lifted club cars - lifted ezgo
Home FAQDonate Who's Online
Go Back   Buggies Gone Wild Golf Cart Forum > Golf Cart Repair and Troubleshooting > Electric Club Car
Electric Club Car Electric DS, and Precedent golf cars



Post New Thread  Reply
Thread Tools Display Modes
Unread 09-12-2014, 12:56 AM   #1
Not Yet Wild
 
Join Date: Sep 2014
Posts: 3
Default What are the volt reading for 6 volt batteries under load

I just picked up a 1986 ds and not sure if the batteries are any good i get the normal 6.4 after waiting a few hours after charge then i hook the cart to a post and pressed the pedal all the way down and under load and i get a numbers around 5.5 to 4.8 is this normal, also while charging when checked they are 7.4 then when you unplug the charger they are 6.8 then 15 mins later 6.6 but after few hours they settle in at the 6.4 range
sreams11 is offline   Reply With Quote
Alt Today
BGW

Golf car forum Sponsored Links

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum
   
Unread 09-12-2014, 12:58 AM   #2
Cartsunlimited.net
 
scottyb's Avatar
E-Z-GO
 
Join Date: Dec 2007
Location: Southern California
Posts: 64,083
Default Re: What are the volt reading for 6 volt batteries under load

Quote:
Originally Posted by sreams11 View Post
I just picked up a 1986 ds and not sure if the batteries are any good i get the normal 6.4 after waiting a few hours after charge then i hook the cart to a post and pressed the pedal all the way down and under load and i get a numbers around 5.5 to 4.8 is this normal, also while charging when checked they are 7.4 then when you unplug the charger they are 6.8 then 15 mins later 6.6 but after few hours they settle in at the 6.4 range
5.9 is what I like to see the battery hold under a 300a load. More drop than that indicates a weak cell or worse.
scottyb is online now   Reply With Quote
Unread 09-12-2014, 01:28 PM   #3
Gone Wild
 
Join Date: Oct 2009
Posts: 406
Default Re: What are the volt reading for 6 volt batteries under load

What you describe sounds normal. SOC (state of charge) voltages are completely useless and meaningless on an operating system. SOC voltages only apply on a battery that is fully rested and disconnected from any load or charge. And even then they are only ball park. There is only one way to determine the true SOC of a battery and that is with a lab quality temperature compensated hydrometer. But even with a hydrometer it does not tell you the capacity.

For any Trojan flooded lead acid (FLA) battery SOC voltages at room temp are:

100% = 2.122 vpc or 6.37 volts on a 6 volt battery
50% = 2.017 vpc or 6.05 volts on a 6 volt. Don't go below 50%

As for voltage sag is very hard to answer because there are a lot of variables, most importantly Internal Resistance aka Ri. A new T-105 that has had a few cycles, at room temp, at 100% SOC will have a Ri = approx .005 Ohms. That does not sound like much but is significant. Voltage = Current x Resistance.

Cruising at normal speed on a flat surface will draw roughly 50 to 60 amps on the batteries. So if we have a 6 volt battery at 100% SOC with a 50 amp load we will see the voltage sag from 6.37 volts - (50 amps x .005 Ohms) to 6.12 volts. Using Scotty's example of 300 amps or starting current of 300 amps you will sag from 6.37 volts down to 4.87 volts on a new fully charged battery.

As the battery ages or SOC decreases battery Ri goes up, thus more voltage sag and power loss. Eventually all batteries Ri goes up to a point where the battery will no longer take or supply a charge. When you connect the charger on a dead battery it trips off very quickly because the charge ris fooled into thinkng the battery is fully charged up. You measure the voltage and it reads good with no load. Then you step on the accelerator and nothing happens and you see the battery voltage dives toward ZERO.. Take your foot off and the voltage jumps back up to normal. You know it is time for new batteries.

FWIW you now know why AGM and Lithium batteries perform better because they have significantly lower Ri than FLA batteries. A 6 volt AGM 220 AH battery has an Ri of approx .0007 to .002 Ohm's depending on the manufacture. That same 300 amp start up current sags the voltage down from 6.37 volts to only 6.37 - (300 amps x .0007 Ohms) = 6.16 volts compared to 4.87 volts for a flooded Trojan.
sunking is offline   Reply With Quote
Unread 09-12-2014, 02:35 PM   #4
Not Yet Wild
 
Join Date: Sep 2014
Posts: 3
Default Re: What are the volt reading for 6 volt batteries under load

i took it out to campground today after it sat all night the batteries were 6.37 and while riding the battery would drop to low 5's then steady out to the 5.7 range also after driving a good while the curtis gauge dropped 2 lines and the volts were 6.17 then they climbed while sitting i think maybe next year just replace batteries thanks for the replies so fast
sreams11 is offline   Reply With Quote
Unread 09-12-2014, 03:43 PM   #5
Moderator
 
rib33024's Avatar
E-Z-GO
 
Join Date: Apr 2009
Location: FT Lauderdale FL.
Posts: 13,169
Default Re: What are the volt reading for 6 volt batteries under load

If the wheels and tires are not spinning when you push the go pedal to the floor, you are going to burn up the motor or controller or melt a battery post or a fire. Never stall the motor with the pedal to the floor





Quote:
Originally Posted by sreams11 View Post
then i hook the cart to a post and pressed the pedal all the way down and under load
rib33024 is online now   Reply With Quote
Unread 09-12-2014, 04:47 PM   #6
Gone Wild
Yamaha
 
Join Date: May 2012
Location: Rio Verde, Az
Posts: 2,684
Default Re: What are the volt reading for 6 volt batteries under load

Yikes! Good way to kill your motor.
Volt_Ampere is offline   Reply With Quote
Unread 09-12-2014, 08:29 PM   #7
Not Yet Wild
 
Join Date: Sep 2014
Posts: 3
Default Re: What are the volt reading for 6 volt batteries under load

i did it in moderation while i had it tied up to check the load but ya it got hot so i stopped the hooked up way and drove it and tested it on the move
sreams11 is offline   Reply With Quote
Reply

Tags
6v batteries under load
Go Back   Buggies Gone Wild Golf Cart Forum > Golf Cart Repair and Troubleshooting > Electric Club Car


Thread Tools
Display Modes


Similar Threads
Thread Forum
90 ezgo getting 36 volt reading between hot to switch and load side Electric EZGO
placement when adding 2 more 6 volt batteries to 36 volt for 48 volt conversion Electric Club Car
1990 Club Car DS 36 volt to 48 volt conversion fitting batteries question Electric Club Car
Volt reading when Isolating 2 6v batts, is seperate volt meter needed? Electric EZGO
New Batteries and Volt Reading HELP Electric Club Car


All times are GMT -5. The time now is 12:29 PM.


Club Car Electric | EZGO Electric | Lifted Golf Carts | Gas EZGO | Used Golf Carts and Parts

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.