Genie GS2646 battery/charging issues.

[bmstew313]

I'm having issues determining if my batteries are bad in my Genie scissor lift, model GS2646 with Trojan T105 batteries. The batteries are mixed batteries from 2022. Fully charged, the batteries read around 26 volts as a full pack, individually about 6.5 volts a piece. When a function is used, the voltage drops to around 22-23 volts, but returns when use of the function stops. The meter on the platform control drops pretty quickly as in about 100 yards, goes from 6 bars to 2-3 bars and can sometimes not even get a full days use out of the lift. Our manlift rental department replaced the charger thinking it was bad, so I can rule the charger out already. I had a brand new ECU to rule that out, thinking it was sending a bad signal to the platform controller, and it made no difference. The motor gets warm, but never hot. I see you have mentioned using a carbon pile tester to load test the batteries, but from what I have read, most carbon pile testers will not test deep cycle batteries. So my questions are 1) do you have a carbon pile tester that you recommend? and 2) would you have any other recommendations on where to go from here? My supervisor doesn't seem to think that the batteries are bad, but everything is leaning towards bad batteries. I saw that it was mentioned somewhere that a fully charged battery pack would be around 28 volts or better, and if that is true my, batteries are already partially discharged and with the voltage drop that I am experiencing seems as though they could be the issue.

 

[Jayceesdad6]

What do you mean by "mixed" batteries? Are they all Trojans and 225 AH?

I'll walk you through the process I've used daily for years, after teaching myself and arguing with my old supervisor over it. Similar situation to you. Of course, all of this is assuming that your electrical parts are all clean and corrosion/cut/pinch free throughout the machine.

First question is what type of charger was installed? Depending on the charger, it may come installed with the incorrect charging algorithm set. Newer ones are super simple to change to the correct algorithm. There are certain algorithms set for different AH, brands, and types of batteries. It's often overlooked, but is important. If you let me know what charger you have now, I can help with that. By the way...90% of the time, the issue is not a bad charger. Manuals for charger manufacturers even state this and say to please ensure that the charger is definitely bad before purchasing a new one. I've seen tons of people replace a charger, convinced that is the issue...only to realize the issue was the batteries shortly after.

If the algorithm is determined correct, and the charger is for sure okay, let it charge overnight. Make sure all your battery cables are tight. After the charge, run it around for a little and go up and down a little bit. Now take your hydrometer/refractometer and get a Specific Gravity reading of each cell in each battery. They should all be AT LEAST 1.25. If all are lower with not much discrepancy between each other, your batteries are most likely starting to go bad/get old. Let's say you have 2 cells that are reading good, and 1 cell is super low...you have found your problem. If all cells pass your gravity test, move onto the next step.

If you dont have a load tester, just use your volt meter. Preferably one that has a max/min setting. Load test each battery individually. Set your meter to voltage and activate the "min" setting. Put your gator clips across battery 1, get some weight in the basket and go up and down a bunch of times. Lifting gives more of a load than driving does. Record the "min" or how low the voltage dropped and do this for all batteries.

You are more than likely correct on it being the batteries, especially if the charger is set correctly. However, following these steps should help you convince your supervisor and show him that you've properly diagnosed the issue.

As for what actual load tester I use: Westward 3Z634R. 200A.

Feel free to reply or messageme if you need more help or have any other questions!

 

[Sargehw]

Might also want to, heck the battery acid in the battery’s u might have a bad cell and don’t know it, testers are cheap to check the acid, I’ve seen that many time with battery’s u think are good and load tested ok but bad cell .