Sibeen, the UPS at this building failed a couple months back. The SCRs for static switch failed while the UPS saw an overload condition. The UPS could not transfer power to bypass and shutdown. The SCRs were replaced but the cause of the failure was never determined.
Ghostbuster7: If by on-line you mean that the output power is normally in-line with the rectifier and inverter, then yes the unit is a full on-line unit.
Also, I have checked the log file during the time frame that the Drantez recorded the current spikes and have not seen anything. I was...
There are no static transfer switches fed by the UPS.
The UPS should have transfered to bypass or shown some type of overload condition when these spikes occured, but there is nothing on the UPS log. This is why I am leaning towards the spikes being caused by the UPS.
There was no voltage transient shown in the data. The UPS feeds servers and computers. None of the breakers tripped and they did not have any damage to equipment.
I do not have any idea what might be causing the current spikes. Has anyone had experience with TVSS units "operating" under normal...
On of the building on the campus has been having issues with it's UPS. I decided to install a Dranetz on the output of the UPS to monitor it. The UPS is 225kVA, 480V Input 208Y/120V output. The load on the UPS is about 200A but there have been current spikes at diffrent times.
The first spike...
The distribution system as well as the building is owned by the government. There is a meter for each building located on the transformer.
Would bonding at the transformer prevent objectionable currents from occurring?
The transformer feeds two separate buildings. Originally there was a circuit breaker installed inside the LV compartment of the padmount transformer, which fed one of the buildings. At some point the breaker was removed and the conductors were connected directly to the transformer. I'm guessing...
I was inspecting a 13.8-208/120V pad-mount transformer that serves two separate buildings. The equipment grounding conductors and the grounded conductor(1 for each building) are all bonded together at the transformer. Each building is fed by 3-phase conductors, 1-grounded conductor, and...