Alltrax XCT upgrade?!

[scottyb]

Right. ^^^ What he said exponentially
Also don't over look the 42v option

[tankdogg60]

Originally Posted by JohnnieB

Depends on which solenoid you have, the Super-Duty (400A/1000A) Scotty sells, works at 36V, 42V and 48V, but most, if not all, of the others are voltage specific.

Also, a 470Ω resistor is used with a 48V battery pack rather than a 250Ω, but the XCT doesn't use a pre-charge resistor, so that's a moot point.

Going from 36V to 48V increases both torque and speed by 33.3%, so the motor will run "better". As for "cooler", it depends on how heavy your foot is with all the newly found power.

Technically, a motor coverts watts of electrical energy into foot/pounds of mechanical torque. Since Watts = Amps X Volts, if you increase the voltage, it takes fewer Amps to produce the same number of Watts. The amount of heat generated decreases exponentially as the number of Amps through the motor decrease, so the motor does run cooler at 48V than it does at 36V when the same amount of torque is being produced.

I truly appreciate your time and explanations on these threads! Your knowledge helps me tremendously and I am very grateful for all the help!

[tankdogg60]

Originally Posted by scottyb

Right. ^^^ What he said exponentially
Also don't over look the 42v option

What would I need for 42V? Just another battery? Charger?

[scottyb]

Originally Posted by tankdogg60

What would I need for 42V? Just another battery? Charger?

Yep. That's what Johnnie and I are running.
I currently have two PDS carts. 42v one with DCX400 and other with XCT400

[tankdogg60]

Originally Posted by scottyb

Yep. That's what Johnnie and I are running.
I currently have two PDS carts. 42v one with DCX400 and other with XCT400

48V charger will work?

[scottyb]

42v charger needed. We are using DPI 42v. The stock (bandit too) motor is happier on 42v than 48 in my experience

[tankdogg60]

Originally Posted by scottyb

42v charger needed. We are using DPI 42v. The stock (bandit too) motor is happier on 42v than 48 in my experience

Awesome, I really appreciate all of your time!

[timmyjane]

Why 42 over 48?

[Revolution]

Originally Posted by timmyjane

Why 42 over 48?

Thats a good question. Its a question that needs some explanation from a motor designer to answer, or real world experiences from fellow cart enthusiast.

I like to push the limits, both of my carts are 72 volts. I use them on a daily bases and drive them like I do my cars and trucks, they don't see full throttle everyday but when I put the peddle to the metal I expect some response!

I have no need for the extra power, so its just there for fun. The extra watts may well kill my motors faster than the normal 36V or 48V would, but I only use it every now and then.

42 volts most likely means no loss in motor life, with a good performance increase, best of both worlds!

[JohnnieB]

Originally Posted by timmyjane

Why 42 over 48?

It depends on the needs, wants and desires of the cart owner as well as what the cart is used for.

My wife and I use our cart as a NEV (Neighborhood Electric Vehicle), plus yard work and some mild off-road stuff. We have hilly terrain and in its stock form our PDS was a bit wimpy, so I installed a DCX400, which gave me 24 MPH on the roads at 36V with stock height tires and enough low end torque to drag fairly good sized fallen branches to the burn pile.

What it didn't give us was enough run-time to drive to our favorite shooting range and back on a single charge. I wanted to keep everything under the seat and couldn't get the run-time I needed with a 48V pack made up of six 8V batteries, so I went with seven 245AH 6V batteries. My goal was run-time, but I gained speed and torque also.

Technically, if the tires height is stock (18"), 42V will spin a stock PDS motor at about 6,500 RPM, which is about as fast as any cart motor ought to be spun for extended periods of time, unless the motor is specifically designed for higher RPM. Motors in PDS carts with tires taller than stock tend not to over-rev at 48V because taller tires take more torque to spin, so the motor won't reach the same RPM as it does with stock height tires.

The local ordinances governing which roads golf carts can be driven on, changed last year and I can no longer drive my cart to my favorite shooting range legally, so I no longer have the need for an extended run-time and will most likely go to six 8V batteries (48V) when I have to replace the batteries since the XCT controller I now have, allows me to limit the max motor RPM. 6,500 RPM on my 17" tall tire will give me 26.5 MPH, which is more than enough for my purposes and the cart will slow even less on the steeper hills around here.

Bottom line: 42V is the best option for some applications, but not for all applications. Performance-wise, it is better than 36V, but not as good as 48V. It is up to the cart owner to weigh the pros and cons and make the choice.