Max rpm’s admiral motor?

[JohnnieB]

Originally Posted by orangeman6

I went with the banding and the thermostat switch. For anyone else interested, his motors can be configured for speed or torque on the fly via a rotary type mechanism or a contactor. It can also be done via some jumpers on the motor itself, which is how I have mine setup for speed. I have plenty of torque that way for what I do, but I could see being able to change back and forth a good option for some people. I hadn’t heard of this before, and it wasn’t an extra charge outside of getting the switching mechanism, so I was wondering if this is something that can be done with all motors??? Mine is a series.

Dela, I think I saw in another post that you’re trying to get a new motor right away. I’d humbly suggest taking a little time and contacting Chuck. I really couldn’t believe how thorough they are. I filled out a long questionnaire about the cart and how I use it, then was sent back three pages of information on three different options. He was very helpful on the phone too.

On EMP's motor page, they state the two speed switchable designs are series motors only. http://empinc.biz/motors

The brush type DC electric motors we use consists to two sets of electromagnets. One set is stationary, called stator or field, and a moveable set called the armature. What determines if it is a torque motor or a speed motor or something in between those two extremes, is the relative strength of the two sets of electromagnets. Make the stator strong relative to the armature and it is a torque motor and make it weak relative to the armature and it is a speed motor. The magnetic strength of each electromagnet is determined by the how many turns of wire is wrapped around the magnet core, the more turns of wire, the stronger the electromagnet. The number of amps flowing through the wire also determines the strength on the magnet.

With a series motor, the same amps flowing through the armature flows through the stator, so the relative magnet strength based on amp flow remains the same regardless of the number of amps flowing through the motor. That means the relative magnetic strength of the moving and stationary sets of electromagnets is determined by the number turns of wire used to make them at the factory and the only way to change that ration is to physically add or remove the number of turns of wire in either the movable or the stationary electromagnets.

Apparently EMP winds the motor for more torque and adds a tap to the stationary sets, so when the tap is selected, the stationary electromagnet sets are weaker, leaning the motor's performance curve towards more speed.

On the other hand, the movable and stationary electromagnet set in a Sepex motor are separately excited and the amp flow isn't the same. The stationary electromagnet sets are made up from a lot of turns of wire, so not as many amps are needed to create magnet strengths similar to those found in series motors. By altering the amp flow in the stationary electromagnet sets, the performance of a sepex motor can be shifted from higher torque to higher speed during operation. It is called field mapping.


As I see it, the stator (field) electromagnet sets are not tapped in sepex motors due to a couple reasons. First and foremost, no need to do so since it is already being done electrically. (Field mapping) Secondly, I don't know of any controller out there that can switch between two different field maps.

[Dela]

Originally Posted by JohnnieB

I'd give Chuck at EMP a call. He'll design a motor to fit your needs/desires and do high speed banding if you want to spin it fast.
http://empinc.biz/

Can't say enough about Chuck at EMP.. He is the Doc Brown of golf cart motors.. his knowledge blew me away.

I've got a rebuilder working on my toasted motor now, he thinks he can repair. but from what Chuck said - I may go that route anyway.. dude knows his poo poo

[scottyb]

We told you so

[noxin]

So my previous questioning on upgrading a series motor (upgraded cart from 36v to 48v) got a lot of votes for Plum Quick -- is EMP a better choice?

[scottyb]

Originally Posted by noxin

So my previous questioning on upgrading a series motor (upgraded cart from 36v to 48v) got a lot of votes for Plum Quick -- is EMP a better choice?

It depends upon what you want and what you want to spend. PQ, Admiral, FSIP, D&D all offer off the shelf upgrade motors. EMP offers custom solutions at a higher cost.

[noxin]

Originally Posted by scottyb

It depends upon what you want and what you want to spend. PQ, Admiral, FSIP, D&D all offer off the shelf upgrade motors. EMP offers custom solutions at a higher cost.

I definitely won't say the cost is irrelevant, but if it's the difference between $500 and $800 I would definitely just go with the better option.

If we get over $1000......

[orangeman6]

Chuck wrote up three different options for me. All three very detailed. I’ve got a 58v lithium pack on a street cart. I knew the speed would be there, and didn’t have big torque concerns, so went with what we thought would be the most robust. All three motors would have ended up within $50 of each other by the time options were added. My invoice was $675. That included a $200 core charge, which I got back $110 of. I’m in California, so shipping motors each direction added up a bit. The $675 also included $50 for the high speed banding and the same for the over temp switch.

I’m sure I could have gotten a great motor at one of the other places, but Chuck was the one that took the time to try and get me exactly what I needed.

Hope this helps.