SMT1500I Battery warning

[richardpearce_apc]

This was originally posted on APC forums on 5/23/2015

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I have a SMT1500I which has just had its battery replaced. The unit is continually giving the warning 'no battery connected'. Is there any diagnostics I can perform or hard resets available?

Unit info is as follows

Smart UPS: SMT1500I
AS1148112065
UPS Firmware 1: UPS 05.0
UPS Firmware 2: COM 02.1
UPS Firmware 3: UBL 05.0
UPS Firmware 4: CBL 5.21

[Terry_Kennedy_apc]

This was originally posted on APC forums on 5/23/2015

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Was this an APC-branded RBC battery or one of the 3rd-party "reuse your existing cables and connectors" ones? If the latter, since there is more than one actual battery, is it possible you connected the wiring improperly? The APC one would have a single connector which only plugs in one way.

[richardpearce_apc]

This was originally posted on APC forums on 5/24/2015

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No was an original branded APC battery. Slightly worried I may be just throwing good money at it by buying another... I'm going to try and upgrade the firmware as the next port of call..

[Terry_Kennedy_apc]

This was originally posted on APC forums on 5/24/2015

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Did it also give the "No battery connected" error before you replaced the battery, or a different message?

Since you have an APC battery, it should have an APC serial number sticker with the RBCxx part number and a serial number of the form "xxyynnnnnnnn" where yy represents the year of manufacture. Can you confirm it is 15? Or possibly 14, if it has been sitting in a warehouse somewhere.

Do you have a multimeter or DC voltmeter? Can you disconnect the battery and measure the voltage on the battery connector? I believe this pack has 2 12V batteries, so you should see about 24 Volts DC at the connector.

Your UPS is from 2011 according to its serial number, so it almost definitely needed a new battery pack. My "rule of thumb" as an end user of the Smart-UPS is that the first battery replacement usually works well, but by the time that battery needs to be replaced, it is time to look for a new UPS as the second replacement won't last as long as expected. This is because I've found that the charging voltage of the UPS drifts out of spec (almost always to the high side) over time and overcharges the batteries.

If you need to replace the UPS, consider the APC Trade-UPS program where they give you a discount on a new unit in exchange for your old one. But compare the cost of that with the best discount you can get on a new one without trade-in to make sure you are getting the best deal.

[richardpearce_apc]

This was originally posted on APC forums on 5/24/2015

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Terry,

Thank you for your response. The battery part number indicates 13.... It is giving a steady 24v.

Yes the unit was giving the "No battery connected" before replacement.

Guessing it's time for a new unit....

[Terry_Kennedy_apc]

This was originally posted on APC forums on 5/24/2015

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If the RBC serial number has 13 in the year field, it is at least 17 months old. I'd suggest that you shop elsewhere for your replacment UPS - aside from the problem with getting one with old batteries, I think the warranty starts at time of manufacture unless you have a receipt from an authorized reseller, in which case the warranty starts then as long as you provide that to APC when making a warranty claim.

If the place where you purchased the battery is (or says it is) an authorized APC reseller, you may want to PM Angela (since you may not want to name them here in the forum) so that she can have APC contact them and discuss inventory practices and stock rotation.

[BillP]

This reply was originally posted by Angela on APC forums on 5/26/2015

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I would also make sure you've let the new battery charge up for at least a day. A weak, discharged battery can display this behavior and not be "seen" by the UPS.

[richardpearce_apc · Accepted solution]

This was originally posted on APC forums on 5/26/2015

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So, I bought a second battery. Serial shows as 14 and ... works first time! Thank you for the help!