UTS10BI circuit status when connected to UPS?

[paulsnyder_apc]

This was originally posted on APC forums on 3/25/2013

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I recently connected an APC Smart UPS (SMT1500) to my UTS10BI.  The UPS is plugged into the convenience outlet on the front panel of the UTS10BI and I have the UTS10BI supplied power cord connected to the front panel inlet to the back outlets on the UPS.  I then configured on the UTS10BI the circuit (Circuit #4) that has my computer and two wireless routers (includes Internet modem) on it.  I used the pre-configured default settings for "Computer" on that circuit.  So, to confirm the settings, the circuit is uninterruptable.  Then I flipped off the breaker to that circuit in my main panel to simulate the power going out.  The results are as follows:

1. The UPS picked up and fed power to the computer circuit. Good!

2. The convenience outlet (Circuit #1) on the UTS10BI went into fault mode with no power feeding the UPS.  I did not flip off the main breaker or the circuit breaker in the main panel feeding Circuit #1, just the circuit breaker feeding the computer circuit on the UTS10BI.  I do not understand why it did this. Can you help explain why?  Is there something about the UTS10BI circuit settings for Circuit #1 that I should be aware of?

3. I flipped the breaker in the main panel feeding the computer circuit in the UTS10BI back on.  I then checked the status of the circuit (#4) on the UTS10BI and it shows the power source as the UPS.  I expected it to show Utility.  After I thought about it, maybe it is suppose to read UPS. Am I right?  The UPS is showing in its' display the amount of the load, but it does not indicate it is drawing from its' battery and Circuit #4 is receiving power.

Any input/help would be appreciated.  I am just trying to figure out the nuances of my setup.

[BillP]

This reply was originally posted by Secret on APC forums on 3/25/2013

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Circuit 1 is what feeds power to the Convenience Outlet on the UTS. When cutting power to circuit 4, circuit 1 must now support it's own load as well as circuit 4's load. If circuit 1 senses too much current draw now that it has the extra load, it will enter an overload condition and stop passing power. This may explain why the UPS is now on battery. It may be best to reduce the combined load between Circuit 1 and Circuit 4, to something below the 15amp maximum.

[paulsnyder_apc · Accepted solution]

This was originally posted on APC forums on 3/26/2013

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Thank you for the input.  I tried recreating the circuit fault and can't.  So at this point it becomes a moot issue.

With regards to Circuit #4 showing the power source as "UPS" when set up as "Uninterruptible", apparently this is the way it should be.  The following is from the owner's manual.

UNINTERRUPTIBLE

-there is continuous backup power supplied by a UPS. Utility power flows into the UPS and from

the UPS to the connected load. This provides power and protection for the load during any utility power fluctuation.