Two Smart UPS units - want only one on at any given time

[Anonymous user]

In electrical generator panels, there are "lockout switches" or "manual transfer switches," and I am hoping to see if something similar can be set up with APC Smart UPS units.

If there are two units, is there a way to force one to shut down before the second one comes on?  Can an APC unit be forced to shut down even if there is a load on it?

Can this be done with two SMC units, or is it necessary to have the SMT units with the Smart-Slot?  Maybe one SMC and one SMT unit?  Can it be done through the APC software controlled by a computer?

Thank you for your help. 

(I did try to search, but didn't find anything.  That doesn't mean there hasn't been a discussion, just that I couldn't find it.  If this has been discussed please give the link to that discussion.)

[BillP]

Hi,

Are you looking to have one UPS tell another to start up when it is shutting down or would a command be given by an outside source? Also, when the first UPS is going to be powered down is the AC input state of the second going to change from no incoming AC to incoming AC?  

[Anonymous user]

I had thought that both UPS units would be plugged into the duplex outlet, so they both would have AC, unless the power goes out.

I had thought that somebody would push the ON button for the UPS that was off.  However, instead of immediately coming on, it would wait until the other unit had shut down.  Or if you could push one button, as a signal, as Bill said a command by an outside source, and then the one that is on would turn off, and the one that is off would turn on.

But both could not possibly be on simultaneously, it must be impossible to do, as with the generator lockout switch.  If necessary, I will devote a laptop computer to the task.

[BillP]

Hi Kevin - 

Just so I better understand the application - What exactly are you tying to accomplish? Will they be supporting two different loads or are you somehow trying to extend the overall runtime? 

[Anonymous user]

No, each UPS unit will support its own, separate load.  

However, both cannot be on simultaneously, not even for a minute.  And, when the one is going to switch on, the other must be forced to turn off even if there is power being drawn from it.  This is not for a server or any computer where a nice shutdown needs to occur and takes five minutes of backup power.

[BillP]

Hi,

You would need Smart-UPS with AP9631 and AP9810s attached. You would need to configure the contacts to communicate between the 2 UPS so if one is on the other is off. If one is powering on it would shut the other down. I would also recommend adding outlet on delays to be sure only one UPS was providing output at a time. 

Example, UPS 1 is on and UPS 2 is off. UPS one is going to power down so the state changes on its contacts which in turn changes the state of the contact on UPS 2 which causes UPS 2 to power on. UPS 2 has been configured with 30 second outlet on delay to allow UPS 1 to power off its outlets prior to AC being provided by UPS 2. 

[Anonymous user]

On 1/29/2019 3:57 PM, Bill said:

Example, UPS 1 is on and UPS 2 is off. UPS one is going to power down so the state changes on its contacts which in turn changes the state of the contact on UPS 2 which causes UPS 2 to power on. UPS 2 has been configured with 30 second outlet on delay to allow UPS 1 to power off its outlets prior to AC being provided by UPS 2. 

OK, yes that is exactly what I am hoping for.  

Is it possible for only one UPS to have the AP9631 card, have an AP980 connected to it, and the other be a "SMC" version and only connect the AP9810 to it?  Or does it have to be both with AP9631 cards also and thus both "SMT" versions?

And thank you so much Bill for the information.  

[BillP]

Hi,

Both UPS need to have the AP9631 and AP9810 aas the AP9810 must be connected to the AP9631. The SMC model Smart-UPS are not compatible with AP9631.

I hope to have some free time middle of next week and will run a test and report back the pin set up.

[Anonymous user · Accepted solution]

Bill, thanks for the information.

I was greatly hoping that at least one of them could have been an SMC model.

I have an older Smart-UPS 750xl, from looking at the compatibility chart that one will work if it is APP v.5.0.3.  So that sounds pretty technical and brings up another question.  Do both AP9631 cards have to be the same exact version, or will any version past APP v.5.0.3.?

And, again, without your help Bill, this would be completely impossible for me!