The following diagram shows fuses off each of the PT connections (standard IEC fuse symbol) but it also shows a fuse symbol with inverted colouring on the neutral connection.
This second fuse also looks like the IEC fuse but what is the reasoning for the colour inversion? Is there a special neutral fuse that no one has told me about?
- GE 869 Motor Protection Relay
- Schematic is from this manual. PDF page 42, manual page 2-8.
- PTs connected in wye configuration (shown above)
- PTs and fuses are external (i.e. not included) to the motor protection relay.