UPS Failure's

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GoldDigger

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I think you are reaching for some reason.

The function of a UPS is to provided an uninterrupted power supply to the load.

If the UPS cannot handle powering on and off on the supply side it is worthless.

Actually, I have worked with both wall warts and cheap UPS units that would in fact self-destruct or at least trip internal OCPD if you simply rapidly toggled a snap switch on the input enough times. That never resulted in an out-of-phase condition, just on and off.
And, yes, such equipment might well be considered worthless under those conditions.
My point was that a UPS could be adequately designed for power on and off, both under and without load, but not necessarily what would be seen with an out-of-phase transfer of the input. A UPS connected only to POCO would not be likely to see such conditions. Possible, yes.
Of course all of this is still just speculation, since we do not have information on what failed inside the UPS or even for sure how the ATS, UPS and generator were wired together.
 

templdl

Senior Member
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Wisconsin
Actually, I have worked with both wall warts and cheap UPS units that would in fact self-destruct or at least trip internal OCPD if you simply rapidly toggled a snap switch on the input enough times. That never resulted in an out-of-phase condition, just on and off.
And, yes, such equipment might well be considered worthless under those conditions.
My point was that a UPS could be adequately designed for power on and off, both under and without load, but not necessarily what would be seen with an out-of-phase transfer of the input. A UPS connected only to POCO would not be likely to see such conditions. Possible, yes.
Of course all of this is still just speculation, since we do not have information on what failed inside the UPS or even for sure how the ATS, UPS and generator were wired together.
OK, now that we covered all of this stuff what is your prognosis?
 

GoldDigger

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OK, now that we covered all of this stuff what is your prognosis?
That no further diagnostic steps are likely to be of any use until the OP is able to provide more information. The fact that he referred to phase monitoring in the UPS rather than the ATS makes me question all of the information given so far, including our speculation about how all of the components are interconnected.
And probably the most important information would be what part of the UPS was damaged.

Hard to give a prognosis without a diagnosis. Hard to diagnose without a patient history, an exam, and tests. :)

My prognosis is just fine, since I do not have the problem. :angel:
 
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iwire

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Massachusetts
Actually, I have worked with both wall warts and cheap UPS units that would in fact self-destruct or at least trip internal OCPD if you simply rapidly toggled a snap switch on the input enough times. That never resulted in an out-of-phase condition, just on and off.
And, yes, such equipment might well be considered worthless under those conditions.
My point was that a UPS could be adequately designed for power on and off, both under and without load, but not necessarily what would be seen with an out-of-phase transfer of the input. A UPS connected only to POCO would not be likely to see such conditions. Possible, yes.
Of course all of this is still just speculation, since we do not have information on what failed inside the UPS or even for sure how the ATS, UPS and generator were wired together.

Yeah, and you are not reaching .... :roll:
 
Loads being served by UPS remain powered up until batteries are exhausted. The input is seemingly going away - we are sending to get factory diagnosis. There are no issues with any other loads that generator is picking up, whether resistive, inductive or etc. Again, I go back to my questions concerning the bonding of neutral and potential ground loops.

Thanks.
 

templdl

Senior Member
Location
Wisconsin
That no further diagnostic steps are likely to be of any use until the OP is able to provide more information. The fact that he referred to phase monitoring in the UPS rather than the ATS makes me question all of the information given so far, including our speculation about how all of the components are interconnected.
And probably the most important information would be what part of the UPS was damaged.

Hard to give a prognosis without a diagnosis. Hard to diagnose without a patient history, an exam, and tests. :)

My prognosis is just fine, since I do not have the problem. :angel:
It is very frustrating when we are shooting at shadows.
 

GoldDigger

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Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Loads being served by UPS remain powered up until batteries are exhausted. The input is seemingly going away - we are sending to get factory diagnosis. There are no issues with any other loads that generator is picking up, whether resistive, inductive or etc. Again, I go back to my questions concerning the bonding of neutral and potential ground loops.

Thanks.
Ground loops do not (generally) destroy equipment. And bonding or not bonding the neutral will often not affect operation unless there are GF protection devices involved.

"... remain powered up until batteries are exhausted. The input is seemingly going away"
Now we have a partial symptom to work from!
This is a pretty good indication to me that the battery charging circuitry which should have been fed from the generator while the UPS was delivering power to the loads is not working. If the batteries charge OK when normal AC power is supplied, then there seems to be a wiring problem, ATS failure or a blown fuse somewhere. Not something wrong with the UPS.
If the UPS has a pass-through transfer switch of its own, it should just deliver generator power directly to the loads once the generator starts and gets up to speed. That it does not do this indicates to me that the generator output is not within the voltage and frequency limits set inside the UPS. Again, maybe not a UPS problem. Loads which are not as sensitive to voltage and frequency could operate just fine off the generator.

Check out the generator output in detail, as measured AFTER the ATS.

If the UPS never charges and does not deliver power to the loads when on normal AC through the ATS, then you would be looking at an UPS problem.
 
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