Good morning all,

I am looking for so guidance please in relation UPS battery handle failures and wondered if anyone else has experience of a similar incident?

Recently one of our engineers was completing a battery replacement for a client and whilst lifting the batteries in to the UPS one of the handles failed resulting in the battery dropping to the floor and the handle striking the engineer on the chin.  Thankfully the injury was only minor.

The batteries in question were YUASA SWL3300 37.5 kgs.  

The room where the batteries were being stored was cold, warehouse conditions.  I wondering if this could manual handling issue i.e. if the engineer was to unconsciously favour one hand over the other causing more weight to be applied to one site of the battery handle, or if it could be a design issue?

Its worthy of note that the engineer is very experienced and has completed numerous battery replacements over the years with no previous issues.

Many thanks

Karoline

Why is one engineer lifting a 37.5Kg battery on their own?

Thanks for your reply.

The handles are made of plastic and attached to the top of the battery at either side.  It was the left handle which failed in the middle.  

After chatting with the manufacturer they have advised that they are not aware of any similar failures occuring, which drew me to the manual handling aspect.  Looks like I need to go back to the supplier.

Below is a link to the Techical Data Sheet for the battery in question.

https://www.yuasa.co.uk/swl3300-swl3300.html

The clue might be in the storage temperature of the battery and the plastic handle. Check the battery data sheet for the recommended storage temperature. You might have had a brittle failure of the handle if it has been stored at too low a temperature and then lifted. The material might have lost its ductility and hence the stresses imposed by lifing causing failure.

Originally Posted by: paul.skyrme

I'll go with Ian Bell2, probably brittle fracture of the polymer material in the handle due to reduced ductility as a function of temperature.

Whilst when static the battery may operate down to extremely low temperatures, I suspect that like many polymer materials they should not be manipulated when the ambient temperture is tending to 0 Celcius.

I doubt that.  The battery is rated for all use down to -15C and storage and discharge to -20C.  It seems to me very unlikely that the manufacturer would use a plastic that becomes dangerously brittle within the stated operating range of the battery - and at 'warehouse conditions' I'd exepct this battery was in the 10 to 15C range. 

Yuasa is a reputable manufacturer (though I've only dealt with smaller batteries from them) and if they had a range of batteries that were brittle below 0C I'm sure they'd do something about it. 

There are polymers with glass transition temperatures down at -100C and lower - there's nothing fundamental that makes a polymer brittle below 0C (and 0C is a special temperature only for water - why would a polymer care that it's at 273K rather than 274K?)

It's much more likely a one-off manufacturing fault or in-service damage, I think.  The handles on big batteries always seem quite flimsy to me (domestic car batteries likewise) - I tend to use the handles only to lift the edge to get my hands under the bottom, though that's not necesarily feasible slotting one into a UPS.

i'd start by looking at why are they being stored at that height anyway, if they are UPS units for a Server rack then they should be no more than 10U's high.

I wouldnt expect cold to affect the plastic and cause them to fail

I would ensure a min of 2 people move the UPS and that they are provided a toolbox talk on how to check it before they move it.

Originally Posted by: craigroberts76

i'd start by looking at why are they being stored at that height anyway, if they are UPS units for a Server rack then they should be no more than 10U's high. 

Has something been deleted from this thread? I cannot see any mention of height.