Why buy a sled?

So I have a couple of 1kVA rack mounted APC UPS'es (APC Smart-UPS 1000VA).  We got them for our MDF, while in the midst of a build-out, before the "big UPSes" were moved/installed in the new space.  They worked really well and were already in the racks, so we never bothered to run the main UPSes to these racks... they stayed on generator-backed emergency power, nicely doing their job through multiple power outages.

Recently, I was greeted by the beep-beep-beep'ing of a "your batteries are dead" alert from one of the units.  Okay, it's been four years... I can't really expect more than that from a UPS... let's order some new batteries...

Googling the part # of the UPS, I get two kinds of results.  One for an RBC23 runs between $150-$300 (APC compatible vs OEM, etc) and looks like this:

Okay... looks like a "four pack" sitting in a sled/tray... fair enough.  The other results look like this:


and run about $75 for 4 of them (APC compatible) with no included sled/tray.  Seems kind of a pricey piece of sheet metal and a couple of pieces of wire... Why not just re-use the sheet metal that I already have?

Factor in the cost of band-aids

Pulling the existing tray out of the unit is effortless (okay, it's heavy... but it's nice that you don't need to remove the UPS from the rack).  That was where the effortless part ended.  The sled seemed to be designed by some kind of sadist with a razor blade fetish.  I needed to handle the sled quite a bit to force the batteries (which were held firmly in place with double-stick tape) out.  Heavy object with sharp edges.  What could possibly go wrong?

Hope the Batteries haven't started to leak

The first UPS's batteries were still in decent shape (the UPS wasn't in an alarm state yet), and this was reflected in the physical condition of the batteries.  Maybe a little dust, but otherwise the only problems that I encountered were from handling the sled.  The second UPS had been under considerably more load, and was the one beeping that it needed new batteries.  The inside of the sled was pretty impressive.  Let's just say I'm glad that I had some alcohol handy to clean things up inside.  Could have been a lot worse, but also could have been a lot better.  Quick test.  Try to guess which battery was taken from which UPS:

Of course the fact that the batteries had deformed meant that it was even tougher to get them out of the sled.  Let's just say that some brute force (10lb dumbell and large screwdriver) and ultimately some more band-aids got the job done.  Some more clean-up on the connectors and everything is humming along nicely again.

Was it Worth It?

I hate paying more (or almost as much) for consumables as for the product itself.  Maybe it's a personality flaw of mine, but there you go...  I think that if these UPS'es are still in service in 3-4 years I'll pony up for new sleds... if for no other reason than I don't know how many connect/disconnect cycles the sled's wire harness battery connectors really have in them.  I guess I need to add "leather gloves" to my list of things to keep in the MDF.