Your last generator Maintenance Run

[Patrick Herd]

Don’t know mfg date they were wrapped up but they looked extremely clean & the few we checked were at or above the full charge voltage. We have a pumped storage facility in town called Bear Swamp which my nephew works at & they use them for backup power for pumps & support equipment.
They systematically replace them according to established performance/time criteria so they were professionally tested & maintained and still have plenty of capacity for a small battery backup.
They have 3 plus pallets of them, 30 per pallet.
I would most likely buy a complete pallet & create 2 battery banks.

90cummins

For a full pallet I'd offer maybe 1.5x the going scrap rate, it's a quick profir for him and a cheap battery pack for you.

 

[3930dave]

If you can find out more about their onsite testing program/criteria 90, that may help you budget a bid.

Meaning - are they changed out @ 90% capacity, or 60%, or......

I'd probably want to know that ^ type of info, before budgeting more $ than what Patrick is suggesting.

Possibly they are just going by Time, based on Manufacturer data, and not actually testing each battery.

If you build a monster-pack with that scale of battery, I can see your diesels getting bored with not running !

Rgds, D.

 

[90cummins]

If you can find out more about their onsite testing program/criteria 90, that may help you budget a bid.

Meaning - are they changed out @ 90% capacity, or 60%, or......

I'd probably want to know that ^ type of info, before budgeting more $ than what Patrick is suggesting.

Possibly they are just going by Time, based on Manufacturer data, and not actually testing each battery.

If you build a monster-pack with that scale of battery, I can see your diesels getting bored with not running !

Rgds, D.

I went over & we discussed pricing today & he asked me what they are worth.
I told him you’ve always treated me right give me a price, he threw it back at me & after some thought I offered $20 apiece.
He said that’s exactly what he was thinking.
So for $240 I can replace my 4 L16RE’s.
I priced out 4 L16’s at $435 each @ $1740.
I’ve purchased all my heavy cabling & steel from him, always gave me a great price.
There are 30 on the pallet & I may buy all of them for 2 complete battery banks.
This should give me a day or two before needing to start the generator. That should reduce the fuel consumption way down, perhaps 15-20 hours per gallon.
The engine should be happier running harder & longer.

90cummins

 

[3930dave]

I went over & we discussed pricing today & he asked me what they are worth.
I told him you’ve always treated me right give me a price, he threw it back at me & after some thought I offered $20 apiece.
He said that’s exactly what he was thinking.
So for $240 I can replace my 4 L16RE’s.
I priced out 4 L16’s at $435 each @ $1740.
I’ve purchased all my heavy cabling & steel from him, always gave me a great price.
There are 30 on the pallet & I may buy all of them for 2 complete battery banks.
This should give me a day or two before needing to start the generator. That should reduce the fuel consumption way down, perhaps 15-20 hours per gallon.
The engine should be happier running harder & longer.

90cummins

That sounds like a great deal 90 !

2 Monster Packs in your future...... Voltarra and Battzilla !

Looking forward to your test #'s with the new monsters !

Rgds, D.

 

[90cummins]

Help needed comparing battery capacity.
I’m planning to replace my Trojan L16’s with industrial SBS STT2V420 two volt batteries.
The SBS batteries have the following AH ratings.
8 hr rating of 475 AH’s.
48 hr rating of 596 AH’s.
120 hr rating of 661 AH’s.
240 hr rating of 686 AH’s.

Trojan renamed the L16’s and are now SPRE 06 415 with the following ratings.
10 hr rating of 346 AH’s
20 hr rating of 377 AH ‘s
40 hr rate of 401 AH’s
100 hr rate of 415 AH ‘s
I attempted to use Trojans on line battery sizing guide to compare performance but I’m having trouble making sense of it because they use different hour ratings.
Looking at the numbers it’s apparent the SBS batteries crush the Trojans in performance but how much better are they?
Can someone tell me how L16’s in a 24 volt system would compare to 12 of the above mentioned 2v batteries assuming both were new.
I would like a comparison of them with a 24 hour average load of 300 to 600 watts.

Thanks
90cummins

 

[Patrick Herd]

The discharge curves look pretty similar to me, looks as though you can just compare amp hours to amp hours there. That is 600Ah of Trojan is going to perform more or less the same as 600Ah of SBS.

Peukert's law is pretty universal across all lead chemistries: Peukert's law - Wikipedia

 

[daugen]

Patrick, we learn a lot from you, thank you.
Quite a bit goes over my head, but that's how we learn.

 

[90cummins]

Patrick, we learn a lot from you, thank you.
Quite a bit goes over my head, but that's how we learn.

Still over my head but it’s starting to compute.
90cummins

 

[3930dave]

To paraphrase Duval in a now-old role....... I like the smell of electrons in the morning; it reminds me of Engineering.....

(I work a late-evening shift these days, so it's "morning", and time for first-coffee )

Great explanation Patrick, and thanks for the Peukert reference..... I was familiar with the discharge curves, but not who had defined them...

Interesting section in the wik entry about cascade cell failures..... statistically non-relevant to 90's application, but I was thinking of the long-running EV thread on here, reading that.

Rgds, D.

 

[MAX-24-Dean]

The charge characteristics of tubular positive plates with the lead selenium - antimony alloy in the SST2V420 battery leads to a battery that needs to be fully charge to 100% SOC (state of charge) and placed in float and mantained in float after each discharge cycle or battery life will be shortened.
The Trojan only needs to be brought minimum 70% SOC threshhold to not shorten the battery life. So is much better suited to partial state of charge in my opinion.

SST2V has a 30% of the Ah capacity as a max. charge rate.
The trojan has a 13% of the Ah capacity as a max charge rate.

I am not as well versed on the subject as @Patrick Herd, but I did have experience maintaining Industrial traction batteries during my carreer.
See attached doc's with added notes.

Dean

Edit: With the attached documents you can compare the 20 hour discharge rate given for both batteries. Hope this helps.