MCC - Summary Tab

The Summary tab of MCC Data dialog box provides the total load on the MCC and the load that must be used in designing.

The Summary tab of the MCC Data dialog box is shown, displaying U.S. units.

Figure 1: Summary Tab (U.S. Units)

The Summary tab of the MCC Data dialog box is shown, displaying metric units.

Figure 2: Summary Tab (Metric Units)

Option Descriptions
Option Description

Calculate Downstream Load

Calculates the total load on the MCC, taking into account the connected load, demand factors, and NEC code factors.

Single-Phase Load Calculations: Load calculations for 1PH equipment follow the conventional load calculation method similar to 3PH systems. The current value in Amps is obtained from the average connected kVA.

For right-most column in the Summary tab (Including Downstream Loads), the apparent power (VA or kVA) of individual downstream loads is summed up first for each energized (hot or live) current carrying conductor. The respective load current is calculated from the voltage for the line of circuit. For each branch circuit tapped off at the distribution point, the program keeps track of the phase connection type. For example, phase connection for 1PH branches could be AN, BN, CN, AB, BC or CA. During load calculations, downstream load values are applied to the correct phases at the upstream distribution point. The results are displayed under the Downstream Load column.

Override with User Values

This check box enables you to enter data in the Total Downstream Load – kVA column.

Stored Results

You can fault buses and store the short circuit current and arc flash results in the database. These results can be displayed in schedules.

The stored results can also be viewed in the Database Browser and Database Report using existing or custom configurations. See Store Short Circuit Results and Store Arc Flash Results for more information.

You can also store the worst case arc flash scenario information from within the Arc Flash Scenario Comparison report. The stored results are displayed here. See Store Worst Case Arc Flash Results for more information.

Spreadsheet

The spreadsheet has two sections – MCC Load and Including Downstream Load.

Option Descriptions
Option Description

MCC Load

This spreadsheet section provides the summary of the loads fed by the feeders of the MCC. The loads from the sub-MCC and sub-panels are not included in this section.

Total kVA

This is the aggregate load.

Total FLA

Total load in amps.

Motor HP

The total HP for the items with "On" in the Status column of the Description section.

Motor kVA >= 50 HP

Motor kVA >= 37 kW

The total KVA for connected items equal to or greater than 50HP (U.S. units) or 37 kW (metric units).

Motor kVA < 50 HP

Motor kVA < 37 kW

The total KVA for connected items greater than 50HP (U.S. units) or 37 kW (metric units).

VFD HP or kW

Variable frequency drive HP (U.S. units) or kW (metric units).

Static kVA

Total kVA of the loads.

Capacitor kVAR

Total kVARs of all the capacitors
(Calculations)

Connected

Connected kVA = [(SkW)2 + (SkVAR)2]1/2

Demand

Demand kVA = [S(kW * DF)2 + S(kVAR * DF)2] ½

Where DF is the individual demand factor of each MCC circuit.

Code Factors

Code Factors kVA = [(kWL + SkW)2 + (kVARL + SkVAR)2]1/2

Where, kWL = Code Mult Factor * kW for largest motor in MCC.

KVARL = Code Mult Factor * kVAR for largest motor in MCC.

kW and kVAR are for the rest of the loads.

The code multiplying factor is specified in Tools > Options > Equipment.

Design

Design kVA = Code Factors kVA * Design Factor

The Design Factor is specified in Tools > Options > Equipment.

Including Downstream Load

This provides the sum of the loads fed by feeders inside the MCC and the sub-MCC and sub-panels.

kVA

Total kVA load calculated. You can enter your own values in these fields by selecting the check box for Override with User Values.

FLA

Total FLA load calculated. You can enter your own values in these fields by selecting the check box for Override with User Values.

More Information