We believe that the A4 card is fault and I am preparing one to send to you and will forward a quotation today.
In the meantime we need to establish what the fault with the transformer is. Please could you carry out these tests?
• Switch on UPS, output idle
• Measure DC-current at terminal 1,2 and 3 of T2 using a DC-Current Clamp
• Note values and send them to me (Should be about 0A)
• Switch off inverter (DC-supply must be on)
• Measure DC-voltage On Transducer A29/X15:2 to ground
• Measure DC-voltage On Transducer A29/X15:5 to ground
• Note values and send them to me (Should be about 0V)
A more complex test would be:
•
Isolating the output transformer T2 from primary and secondary side (remove all cabling from terminals 1 to 7)
• Connect terminals 4 (N), 5 (L1) , 6 (L2) and 7 (L3) to 380/220V mains supply
• Is it still noisy ?
IMPORTANT:
MAKE SURE THAT THE PRIMARY SIDE OF T2 (TERMINALS 1,2,3) IS COMPLETELY DISCONNECTED