APC Smart UPS3000

[BillP]

Dear Support,

I have a smart ups 3000 (model SU3000|NET) which is around 10 years old. It has been put in storage without the batteries connected.

We are trying to revive it and put in fresh 48V DC to the battery compartment.

with the battery connected and without mains connected I pressed the on/off button on the front panel. The ups switched on with all lights on the penal illuminated then it went off again. I disconnect the battery and reconnect the battery and there is a relay click sound. 

I attempted the switch on the ups again and the same thing happen.

Q. I would like to know if this is bacause the mains is not connected and the ups will not run on battery alone without the mains connected.

Thank you in advance and hope you can assist me. 

[BillP · Accepted solution]

Hello Lee,

I am sorry that you ran into an issue with your APC unit. As you seem to know, the batteries have a short shelf life when not in use, and only 3-5 years when in use. 

When you replaced the battery, did you use an RBC or did you replace the individual cells?

Also, 10 years is a long time for these units in general. Typically these units last 5-7 years, because of different electrical components, like capacitors, can reach end of life and prevent the unit from working correctly. It might not be the battery, but I cannot say for sure at this point. If you are interested we have a Trade-UPS program where you can purchase a new UPS at a discounted rate, and we dispose of your UPS at no cost to you. 

Thanks,

Shanon

[BillP]

Dear shanon,

Thank you for your reply. Whom do I contact to get into this replacement program in Malaysia? 

[MarkC_apc]

You did try hooking up the mains, with batteries and get the same results?

[BillP]

There is a lot of information on this page: 

http://www.apc.com/my/en/how-to-buy/index.jsp

[BillP]

Dear Mark,

As per your suggestion, I have connected the ups to the mains with the working battery and it stated to hum (the fan spinning) When the power switch is pressed, it started up and done its diagnostic sequence then went online. Thank you very much for the heads up, now i know the ups is "smart" it will go into backup mode only if certain conditions are met (ie when the mains fails and batteries are in good charging condition). 

On more thing is I found that this ups  is not using the standard 17aH battery. It has 4 serially connected 7aH batteries which is what I have replaced as well. Will this be any problem? I believe it has been using the 7aH batteries for some time without any detrimental effect on the UPS charger.

Further advice appreciated. TIA 

[Anonymous user]

The worst that I believe is likely to happen will be a potentially incorrect indication of remaining runtime on the unit or its management software.

Is this a rack mounted or freestanding tower style UPS? If it is rack mounted, it may have to use the smaller batteries.

[BillP]

It is a tower unit and should have came with the 17aH batteries as standard. However the face plat on the ups battery compartment stated it can take 10aH or 17aH batteries. I only worry if the smaller rating batteries (7aH) will be overcharged.  

[MarkC_apc]

I've not encountered such battery configurations as you describe and struggle to understand how this was done.  The RBC11/55 battery systems have 2 sets of 2 ~ 18 amp hour batteries (in series).  Each set is "glued" together and have "24" volt grey Anderson connectors (APC proprietary).  The SU/SUA "towers" depend upon each grey connector being connected inside the battery compartment with the two Andersons wired in series for the "48" volts required.  Did someone take the much smaller 7 amp hour batteries and wire them up in a similar scheme?  That would result in the batteries being dangerously floating around inside the compartment??  If you can send a picture, that might help.

Mark

[BillP]

Dear Mark,

Yes your description of the RBC system is entirely correct. The previous support guy of this UPS must have hack out the scheme of replacing the batteries with the probably 'rackmount type" batteries and wired them for 48v accordingly using the original anderson connectors.  Actually the batteries sits nicely in the battery bay of the Smart3000 and can only move back and forth slightly. will provide a pic when i get to take one.

Hopefully the charger will not have any problem with overcharging the smaller 7aH batteries.

[Anonymous user]

On 9/19/2016 7:44 PM, lee said:

Hopefully the charger will not have any problem with overcharging the smaller 7aH batteries.

I don't believe we can hope for an official answer, other than this sort of thing not being recommended. (Which of course it isn't, as this UPS will be quite rude to small batteries if it is under heavy load and the inverter is running.) Discharge those batteries fast enough, or near enough to what looks like a short circuit from their perspective, and I suspect there is the possibility of case cracking or explosion if the battery cannot ventilate any gases it might emit quickly enough.

(A secondary explosion might take place if something touches off the hydrogen gas that might be emitted. That something could be as tiny as the spark produced when a relay makes or breaks, or even from the hookswitch contacts in a telephone.)

They're all lead acid batteries, so the charge and discharge curves ought to be very much the same -- it'll just happen faster for the smaller batteries. The charging circuit's regulation ought to work just fine. Near as I can tell from various experiments, it doesn't care in the slightest if the batteries charge up faster than "expected" and it will not damage them.

[MarkC_apc]

If the "hack" actually fit 8 (2 sets in parallel) of the small batteries - that would be the same as the rack mount of the SU3000RM.  I'd guess that was not possible - likely 4 which is less than half the watt-hrs required for this unit.  Accordingly, put less than 1/2 wattage load or limit it to around 1000 watts or so - to be safe with the battery wiring/fuses.

[BillP]

Dear all,

Thank for all the advice rendered. Will replaced the batteries with the RBC type ASAP. cheers.