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I was given a coil that picks at 65% of rated voltage which is 115 V. If I want to perform calculation on 120 V basis, how would I correct the pick up voltage. Thanks Yigo

I am trying to find out if there are tests data that show the impact of grounding conductors as determined per NEC Table 250.122 on zero sequence impedances of cables. Thanks Yigo

All, I am trying to use Eaton breakers type HFD in a 125 VDC system ungrounded. The breakers have an Interrupting Capacity Rating listed for 250 VDC but not for 125 VDC. I would like to know potential risks for the application. Thanks Yigo.

All, Breaker TCC and damage curves are plotted for one line diagram section that has a transformer 480V Delta/208V Wye-Grounded, a breaker at the transformer primary and cables. The plot time axis current is referenced to 208V,and short circuit current for 3 phase fault and phase to ground have...

I was reviewing IEEE C37.91 when I found the enclosed coordination steps. I am wondering what is the meaning of the symbol >>? Is this a typo? Thanks for your consideration. Yigo...

All, Please explain to me the impact of the thermal overload relay current setting range. I have a relay with the following current settings: 85%, 100%, 115%. If at 100% setting, the relay trip at t100, what would be the trip time at 85% by just adjusting the current dial. Likewise, what would...

All, I have a 208/120V, 3Ph, 4W lighting panel. I want to list a 1Ph 208V, 1000W connected between phases 1 and 2. I think the right way is to list 1000w for each phase 1 and 2. Please advise if this is right. Thanks for your input. Yigo

Hi Everybody, Please let me know if it is required, advised or not advised to seal conduits when they enter or exit the manholes. I would appreciate any reference material on this subject. Thanks, Yigo

Hi, We are replacing GSU transformers. The new ones are taller than existing. I am wondering if anybody is aware of issues related to GSU tansformers clearances to the HV line. The new transformers contain also more gallons of oil. I am wondering if anybody is aware of issues related to the oil...

Hi everybody, I am looking for references on how to size a battery disconnect switch. Any help will be appreciated. Thanks, Yigo

Hi All, I'd like to know if a circuit protected by a GFCI breaker is required to have a ground wire. thanks, yigo

Hi Everybody, During traction power substations surveys, I noticed that there are more cables between the DC positive bus and the third rail than cables between negative DC bus and the track.Both cables positive and negative are identical. Can anybody help me understand? Thanks. Yigo

Hi everybody, I am thinking about how to assess the physical condition (cleaness, available space, ...) of an existing duct (20+years old) spare or not. Could anyone give me a convenient way to do so. Thanks for your consideration. Yigo

Hi everybody, I am an EE and I am involved in duct banks estimations. I need to know how to assess rebars quantity for a given concrete defined area. Thanks for your consideration. Yigo

Hi everybody, Instanteneous elements are sett off on 480V switchgears and MCC circuit breakers except for VFD CB in a power plant. Does anybody know what may be the reasons? Thanks. Yigo