Does such a chart exist?

[sleepyluke]

I am in the market to upgrade the motor controller set up on my cart. I know there are a ton of combinations, but searching has made my head spin with the slightly, little better, much better, ton better, lots more, words to describe what an upgrade will do. I know that alot is subjective, but in theory does a 400 amp controller give you 33% more torque over a 300 amp? With a motor upgrade can you combine the numbers? Or is it literally a case by case basis and jsut jump in and see what you like? I fully admit I am cheap and don't want to spend any more than I ahve to, but I also don't want to be into an upgrade for $700 and really not be able to tell much over stock set up that $800 would have pinned my head against the seat and given me more than I ever realized I wanted. And yes I fully expect whatever I end up with needing that little more on the next cart, but I actually plan to keep this one over a year (we will see how that works out too!)



Having said that, when really putting a number to it, will 10% upgrade in torque cancel speed decrease on a hill, spin the tires, or not be able to tell anything? 50% I really don't know


Hope this makes a little sense

[gornoman]

Let's start by giving us the current specs of the cart, as well as the future plans and usage of the cart.

[88 ez go]

Contact Scotty B on here he will hook you up answer your questions and point you the right direction.

[sleepyluke]

Well unfortunately ScottyB is part of my problem!! I talked to him a good bit and I think he has me with too many options. I am not looking for a tree climbing monster (yet) but don't want to do something that a different combination / little more would have done better.

My current version of reality is that I am going to go with a Bandit motor and 400 amp controller from ScottyB, with the distant future version to think about going to 48 volt when the batteries die. Scotty has helped me a ton, but with all the combinations that are out there and this version will give you alot more power vs a little more power, from person to person may be the exact same increase. I have looked at the controller with stock motor combo, looked at the PQ motors, looked at the EMP motors, and combinations of all of the above.


I am looking to climb the hills around my house better, and if someone jumps on the back and wants to ride, I want to be able to make it up the hill without telling them to get off. Other than that, my deer camp is mainly flat but a few smaller hills and can be muddy, but I am not looking to bury the cart on a regular basis, but do enjoy running the gravel roads.

If anyone does ever create such a chart, I will put my gains into it!!!

Should the gains be literally this increase plus the other increase? Say a motor gives 20% increase and a 400 amp controller is 33% more than the 300 giving a 59.6% increase? (1.2 * 1.33) or 53% increase 1.2 + 1.33? Either way is pretty significant to me and worth doing.

But I did build my 2 gauge cables last weekend and drove by a Holiday Inn Express, so I am good to go for a day or 2.....

[scottyb]

Most people use a 500 amp control for what you want to do.
Somebody correct me if I'm wrong but I thought the PQ bandit is not meant for hill climbing. I read It will give you new bearings & brushes with 2-3 mph more speed. Speed and torque are always a trade off.
Running the stock motor on 48v is the biggest bang for the buck initially. You didn't scrimp on the wires, so why scrimp on the control? If you are torn between the 4 and 500 control try the 475 max amp output of the SPM48400 (pkg 484) go here > Pkg. #484 SPM48400

[JohnnieB]

I'm confused. Isn't the PQ Bandit a Sepex motor and the SMP48400 a Series controller?

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Regardless, because each percentage of gain/loss is based on changing only one variable, they will not add linearly when two (or more) variables are changed. You also get into a gray area of mathematics when multiplying or dividing a percent by a percent.

The total % gain/loss has to be the before number subtracted from after number and the resulting number divided by the before number

Without a dynamometer, the actual torque gains cannot be accurately measured , but for changing the ampacity of the controller and/or the voltage of the battery pack, Killo-Watts delivered to the motor can be used as a yardstick for comparisons. Of course, how much torque the motor actually produces with the resultant amount of energy delivered to it, depends on the efficiency of the motor.

If the original controller was 300A and the original battery pack was 36V, it will deliver 10.8kW to the motor.
Only changing to a 400A controller will deliver 14.4kW (+33.3%)

Only changing to a 48V battery pack will deliver 14.4kW (Also +33.3%)

However, changing to both a 400A controller and a 48V battery pack will deliver 19.2kW, which is a 77.8% gain instead of 66.7%.

[MDLNB]

Taking all that into consideration, I wonder why I realized NO increase in speed when I upgraded from a 225 amp controller to a 400 amp controller. I may have noticed a very minute increase in take off, just a slight increase. It seems like I go up inclines about the same speed as before the upgrade. Don't get me wrong, I do get 19mph on this old series cart, but I thought I might get a bit more out of the upgrade. I also put 4ga battery cables in. Guess that is all I can hope for without trading in my motor for an upgrade.

[scottyb]

A Bandit reworked motor can be Sepex or Series, whichever you have. Series carts do not increase in speed with more amperage. They simply use the increased amperage to make more torque. The loss from big tires can be greater than the increase in torque gains from 275 to 400. The bigger controllers are a safer bet for increased performance when you are trying to regain loss torque and get a noticeable increase. All electric carts slow down under load, how much depends on about 10 factors but, boils down to an equation of demand, supply, and delivery.

[sleepyluke]

Thanks for the help and MDLNB is exactly what I was worried about. I keep leaning more toward the 500 amp controller, but there seem to be a good amny more people on here including Johnnie that have the 400 and seem more than pleased (with other combinations as well). And per PQ guys, they can do the Bankdit motor in either the Sepex or series and roughly 20% increase in speed and torque.

Johnnie, that is what I was looking for, I thought I had a chart of sorts built to caculate that, but my numbers were off, and not sure where my error was so I deleted it hoping to find something that I did not build to figure it.

[as350pilot]

For the extra little bit of money I would go with the 500amp. Either way you will be pleased.