Advantages of Higher Voltage Wiring:
- Running motors at 460 volts results in lower current, reducing temperature rise.
Data Plate Information:
- The data plate on a compressor provides voltage, current, and temperature specifications.
Copeland Diagram:
- Located inside the compressor control box, showing internal wiring and connections.
Using Two Contactors:
- Reduces inrush current to manage large starting currents effectively.
- Diagrams also provide a legend for component designations.
Wiring Options:
- Across the Line Starting:
- Suitable for 208 to 230 volts or 460 volts.
- All power comes from one contactor.
- Connections for Two Line Start:
- Contactors at the top, motor winding connections at the bottom.
- Brass jumpers placed between specific terminals to configure windings in series.
- Exploded view shows terminal box and brass jumpers.
Part Winding Start:
- Required for larger motors (typically over 25 HP).
- Reduces inrush current to prevent high power draw and electrical damage.
- Splits the motor into two sections with two contactors and a one-second delay between them.
- Results in half the starting current compared to across-the-line starting.
Electrical Symbols Legend:
- Provides abbreviations for each component in the circuit.
Control Circuit and Protection:
- Typically includes a protection module and two contactors.
- Time delay relay (TDR) ensures a delay between energizing the two contactors.
- Ensures gradual power-up, reducing inrush current.
Part Winding Start Connections:
- Terminal box with power contactor one (C1).
- Brass jumper bars across specific terminals.
- Second contactor (C2) with time delay relay to energize after a delay.
- Diagrams show how contactors and jumpers are connected.
Commercial Applications:
- Used in larger commercial systems.
- Ensures smooth startup and protection against electrical overload.
Condenser Fan Control:
- Open store contacts power outdoor fans.
- Fans cycle on and off based on system requirements.
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