...we are NOT talking about those machines; I know the difference, man... gimme a fucking break. You're making a straw-man argument here. Completely different class from the ones I serviced regularly, and I specifically stated that. As soon as I said 1.5-5KVA, I KNOW you knew the difference.
Those systems I worked/work on are mostly used used in retail, so aren't going to be the top tier, "failure is not an option" class machines... but even they are not the same class as this decades-old consumer grade unit from CompUSA.
What those classes of deployment use is irrelevant here. That is not appropriate technology for this application. That UPS probably came with a PowerSonic or equivalent Chinesium battery, and spending 40-50 bux on a genuine Yuasa "upgrade" is money wasted in this application.
As for the float charge... I think you need to review that. I know from personal experience that a new known good motorcycle or garden tractor battery used in this application will start to boil in a few days or a week; I've tried it on two different occasions. Shallow-cycle starting batteries do not tolerate constant float-charge the same way that deep-cycle batteries do.
I think you'll find the difference is in fact the IR of the battery... but I don't want to start another shit-flinging match here.
mnem
Standard SLAs are not deep cycle. That would be the kind that they use in mobility scooters etc, "traction batteries" I believe they are known as.
I maintain (crap pun, unintended, keeping it anyway) that if your charger is boiling liquid lead acid batteries, it's just set too high. You shouldn't see that kind of reaction unless you're doing an equalisation charge.
My principal point is this: you can spend idk £5-10 on a cheap shit 12V 12Ah battery, that will probably last 6 months, and will probably be actually around half the claimed capacity, or you can spend £30 or so on a decent branded one that has all the chooch it says it does, and it'll last 5+ years. If you tweak the float voltage down to 13.2-13.5 or so, a lot +.
Modern UPSes are a bit more complex and do maintenance on the batteries; the SmartUPS 1500 I have will do load testing for a few seconds every day, and can also be programmed to periodically do a maintenance cycle where it runs off the battery to a specific discharge level.
I doubt the one Vince has is that sophisticated. Point is, no it is not "set too high".
It is set appropriately to the battery tech it is designed to use. And even a low trickle charge is not recommended for a starting battery. There's a reason we have smart "automatic maintenance chargers" for your motorcycle and car batteries in storage: They
do not apply a float charge;
they monitor voltage and charge cyclically.My main point is being completely overlooked here; which was that trying to use a starting battery with this UPS is simply the wrong kind of battery for this application. As for your broad, sweeping ridiculously broad generalizations about the quality of Chinesium batteries... Come on man. I know the difference. But the prejudices you are repeating here about them are simply outdated rubbish.
The Chinese manufacturers own battery technology now. Even their cheapest shite is still more than good enough for this application.6 months lifetime is just a BS number you literally pulled out of your arse, and I know you know it's BS. The entire world runs on cheap Chinese batteries now, and I
never advocated getting the cheapest no-name shite ones; I specified the brands I recommend as I know they are not shite.
Speaking of which, another brand to look for is CSB: They are a Taiwanese manufacturer like Yuasa; by now, possibly even all the same company.
But they often do come up at prices within a couple dollars of the PowerSonic and ExpertPower when they're getting close to their "best by" date, and those I'll stack up next to brand-new Yuasa any damn day of the week, application for application.
Cheers,
mnem
*juicy*