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FLA Float Voltage - Wall Charger

Delmar

Solar Addict
Joined
Dec 9, 2019
Messages
817
Location
Lake Conroe Texas
Getting ready because ERCOT keeps threatening rolling blackouts for this summer. My inverter powers from my used 48V golf cart that came with good Trojan FLA batteries and Delta-Q 18A charger.

My 400W solar panels with MakeSkyBlue MPPT easily charge for my driving needs. However between rolling blackouts the Delta-Q charges at 1000W and at night. Whenever there is a threat of severe weather the cart is ready and on the wall charger.

The Delta-Q only floats at 51V where the Trojan specs recommend 54V. I’m not getting most of the available capacity. Actually surprised how well the batteries have performed at the low float voltage.

Does anyone have experience with the Delta-Q? I understand they can be user configured. Otherwise can you recommend a good replacement 48V 1000W~ish wall charger that will float at 54V, and can be reconfigured for my future upgrade to LiPo?
 
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There is really no need to float the golf cart if you are using it .
float just Maintains the battery at full charge.
i charge a 48 volt bank of 16 GC battery’s and do a 3 hour absorb charge and I’m done no float , I can come back in 2/3 weeks . And my battery’s are still sitting at 51.5 or more full charge is 51.2
My solar panels charge at 4500 watts and do a 3 hour absorb and float at 54volts But that just powers loads .
 
between rolling blackouts the Delta-Q charges at 1000W and at night. Whenever there is a threat of severe weather the cart is ready and on the wall charger.

The Delta-Q only floats at 51V where the Trojan specs recommend 54V

If the Q were not there solar would not be floating them at all (no sunlight). I would not worry about 51v Vfloat; it's gravy.
 
Follow the Trojan specs!

Of course you are happy with how the batteries are performing at a lower-than-specified float, because they are new! Give them time - which is cut even shorter than normal to start to sulfate. Then you'll be in a rush to go to 54v.

Trojan gives their specs for a reason. Float is wise. Do it right, or why even come to the forum just to wing-it?
 
I still need to purchase a 1000W-ish 48V wall charger that allows float adjustability. The Delta-Q has no readily accessible adjustments.

My plan is to normally float at the Trojan recommended 54V. However when there is a threat of severe weather I may temporarily bump to 56V-57V for a few hours to ensure maximum grid-down runtime. Not overly concerned with battery health during a severe weather event, will sacrifice for keeping the lights on and the fridge running.

Per my original post…can anyone recommend a good 48V 1000W~ish wall charger where I can easily configure the float voltage?
 
Per my original post…can anyone recommend a good 48V 1000W~ish wall charger where I can easily configure the float voltage?
It sounds like you might be able to get away with a power supply then. Something like beefy one was recommended on another thread could work. You would purchase the 48v or the 60v model and use the potentiometer to adjust to the volts you need.

If you contact the seller they should be able to give you the range of adjustment which hopefully is more than the +/- %3 dimming range, if not that product won't work for you.

Edit: So I previously answered your question without carefully reading your post. What is the specific gravity of the cells? If these were my batteries I'd be keeping a close eye on SG and at least a few times per years taking them up to 2.6 volts per cell for at least a few hours.
 
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It sounds like you might be able to get away with a power supply then. Something like beefy one was recommended on another thread could work. You would purchase the 48v or the 60v model and use the potentiometer to adjust to the volts you need.
Interesting recommendation for a conventional (constant voltage) power supply. In theory I could take the 90V output into my MakeSkyBlue MPPT where it would control the voltage & current to the batteries, plus is accessible for voltage selection.
 
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