|
Electric golf carts Harley Davidson, Melex, Pargo, Taylor-Dunn and other Misc. Carts. |
|
Thread Tools | Display Modes |
02-03-2009, 10:22 PM | #1 |
just hangin' around
Join Date: Jan 2009
Location: Oxford Flo-Rida
Posts: 1,102
|
What Volt specs. from a 48V setup
Could you guys tell me what voltage readings I should be getting from a set of six new 8V batteries. At full charge what should the pack read, what should each individual battery read, and also what voltages should I see from pack while running....would this change being full throttle up hill and also on flats. Im asking because I want to be sure Im getting full charge and don't have a bad battery in the pack...They are Wal-mart Golf Cart batteries made by Johnson Controls. I also have a 48V Schauer charger and I want to know it is charging fully also.
Thanks everyone |
Today | |
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 |
|
02-03-2009, 10:37 PM | #2 |
Happy Carting
Join Date: Dec 2007
Location: Southern California
Posts: 73,358
|
Re: What Volt specs. from a 48V setup
THese stats are taken from the Trojan website... 100% charged is 50.93 volts. Divide by 6 = ? individual reading... New batteries will not reach their highest potential until 10 to 20 charge/ 50% drain cycles. 50% drain reading is 48.41. NEVER draw the pack down below 48v..... Good luck.
|
02-03-2009, 11:03 PM | #3 |
just hangin' around
Join Date: Jan 2009
Location: Oxford Flo-Rida
Posts: 1,102
|
Re: What Volt specs. from a 48V setup
Scotty, your always there with the answers..Thanks
I went\ to Trojan and grabbed all the specs..took a second to find them My next question, probably sound silly to you but... I understand those voltages they listed...said open circuit which I assume means while standing still, no throttle. Should I be watching any voltage readings while on the throttle to test the battery pack? |
02-03-2009, 11:22 PM | #4 |
just hangin' around
Join Date: Jan 2009
Location: Oxford Flo-Rida
Posts: 1,102
|
Re: What Volt specs. from a 48V setup
|
02-04-2009, 09:51 AM | #5 | |
Gone Wild
Join Date: Nov 2008
Posts: 240
|
Re: What Volt specs. from a 48V setup
Quote:
The SOC are only relative and do not indicate capacity. To take SOC measurements under a load like driving, you need to have a hydrometer to sample/monitor the specific gravity. When you see the SPG = 1.90, measure the voltage uder load and that will be the true 50% SOC for your battery. 100% = 1.255 - 1.275 75% = 1.215 - 1.235 50% = 1.180 - 1.200 25% = 1.155 - 1.165 0% = 1.110 - 1.130 Under load your 50% SOC reading should be around 46.32 volts at 25 degree C |
|
02-05-2009, 09:31 AM | #6 |
just hangin' around
Join Date: Jan 2009
Location: Oxford Flo-Rida
Posts: 1,102
|
Re: What Volt specs. from a 48V setup
OK so I have the meters, I have the understanding and ability...now I need some specs. Taking off from a dead stop or climbing a hill, what would be the minimum voltages I would want to see from good batteries. When it warms up tomorrow, I want to do a battery voltage "balance" test for all batteries and check each batteries minimum voltage under load like, that up hill from a stop idea...that would point to a bad battery or cell also wont it?
If I still had my load tester this would be easy, but I don't so i was thinking of straining cart and measuring each batteries min/max readings under the same stress(hill). I will also do a voltage drop test across main cables running all the way back to the motor. I was just thinking about a bad contact somewhere in the VGlide controls f/r switch or maybe my soldered joints. WHat would be considered a bad voltage drop reading across my test from batt+ to motor stud...any thoughts? thats enough typing for now |
02-05-2009, 10:01 AM | #7 |
Gone Wild
Join Date: Nov 2008
Posts: 240
|
Re: What Volt specs. from a 48V setup
As I tried to explain State of Charge voltages are only valid when the batteries have been at rest for several hours. The only way to use voltages under load is to use a hydrometer, and record the voltages.
I just checked Trojan specs again and it looks like they changed them slightly. 100% 1.277 90% 1.258 80% 1.238 70% 1.217 60% 1.195 50% 1.172 So get you a hydrometer, fully charge the batteries until you get a SP of 1.277, take off and record voltage, drive in 10 minutes intervals, stop and check the hydrometer readings and record the voltages at the measurements above. When you take the voltage the cart should be running. If you are looking for a magic number it is 50%. You never want to discharge more than that, and that voltage should be around 46.4 volts. What you actually get will be slightly different. Hydrometer is the only acurate measurement of the batteries health and state of charge. Good Luck Edit: take the voltage right at the battery terminals, or else you will have a voltage drop error. |
02-05-2009, 10:10 AM | #8 |
Happy Carting
Join Date: Dec 2007
Location: Southern California
Posts: 73,358
|
Re: What Volt specs. from a 48V setup
I don't know the answer to all that .... but, you can get a hydrometer at any AutoParts store for like 7-15 dollars that will test the specific gravity of each cell .... and that will tell the exact condition of each battery cell.
|
02-05-2009, 11:11 AM | #9 |
just hangin' around
Join Date: Jan 2009
Location: Oxford Flo-Rida
Posts: 1,102
|
Re: What Volt specs. from a 48V setup
I might just go buy one of those..have read several posts while searching these forums and posts referring to hydro readings also...its cold and I have nothing better to do...
Also I plugged my charger back in this morning and turned it on..it started charging at 59.9 volts...then it went to its other charge mode within an hour and now putting out 53.* volts, and its been there for a few hours.....normal?? |
02-05-2009, 11:49 AM | #10 | |
Gone Wild
Join Date: Nov 2008
Posts: 240
|
Re: What Volt specs. from a 48V setup
Quote:
One note here though, temp affects SP and volatge. The numbers I gave you are for 25 C or 77 F. Best to wait for a warm day, or if you are good at math you can adjust for temp compensation is colder. I can help you if you want to do that. Its not that hard, just takes time. But if you are good with Excel you can do it quick and make a chart for every dergree off of 77. Just be sure you buy a quality Hydrometer, accuracy counts. Get the kind that looks like a turkey baister with a float. Avoid the ones with colored balls. Temperature Correction: SG of acid is temperature dependent. If the temperature is very cold or very hot this can lead to incorrect readings. To correct for temperature use the following equations the equations or below 70ºF subtract points (0.03 per 10ºF) and above 70ºF add points. Correction factor = (0.331 x T/ºF - 23) / 100 or 0.03 pts per 10 ºF Correction factor = (0.595 x T/ºC - 12.5) / 100 or 0.03 pts per 5 ºC This is valid for 0-130ºF or -17.8- 54.4ºC |
|
|
Thread Tools | |
Display Modes | |
|
Similar Threads | ||||
Thread | Forum | |||
Pargo cart specs? | Electric golf carts | |||
torque specs | Gas EZGO | |||
Looking for CC XRT brake rotor specs | Golf Carts and Parts | |||
overbore G9 specs | Gas Yamaha | |||
need engine specs for KF82-FZ340 | Gas Club Car |