Bang for your buck range mods

[DIRTPIT HC]

Birmingham, I would say first, use a handheld volt meter and check the pack voltage at full charge and then each battery at full charge. That way you know for sure if the batteries are good. I just built my first cart about 2 months ago. 90 CC DS 36v resistor cart. Called ScottyB and went to 48v, 700amp controller, 400 amp sd solenoid, Hd f/r switch, digital SOC meter, high torque D&D motor10.2HP, 6 new 8v interstate batteries, 22'' tires on 10'' wheels. Did a little red neck fabrication and customization and I now have the hunting cart I wanted. Decided last weekend to see what kind of range I had. Started with a full charge 50.9v. Did 20 miles using gps with me and the wife, about 500 lbs, neither of us small. Through my neighborhood and surrounding neighborhoods. I would say mostly rolling hills with very little flat but all asphalt. Cart does 18 mph on flat. Got up to about 23 mph on some down hills. Took a little over 90 minutes, average speed was a little over 13 mph. voltage at the end of the ride after about 3 minutes rest was 49V. Stopped there because a storm was rolling in and not supposed to go below 50% SOC or 48.4v I know with mud tires at deer camp it won't do that but even 15 miles is more range than I will need.

[DIRTPIT HC]

Here is the SOC chart to go by

[JohnnieB]

Originally Posted by birmingham

1. I have a light gauge green yellow red. its like 10 bars. i am going to bring home the cart next weekend. i will be able to do some testing then.

2. I really dont see how my cart can only be doing about 7 miles on a charge and your able to get 30plus. are hills really that much worse?

3. I seem to have plenty of power its slow up the steeper hills but i expected that. it will spin the tires from a stop in gravel. unscientific but it dont think its low on power.

1. The LED Bar-Graph type battery meters lie more than most politiciansm so do yourself and your batteries a favor and get a DVM type battery meter. The one I use is near the bottom of this webpage: http://www.cartsunlimited.net/Digita...ry_Meters.html

You also need a handheld DVM is you are going to work on cart.

2. When I was running a stock controller, motor and tire with a 36V pack and 2Ga cables, I was getting a bit over 20 miles in the Mild-Hill PDS mode. That has regen braking, which improves range some.

I don't drive on level ground much, since there isn't much of it around here.

You tractor type tires may be amp hogs. What is the max inflation pressure embossed on the sidewall?

Your high current cables may have excessive resistance in them. Are any of the hot after a hard run?
They will warm up some, but if they are getting more than about 10°F above ambient air temperature, they are converting electrical energy into heat rather than motion, which in turn decreases range.

Because a PDS controller limits motor RPM by cutting back on the throttle, stock PDS carts tend not to slow as much on modest hills. Of course, once the motor RPM drops below the max allowed RPM for the mode the controller is in and the controller starts allowing the motor to draw max amps, PDS carts slow about the same as series drive carts.

3. Tractor tires may be good in plowed fields, but I'm not familiar enough with them to know how much traction the have in gravel.

------------
The batteries are 4 years old and from Sam's, so they may be a major contributing factor in the lack of range.
What is the Make/Model of the batteries?
Is the an AH rating listed on them?

The standard 36V battery pack uses 225AH batteries, and Sam's Club sell some that store a lot less energy than that.

Originally Posted by birmingham

I have a light gauge green yellow red. its like 10 bars..

say what ?

[yurtle]

I think he means an LED style volt meter that's red, yellow, green.

[birmingham]

Originally Posted by yurtle

I think he means an LED style volt meter that's red, yellow, green.

correct. i have had it in the red several times. try to keep it out of the red. i use the regen breaking, realistically how much does this really help with range? i wired up 2 switches that i can flip in different directions to make all chip forms. I have tried them all, never noticed a big difference in range. top speed is very obvious. I have replaced several of the cables, they melted. I then cleaned the battery posts and replaced the cables, 2 years ago no problems since. the tractor type tires i really dont think are that bad, i looked for a set that had constant rolling contact (they dont ride like a galloping horse) there is always rubber in contact. they really have been great. kept the smooth for the front. keep a lot of air in them.

[birmingham]

Originally Posted by JohnnieB

1. The LED Bar-Graph type battery meters lie more than most politiciansm so do yourself and your batteries a favor and get a DVM type battery meter. The one I use is near the bottom of this webpage: http://www.cartsunlimited.net/Digita...ry_Meters.html

You also need a handheld DVM is you are going to work on cart.

2. When I was running a stock controller, motor and tire with a 36V pack and 2Ga cables, I was getting a bit over 20 miles in the Mild-Hill PDS mode. That has regen braking, which improves range some.

I don't drive on level ground much, since there isn't much of it around here.

You tractor type tires may be amp hogs. What is the max inflation pressure embossed on the sidewall?

Your high current cables may have excessive resistance in them. Are any of the hot after a hard run?
They will warm up some, but if they are getting more than about 10°F above ambient air temperature, they are converting electrical energy into heat rather than motion, which in turn decreases range.

Because a PDS controller limits motor RPM by cutting back on the throttle, stock PDS carts tend not to slow as much on modest hills. Of course, once the motor RPM drops below the max allowed RPM for the mode the controller is in and the controller starts allowing the motor to draw max amps, PDS carts slow about the same as series drive carts.

3. Tractor tires may be good in plowed fields, but I'm not familiar enough with them to know how much traction the have in gravel.

------------
The batteries are 4 years old and from Sam's, so they may be a major contributing factor in the lack of range.
What is the Make/Model of the batteries?
Is the an AH rating listed on them?

The standard 36V battery pack uses 225AH batteries, and Sam's Club sell some that store a lot less energy than that.

The cheap batteries may be my entire problem. Why is there not a users manual attached to the batteries that tells you how to take care of them and how to break them in? Sell more batteries?

how much are good batteries? can the stock pds controller be used with 42 volts?

[birmingham]

how many amps does a basic stereo 2 speakers pull?

[cgtech]

Went from range to radio/amp??? Hydros also use lots of amps! Off topic?

Around 10-15 amps at peak for a modest stereo (about 5 amps average), amps & subs will be much more.

[birmingham]

Originally Posted by cgtech

Went from range to radio/amp??? Hydros also use lots of amps! Off topic?

Around 10-15 amps at peak for a modest stereo (about 5 amps average), amps & subs will be much more.

I know its a little off, i think some of my problem may be unbalanced load. i want to get a 36 to 12 converter just wandering what size converter i would need if i was running a led light bar and a stereo. i have incendecent lighting attached to 2 batteries. have been for a long time. i may need to recharge the batteries individually.