lester.cape
Member
- Location
- Las Vegas
Need some help? We are going to install a 112.5 KVA Delta WYE transformer to step up the voltage from 120/208 to 277/480 to power a large piece of equipment. My question is this ( is a indoor type drypack transformer fed from a service disconnect who's power is derived from another transformer still considered and seperately derived system?). I am thinking yes because there is no direct electrical connection between the two voltages other than ground. I think it does need to have a main bonding jumper installed. My co-workers think not because there is already a main bonding jumper in the transformer the feeds the sevice dissconnect that is going to feed this new transformer. I am aware that you can only make this connection at the transformer, meter encloser, or the service disconnect. What do you guys think? Is this second transformer seperately derived from the first. Do I need a bonding jumper or not? If not can someone help me understand how a fault on this peice of equipment could get back to the source if I don't make this connection.