RECURSOS DIDÁCTICOS

The Schedule Subview, shown in the following figure, is the same for all three types of schedules. Select or type the data you want for the schedule in the Schedule Subview.

Tip: When you select the Schedule Category type (Panel, MCC, or Switchboard), the second subview in the Components Subviews box automatically changes to match the schedule type. Therefore, it is a good habit to always select the Schedule Category first. That way, you won’t inadvertently proceed to the incorrect second subview.

Each box and its available options are listed in the following table:

In this box Type or select this data

Name: 14 character name; PTW-assigned name may be used.

. . .corresponds to the schedule type you choose here. This subview name. . .

In this box Type or select this data

In Service: Checked for In Service, left unchecked for Out of Service.

OC (Overcurrent) Device Type: Breaker, Fuse, MOL (Motor Overload), or your own description.

Mounting: Flush, Surface, Free Standing, or your own description.

Device Family: Bolt On, Plug In, Draw Out, Plug, Cartridge, or your own description.

Enclosure: NEMA 1, NEMA 3R, NEMA 4, NEMA 7,

NEMA 9, NEMA 12, or your own description. Continuous Current Rating, Busbar: Full-load current rating.

Withstand Rating, Bus SC: Maximum short circuit rating.

Schedule Specification: 3-Phase 3-Wire, 3-Phase 4-Wire, Single-Phase 3 Wire.

Schedule Category: Panel, Switchboard, MCC, or Single-Phase Panel.

Notes: Custom notes.

Mains: Reads breaker size of nearest upstream breaker in Fed From branch. Also allows user direct entry.

Fed From: Defines the upstream bus feeding the schedule. Options included the connected bus and all buses one away from the schedule bus. Connections. . . Changes the component connections.

4.22.2. Panel, MCC, or Switchboard subview

This subview changes slightly depending on the Schedule category chosen in the Schedule subview. All three are used to assign load descriptions to the schedule, but the Panel assigns them in the form of circuits, which display the separate phases A, B, and C for the circuit, while the MCC and Switchboard assign them in the form of cubicles, which do not show the separate phases. For example, let's say you assigned Transformer 1 to a schedule. If the schedule is a panel schedule, you will see the transformer at all 3 phases of the circuit, whereas if the schedule is an MCC or switchboard schedule, you will only see the transformer at the one cubicle:

Panels show all three phases of the circuits. MCCs and switchboards show the three phases as one cubicle.

Assigning Bus Loads and Sub-Feeds to the Schedule

To assign an existing load (induction motor, synchronous motor, or non-motor load) or sub-fed impedance device (cable, transformer, transmission line, or pi impedance) to a schedule, highlight the load or impedance device in the Available Loads at the Bus box.

Next, highlight an available cubicle/circuit. Lastly, click the Connect to Circuit (or for MCCs and switchboards the Connect to Cubicle button).

For panels, highlight an available bus load, then highlight an available circuit, and click the

Connect to Circuit button.

For MCCs and switchboards, highlight an available bus load, then highlight an available cubicle, and click the Connect to Cubicle button.

The load disappears from the Available Loads at the Bus box and appears next to the circuit, representing the connection. PTW assumes existing loads and impedance devices are three-phase and therefore they occupy all-three circuits in the schedule.

To break the connection, click the Remove button.

To add protective device data to an impedance device or non-motor load that is connected to a cubicle/circuit, highlight the cubicle/circuit, click the Modify button, and type an Overcurrent Protection size:

If you click the Ind Mtr button _{or the Synch Mtr button PTW} actually creates a new motor (exactly as if you clicked the _or button) and connects the motor to the schedule's bus. You will see the motor in the Component Editor, but you won't see the motor on the One-Line Diagram unless you add its symbol using the Component>Existing command.

Important: If you have a motor symbol on the One-Line Diagram which represents more than one motor, and you select that motor symbol from the Available Loads at the Bus box, the schedule treats it as only one motor. Therefore, if you want to model multiple motors in the schedule, it is best to assign only one motor to the motor symbol when you create the component. You can then Clone it as many times as you want, attaching each motor to the bus, so that you have the desired number of motors. You can then assign each motor to the schedule individually.

To assign additional data to a motor, click the Modify button, which displays the Motor Schedule Data dialog box. The Motor Schedule Data window has four different tabs: Motor Control, Impedance, Sizing, and Cable Key.

Motor Control Tab

The Motor Control tab, shown below, allows you to assign a motor name, size, and a library reference for overcurrent protection and starter information:

Each data field, and the available options, are listed in the following table:

In this box Type or select this data

Name: 14 character name; PTW-assigned name may be used.

Rating: Motor size in HP, kVA or kW (same as motor rating in Component Editor).

Motor Library Key: If set to <User Defined>, uses Rated Size; if a value is selected, references Motor Library to automatically assign overcurrent protection and starter information.

Rated Size: (only appears when Motor Library Key is set to <User Defined>)

Rated size as stored in the Motor Library.

— or —

Voltage Range/Starter: (only appears Required to complete the Motor Library Key.

Select the Motor Control subview by clicking on its tab.

Type or select data for the new motor.

In this box Type or select this data

when Motor Library Key has a value selected. Not shown in the preceding figure)

Voltage Range and Starter entries must be defined in the motor library to be displayed in this field.

Overcurrent Protection Not editable if a Motor Library component is selected. May be changed if Motor Library Key is set to <User Defined>. Text boxes include Type, Size and Poles.

Starter Not editable if a Motor Library component is selected. May be changed if Motor Library Key is set to <User Defined>. Text boxes include Type, Space, Size and Accessory Group. Library FLA: Not editable if a Motor Library component is

selected. May be changed if Motor Library Key is set to <User Defined>. Motor full load amperes as defined in the Motor Library. The Library FLA may reflect a standard NEC value and may not match the actual motor rating. The motor demand and design load values are calculated using the Library’s FLA value. If the FLA is zero, the Demand Load Study calculates this value based on the motor rated size. See the Demand Load Study chapter of the Reference Manual for further details and examples.

Impedance Tab

The Impedance tab, shown below, is linked to the Cable Library, and allows you to assign a cable size from a MCC schedule to the motor. The cable impedance is used to calculate the branch circuit voltage drop shown on the schedule input and output. The impedance is not used in the full system load flow and short circuit study modules:

Each data field, and the available options, are listed in the following table : Select the Impedance subview by clicking on its tab.

Type or select Impedance data for the new motor.

In this box Type or select this data

Cable Library Key: Selected size uses Cable Library’s impedance value. If you do not want a Cable Library link, or if you want to edit impedance values after the initial Library link, Click the Library button followed by the Deselect button.

Cable Size: May be changed if Library Key is set to <User Defined>. Limited to standard library sizes when Cable Library Key is specified. Length: Length in feet or meters (as selected in Project

Options).

Impedance: Not editable for cables referenced from Cable Library. May be changed when Cable Library Key is set to <User Defined>. Units in Ohms per 1000 feet or meters (as selected in Project Options).

Conductors in Parallel/Phase: Number of parallel conductor per phase. Per Unit Conv… Per unit conversion dialog box to assist with per

unit conversions if Cable Library Key is set to <User Defined>.

Sizing Tab

The Sizing Tab, shown below, is also linked to the Cable Library and displays ground wire size, rated ampacity, neutral size, design ampacity, duct bank specification,

temperature and raceway specifications. Most of the fields are not editable when a Cable Library Key value is selected in the Impedance Tab. All of the fields may be changed when the Cable Library Key is set to <User Defined>.

Each data field, and the available options, are listed in the following table:

In this box Type or select this data

Ground Size (No Parallel): Ground wire size for a single conductor.

Select the Sizing subview by clicking on its tab.

Type or select Sizing data for the new motor.

In this box Type or select this data

Rated Ampacity: Ampacity rating with no duct bank or temperature derating.

Neutral Size: Neutral conductor size.

Ground Size (Parallel): Ground wire size for multiple parallel conductors. References the Cable Library’s Ground Wire Sizes for Number in Parallel Subview when a Cable Library Key value is selected in the Impedance Tab. See the “Libraries” chapter to view or edit the Cable Library Subview.

Duct Bank Detail: Ampacity based on pre-defined duct bank configurations. The library defaults use NEC detail drawings.

Design Ampacity: Cable ampacity adjusted for duct bank configuration.

Temperature: Temperature derating table.

Derating Factor: Temperature derating factor as defined for the specified temperature in the temperature derating table.

Number of Raceways: Number of raceways for the branch circuit, usually assumed to be one for each set of conductors.

Circuit Description: 3 Wire, 3 Wire+Grnd, 4 Wire, or 4 Wire+Grnd.

Type: User-defined description of raceway.

Size: User-defined size of raceway.

Cable Key Tab

The Cable Key Tab, shown below, is the last of the four tabs in the Motor Schedule Data dialog box. The Cable Key Tab is only used when the Cable Library key in the

Impedance Tab is set to <User Defined>, and you want to assign a cable description: Select the Cable Key subview by clicking on its tab.

Each data field, and the available options, are listed in the following table:

In this box Type or select this data

Voltage Rating: Maximum voltage rating of the cable. Duct Material: Magnetic, Non-Magnetic, Bus, or Plastic. Conductor Type: Copper or Aluminum.

Insul Type: Insulation (for example, THWN, THHN, XLP, EPR, etc.)

Adding Little Loads to Circuits

"Little loads" are one-, two-, or three-pole loads (such as lighting) that you can assign to circuits or cubicles in a load schedule. The big difference between motor and non-motor loads and little loads is that motor and non-motor loads appear on the One-Line Diagram and can be searched for using Queries, whereas little loads do not appear on the One-Line Diagram (you only see them in the Panel, MCC, or Switchboard subview) and cannot be searched for using Queries. Little loads affect the system just as non-motor loads do, so they will affect the results of studies such as Demand Load and the Load Flow studies, and they will appear in the load schedule reports.

To add a new little load to the panel schedule, select an available circuit from the Circuit, Phase, and Description box and, under Load, click either the 1 Pole, 2 Pole or 3 Pole button. The Schedule Load dialog box, as shown below, appears:

Type or select Cable Key data for the new motor.

Each data field and the available options are listed in the following table:

In this box Type or select this data

Description: 14 character description; PTW-assigned description may be used.

Rated Size: Load size in VA, kVA, kW, or Amps. Quantity: Number of loads at the rated size.

Power Factor: Power factor in per unit (Unity), leading (Lead), or lagging (Lag).

Demand Category: Load category from Demand Load Library.

Notes: Personal notes.

Overcurrent Protection Size: Protective device size in amperes.

To copy existing circuit data to a blank circuit, select the circuit you want to copy from the Circuit, Phase, and Description box, and choose the Copy button; this copies the circuit to the clipboard. Then select a blank circuit from the Circuit, Phase, and Description box and choose the Paste button. The copied circuit is then pasted to the blank circuit. This lets you quickly create a complete schedule. (Only little loads can be Copied and Pasted. Use the Clone command in the One-Line Diagram to copy an load or impedance device.)

Note: While panel schedules let you model single-phase loads and report the load on each phase, the Demand Load and Load Flow Studies use the equivalent three-phase load.