Anand Gupta
Electrical
- Aug 11, 2021
- 2
One of our Power Transformer 132kv/11kv generating humming sound and also had vibration, transformer body and nearby steel structure are vibrating too much.
1. its WTI and OTI temp increasing 2 degree/Hrs without load, we isolated the T/R power after 60' temp.
this prob occurred after short circuit the outgoing Bus one ph. with "RAT" inside the VCB breaker.
T/R HV (STAR connection) Resistance is 1.155 ohm to 0.859 ohm between different taps
T/R LV (Delts connection) Resistance is 17.28, 19.48, 17.5 of R-Y, Y-B, B-R ph in mili Ohms
Voltage and Current are balance in Secondary winding.
TR megger are ok,
please help what to do
1. its WTI and OTI temp increasing 2 degree/Hrs without load, we isolated the T/R power after 60' temp.
this prob occurred after short circuit the outgoing Bus one ph. with "RAT" inside the VCB breaker.
T/R HV (STAR connection) Resistance is 1.155 ohm to 0.859 ohm between different taps
T/R LV (Delts connection) Resistance is 17.28, 19.48, 17.5 of R-Y, Y-B, B-R ph in mili Ohms
Voltage and Current are balance in Secondary winding.
TR megger are ok,
please help what to do