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UPS model is Legrand Keor SP 1500VA
Tested the 2 batteries on their own with 12v supply under load. Slightly small load about 300mA but steamed for about 10 minutes per battery. Measured and work great. Both 13.5v. Together 27v.
Connected the device to the software. Batteries show 95%. All good.
Unfortunately the front panel LED indicators don’t work (different problem or an indication of the source of problem?). No led screen or other indicators available.Actually because of the front panel failure I bought new batteries (12v-45w - 9Ah) 2 months ago, but they didn’t fix the problem and now I realised that the problem went even further and the ups doesn’t work on battery mode.
For testing purposes. I used just an ipad while charging. The load is small. Around 100mA. The UPS is 1500 VA - 900w (700w in battery mode), so it’s way under loaded when it charges.
The UPS passes power to the device perfectly well, but when I disconnect it from mains (for testing) and it enters “ battery mode” I hear a relay clicking sound, it works fine for some seconds but then another relay clicks and the power stops and the device stops charging anymore. So the battery mode doesn’t work.
I repeat the batteries on their own work fine with way higher load. 300mA per battery comparing to the 100mA i test both combined in the ups circuit.
I’m certain the problem is on the controller board. And I suspect the Mosfets inverter section.
There are 5 relays (2 for switching modes and 3 for the appropriate voltages on the transformer), 8 Mosfets , some electros on the upper side and few smd Ics, along with smaller smd components on the underside (some people say that an smd comparator -324- is a common cause of trouble on simple line interactive ups units).
Does anyone know of specific common Ups pcb controller issues? Mosfets, relays, or particular ICs? Anything similar to the symptoms I describe?
Tested the 2 batteries on their own with 12v supply under load. Slightly small load about 300mA but steamed for about 10 minutes per battery. Measured and work great. Both 13.5v. Together 27v.
Connected the device to the software. Batteries show 95%. All good.
Unfortunately the front panel LED indicators don’t work (different problem or an indication of the source of problem?). No led screen or other indicators available.Actually because of the front panel failure I bought new batteries (12v-45w - 9Ah) 2 months ago, but they didn’t fix the problem and now I realised that the problem went even further and the ups doesn’t work on battery mode.
For testing purposes. I used just an ipad while charging. The load is small. Around 100mA. The UPS is 1500 VA - 900w (700w in battery mode), so it’s way under loaded when it charges.
The UPS passes power to the device perfectly well, but when I disconnect it from mains (for testing) and it enters “ battery mode” I hear a relay clicking sound, it works fine for some seconds but then another relay clicks and the power stops and the device stops charging anymore. So the battery mode doesn’t work.
I repeat the batteries on their own work fine with way higher load. 300mA per battery comparing to the 100mA i test both combined in the ups circuit.
I’m certain the problem is on the controller board. And I suspect the Mosfets inverter section.
There are 5 relays (2 for switching modes and 3 for the appropriate voltages on the transformer), 8 Mosfets , some electros on the upper side and few smd Ics, along with smaller smd components on the underside (some people say that an smd comparator -324- is a common cause of trouble on simple line interactive ups units).
Does anyone know of specific common Ups pcb controller issues? Mosfets, relays, or particular ICs? Anything similar to the symptoms I describe?
