Is a Serial Port a Serial Port?

[SamirD_apc]

This was originally posted on APC forums on 1/6/2016

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I have an SC620 that just recently failed and have a few older units like a SmartUPS 1000 (Net model) as well as a 450 that I can swap in place temporarily.  But the SC620 had some proprietary systems connected to the serial port on the SC620.  

My question is will these same systems be able to communicate with the 1000 or 450 in the same manner?  In other words, do the older units 'talk' the same as the newer ones?  Or were there protocol/firmware changes on the newer ones that make them incompatible with the older ones?

Thank you in advance for any insight.

[UnexpectedBill_apc]

This was originally posted on APC forums on 1/7/2016

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Yes. All of the UPS units you have utilize the UPSlink protocol, same as your fallen SC620. They also support simple signaling if your application makes use of that instead.

Be aware that the currently produced SmartUPS (models SMT, SMX, SMC, and SURTD) product line uses a different and unfortunately not publicly documented communication protocol known as Microlink. Some of these newer models offer the ability to communicate using the Modbus protocol, which must be enabled prior to use. Modbus is available only with certain firmware revisions. There's also a legacy communications card available for the newer models having SmartSlot expansion capability. This card provides UPSlink compatible signaling. (I don't know if it supports simple signaling.)

[Rooster_apc]

This was originally posted on APC forums on 1/7/2016

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The spec for the UPSlink protocol has recently been officially released and can be found here: http://www.apc.com/site/support/us/en/faq/?page=content&country=ITB〈=en&locale=en_US&id=FA276164&red...

Hope this helps.

[SamirD_apc]

This was originally posted on APC forums on 1/7/2016

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Thank you for the reply.  One thing I should have specified is the year of the older models.  They are from the 2000s.  The face of both look like this:

Will these simply plug in and talk properly to whatever was connected to the much newer sc620?

[BillP]

This reply was originally posted by Bill on APC forums on 1/7/2016

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Hi,

The UPS image is model SU450 or SU450i and communicates using the same UPSLink protocol as the SC model. If the 1000 is model SU1000NET or SU1000NETi then it would also utilize the UPSLink protocol. 

[SamirD_apc · Accepted solution]

This was originally posted on APC forums on 1/7/2016

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Excellent. Thank you! At least we can be up and running with a UPS while we figure out the issue with the SC.