't help cooling. And they sent me the motor "upside down", that is, with the rotor facing down, the heavier part on the top; they glued the address on the "bottom" of the box and it traveled upside down, the top styrofoam was completely ruined since it wasn't designed to carry the weight of the motor - even less supported on the rotor (foam is even cracked at the center, due to rotor pressure).
But there's more which the pics don't show. In some places I've seen some kind of a "dirty grease" between 2 consecutive coils, which I suppose don't help cooling. And they sent me the motor "upside down", that is, with the rotor facing down, the heavier part on the top; they glued the address on the "bottom" of the box and it traveled upside down, the top styrofoam was completely ruined since it wasn't designed to carry the weight of the motor - even less supported on the rotor (foam is even cracked at the center, due to rotor pressure).
Ariane
10 kW
Njay,
You need to check with your seller on EBay for his explanation about it. It's really hard to tell you from picture I think this motor is a "rebuild" motor from them ( Manta) so the appellation "new" is partially incorrect and correct at the same time.
For the packaging the original foam from ETEK (Briggs and Stratton) was not stiff enough and can be broke during transport, I have received an Etek many years ago with a broken package but the motor was ok.
If the seller didn't want to help you, you can check for brush wear on the motor is another sign for a new or old motor. Also if you are able to turn the shaft by hand is good sign of the health of this motor.
For the grease if this motor is rebuild is probably normal but I can't certify this other member here can help on that one.. At the end after you check the point I have mentioned above you can try to powering (no load speed) with a fuse and try to operate this motor a low voltage (24 Volt) or higher with you controller to see if this motor seem to operate adequately in the worst case you will just blow out a fuse. If your motor seems to work great after that I don't bother and I think that you can use it with your project.
A Mars Motor ME0708 (brush) will be brand new for sure but this motor weight 30 pounds and is really bigger and heavier than your motor for about the same power. The other option from Mars is their M909 weight about the same but seem to have slightly less power than your motor and it's big as the ME0709 (size) the others brush motor from Mars are heavier and bigger, if you bought a brushless motor for Mars (lighter about the same as your motor) you need a brushless controller (expensive) to use it's power.
Good day!
Black Arrow
You need to check with your seller on EBay for his explanation about it. It's really hard to tell you from picture I think this motor is a "rebuild" motor from them ( Manta) so the appellation "new" is partially incorrect and correct at the same time.
For the packaging the original foam from ETEK (Briggs and Stratton) was not stiff enough and can be broke during transport, I have received an Etek many years ago with a broken package but the motor was ok.
If the seller didn't want to help you, you can check for brush wear on the motor is another sign for a new or old motor. Also if you are able to turn the shaft by hand is good sign of the health of this motor.
For the grease if this motor is rebuild is probably normal but I can't certify this other member here can help on that one.. At the end after you check the point I have mentioned above you can try to powering (no load speed) with a fuse and try to operate this motor a low voltage (24 Volt) or higher with you controller to see if this motor seem to operate adequately in the worst case you will just blow out a fuse. If your motor seems to work great after that I don't bother and I think that you can use it with your project.
A Mars Motor ME0708 (brush) will be brand new for sure but this motor weight 30 pounds and is really bigger and heavier than your motor for about the same power. The other option from Mars is their M909 weight about the same but seem to have slightly less power than your motor and it's big as the ME0709 (size) the others brush motor from Mars are heavier and bigger, if you bought a brushless motor for Mars (lighter about the same as your motor) you need a brushless controller (expensive) to use it's power.
Good day!
Black Arrow
BlackA, thanks a lot for your good advice.
Yes, I've been checking and these are indeed "remanufactured" (whatever that means exactly), but the seller's auction mentions "New". Negative point to him.
I inspected the brushes and they all seem new, long (~20mm from tip to the wear mark) , all same length.
The rotor I have tested before for slacks, and there seems to be no slacks at all (no side slacks, no in-out slacks).
I tested it with no load at 11.5V with a car fuse; it instantly blows a 10A fuse at power-on (not strange) but with a 15A one it runs ok. I currently only have a DMM to measure the "idle" current, and it reads around 4.2A, but the internal resistance of the DMM is limiting the current (motor slows down when switching to the DMM), the real reading should be maybe 20%-40% more.
It does, however, seem to have a vibration, as if the rotor has one point where it passes with a bit more resistance when rotating. I cannot feel this point if rotating it by hand, by hand all seems normal. What could this be, rotor imbalance, bad bearing, one of the brushes, a bad collector, ...? I'm going to check the copper at the collectors and the brushes surface.
I wasn't aware that this motor really was "Lynch" technology, uooouuuuu...
p.s.: I had a lot of fun trying to rotate the motor while it spins
Yes, I've been checking and these are indeed "remanufactured" (whatever that means exactly), but the seller's auction mentions "New". Negative point to him.
I inspected the brushes and they all seem new, long (~20mm from tip to the wear mark) , all same length.
The rotor I have tested before for slacks, and there seems to be no slacks at all (no side slacks, no in-out slacks).
I tested it with no load at 11.5V with a car fuse; it instantly blows a 10A fuse at power-on (not strange) but with a 15A one it runs ok. I currently only have a DMM to measure the "idle" current, and it reads around 4.2A, but the internal resistance of the DMM is limiting the current (motor slows down when switching to the DMM), the real reading should be maybe 20%-40% more.
It does, however, seem to have a vibration, as if the rotor has one point where it passes with a bit more resistance when rotating. I cannot feel this point if rotating it by hand, by hand all seems normal. What could this be, rotor imbalance, bad bearing, one of the brushes, a bad collector, ...? I'm going to check the copper at the collectors and the brushes surface.
I wasn't aware that this motor really was "Lynch" technology, uooouuuuu...
p.s.: I had a lot of fun trying to rotate the motor while it spins
Ok, I'm going to return it. I've checking more carefully the rotor and I can now find with my hand a point where the rotor makes a kind of a "bass click" when changing rotation direction, a kind of a tiny backslack, which probably means a bad bearing.
RocketmanIII
1 µW
- Joined
- Jul 9, 2015
- Messages
- 1
Don't get too hasty. First how much did you pay for it? If you bought it at a cheap price let's say $200.00 or less I would keep it and fix it, but if you paid premium price say $300.00 or more, yes return it. This of course is if you feel you are handy at fixing things that are repairable or like the challenge.
SlowCo
1 MW
RocketmanIII said:
At least you weren't too hasty replying more than 4 years and 8 months after the last post...
:lol: 
John in CR
100 TW
SlowCo said:RocketmanIII said:
At least you weren't too hasty replying more than 4 years and 8 months after the last post...
I guess he's a 3rd generation xerox copy of Rocketman.
