Below is an email I recieved from a Electrician who is having a problem on a college campus where he works any ideas or suggestions will surely help. thanks:
Craig,
The new cables was installed by your company and tested on , or around 10/31/2010 By ------ testing Co. They left after testing that evening. We brought power back up and It was on for and 10 min. with no problem, we were in the process of bringing the buildings back on line, when the circuit blew while bringing up one of the building. It took out the C phase pole-top fuse, (200 amp ), and one lighting arrestor in our central plant gear. We replaced the lighting arrestor and refused the pole top. This time the circuit held.
The next outage was to have Absolute remove parts from our Ball/Anderson pad mount switch for repairs, check the capacitor bank, and 4-1 air switch. The air switch was at this point not operable and we decided to re-energize by the pole top switches. We brought up C phase first, B phase second, and when we brought in A phase the B, and C fuses blew taking out the lighting arrestors. We replaced all three arrestors,(10kv), and refused,(200 amp), we brought up A phase, B phase, and C phase in that order. The circuit held.
Last month we brought the circuit down to re-install the parts to the ball/Anderson pad mount switch parts, that were removed on the previous outage. Again while re-energizing the circuit, this time A phase first, B phase blew when energized, also taking out the B phase lighting arrestor. We replace the arrestor, and fuse. Re-energizing went without any problem?
We only have three transformers that become energized without load during this time. I believe all are oil cooled Delta-wye.
We will have an outage on August 20th. To replace the 4-1 air switch, and would like to have this problem resolved by then. Do you have any suggestions as to what might be causing this?
Thanks
John
Craig,
The new cables was installed by your company and tested on , or around 10/31/2010 By ------ testing Co. They left after testing that evening. We brought power back up and It was on for and 10 min. with no problem, we were in the process of bringing the buildings back on line, when the circuit blew while bringing up one of the building. It took out the C phase pole-top fuse, (200 amp ), and one lighting arrestor in our central plant gear. We replaced the lighting arrestor and refused the pole top. This time the circuit held.
The next outage was to have Absolute remove parts from our Ball/Anderson pad mount switch for repairs, check the capacitor bank, and 4-1 air switch. The air switch was at this point not operable and we decided to re-energize by the pole top switches. We brought up C phase first, B phase second, and when we brought in A phase the B, and C fuses blew taking out the lighting arrestors. We replaced all three arrestors,(10kv), and refused,(200 amp), we brought up A phase, B phase, and C phase in that order. The circuit held.
Last month we brought the circuit down to re-install the parts to the ball/Anderson pad mount switch parts, that were removed on the previous outage. Again while re-energizing the circuit, this time A phase first, B phase blew when energized, also taking out the B phase lighting arrestor. We replace the arrestor, and fuse. Re-energizing went without any problem?
We only have three transformers that become energized without load during this time. I believe all are oil cooled Delta-wye.
We will have an outage on August 20th. To replace the 4-1 air switch, and would like to have this problem resolved by then. Do you have any suggestions as to what might be causing this?
Thanks
John