What to expect with 500 amp controller and Stock Motor

[cgtech]

Absolutely.

[JohnnieB]

Several of variables come into play when you change controllers and tires sizes of PDS carts and the number of variables increase drastically when changing pack voltage and changing motors are also thrown into the mix.

It makes my head swim and, for the most part, I've been there and done that.

Nothing said has been wrong, but some of the inferred comparisons border on comparing apples to oranges, or perhaps oranges to tangelos would be a better description.

When comparing cart motors built in the same sized housings, they can be wound for high speed (more high end torque actually) or High torque (more low end torque) or something in between. However, when going from the relative short housing of a stock PDS motor, to the longer housing of an aftermarket motor, both low end torque and high end torque can be gained.

What I'm saying is the my aftermarket motor, which is a couple inches longer and about 10 lb heavier and is considered to be wound for high speed, has significantly more low end torque than the stock PDS motor it replaced.

Granted, I did go from a 400A controller to a 500A controller at the same time, but the increase in torque felt far more than just 20%.

[scottyb]

Oh yeah? Well, I had a pink grapefruit and a red orange once.

[UFGators]

These are all good points! So is the consensus to buy the 500amp controller and hd solenoids if I have any idea that I may upgrade the motor in the future or am I splitting hairs?

[HiTechRedNeck]

We can compare oranges to Steak and throw in upgrade to RXV

[JohnnieB]

Originally Posted by UFGators

These are all good points! So is the consensus to buy the 500amp controller and hd solenoids if I have any idea that I may upgrade the motor in the future or am I splitting hairs?

This is my personal opinion and other may disagree: You can turn a DCX500 down to 400A and run a stock PDS motor, but you cannot turn a DCX400 up to 500A to get more oomph out of a more robust motor.

That said, the only place you'll notice the difference between feeding a more robust motor with a 400A controller and a 500A controller is accelerating from a standstill and when bogged down to a crawl on a steep hill.

The thing to understand is that the controller does not force amps through the motor. Instead, it limits the amps the motor is allowed to draw and the number of amps a motor will draw when unfettered by outside limitations, is determined by the RPM the armature is spinning at.

In a nutshell, once the motor's RPM exceeds a few hundred RPM, it simply cannot draw more than 400A even if the controller was capable of passing 500A (or 10,000A) to it. The laws of physics won't allow it.


On the other hand, the DCX500 case is longer than the the case of the DCX400. so it has better heat dissipating abilities. And it is slightly more efficient, so it doesn't heat up quite as much during hard use.

You are planing on tires that are at the upper end of the height spectrum typically used on golf cart, so my vote is for the DCX500.

As for solenoids, the 48V Super-Duty (400A/1000A) is the one to buy. It'll handle any controller and motor combination you are likely to install in your cart and runs at anything from 36V to 48V, so you don't have to replace the solenoid if you decide to up the pack voltage. I've ran the one I have at both 36V and 42V, with DCX400 and DCX500 controllers and stock PDS and aftermarket motors.

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You can sink a sizable chunk of change in a cart, so some hairs need to be split.

[cgtech]

I agree totally with the above statement. But, you can certainly use a upgraded motor on a DCX400.

[Knothead]

Originally Posted by cgtech

I agree totally with the above statement. But, you can certainly use a upgraded motor on a DCX400.

But it won't perform like the same upgraded motor on a DCX500.....

[JohnnieB]

Originally Posted by cgtech

I agree totally with the above statement. But, you can certainly use a upgraded motor on a DCX400.

Absolutely. Had it not been for his plans to go to 23" tall tires, I would lean more towards the DCX400.

Even with the tall tires, what pushes me towards the DCX500 isn't so much the additional amperage as it is the larger heatsink area.

Originally Posted by Knothead

But it won't perform like the same upgraded motor on a DCX500.....

That is true, but the difference in performance is only in the lower RPM range.

At some RPM, a DC motor cannot draw more than 400A, so at any RPM above that, the difference in performance between a DCX400 and a DCX500 is more or less nil.

Or at least that is true for Series wound motors. With Sepex motors, the number of amps flowing through the the armature is additionally dependent on how many amps are flowing through the field windings as well as the RPM the armature is spinning at, so the specific RPM at which a Sepex motor cannot draw more than 400A, depends on the field current at the time. With 20A of field current, my motor draws 400A of armature current at 1450 RPM, but the DCX family of controllers will allow up to 30A of field current and that RPM number might be lower with more field current.

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Ironically, due to the tiny turf tread tires I'm running, I've almost got too much low end torque.

Of course, with taller tires and/or a more aggressive tread pattern, it would be less of an issue.

[jackman08]

Wow, that may be to much info at one time for me. If I am understanding you right Johnnie B. I wasted my money buying a 500+ controller for a series cart instead of a 400 amp.? BUT now that I have it anyway, are you still sold on the rapter AMD 7126? Is there anything else out there that would give me that type speed for someone that is financially embarressed? If not, I guess I can go rob my local 7-11!!!!

A man and his money will soon depart