Design Master December 2012 Newsletter

Table of Contents

• Updated Electrical Documentation Released
• Updated Equipment Breaker and Wire Sizing
• Customer Story: Misean, Inc. Goes from Startup to Success

Updated Electrical Documentation Released

The documentation for Design Master Electrical has been revised and updated for the latest release of the software.

View it on our website.

Download it to update the local copy on your computer.

We are continuing to work on updating our documentation for Design Master HVAC and Design Master Plumbing.

Updated Equipment Breaker and Wire Sizing

In Design Master Electrical 8.0, we added MCA and MOCP and used them to size Breakers and Wires for equipment connections. Since then, we have worked with a number of customers to refine this feature. In the patch we released earlier this week, we made what we hope are the final changes to it. Even though this change was in a minor patch, it is significant enough that we wanted to highlight it in this month's newsletter.

The new options for equipment are described below. A new field, FLA / BCSC, was added. New choices for Breaker Size and Wire Size were added. These new features were added to better support NEC 430 and NEC 440.

FLA / BCSC: Full load current or branch-circuit selection current. It is used to size the breaker according to NEC 430.52 and 440.22, depending upon the Breaker Size selection. It is also used in one of the Wire Size options. (This field is new in this release.)

MCA: Minimum circuit amps. This is used to size the conductors. It is not used in any of the calculations for the breaker size. (This field previously existed.)

MOCP: Maximum overcurrent protection. Use when sizing motor-compressor breakers, but not when sizing motor breakers. (This field previously existed.)

Breaker Size: How the breaker for the equipment is sized. (This field previously existed but now has more choices.)

• Motor-Compressor, MOCP (or loads if no MOCP). Breaker will be sized to match the MOCP. The FLA / BCSC value will be ignored. If no MOCP value is specified, the breaker is sized based upon the connected load of the device.
• Motor-Compressor, 175% of FLA / BCSC, not to exceed MOCP. Breaker will be sized based upon 175% of the FLA / BCSC value. If that is larger than the MOCP, the MOCP value will be used. This is for NEC 440.22(A).
• Motor-Compressor, 225% of FLA / BCSC, not to exceed MOCP. Breaker will be sized based upon 225% of the FLA / BCSC value. If that is larger than the MOCP, the MOCP value will be used. This is for NEC 440.22(A).
• Motor, Dual Element Fuse, 175% of FLA. Breaker will be sized based upon 175% of the FLA / BCSC value. This is for NEC 430.52 dual element fuse breakers.
• Motor, Dual Element Fuse, 225% of FLA. Breaker will be sized based upon 225% of the FLA / BCSC value. This is for NEC 430.52 dual element fuse breakers exception no. 2 (b).
• Motor, Inverse Time Breaker, 250% of FLA. Breaker will be sized based upon 250% of the FLA / BCSC value. This is for NEC 430.52 inverse time breakers.
• Size based upon loads. Breaker will be sized based upon the connected load of the device.
• Specific breaker sizes. A list of all the possible breaker sizes for manually setting the breaker size.

Wire Size: How the conductors for the equipment are sized. (This field previously existed but now has more choices.)

• Motor-Compressor, MCA (or loads in no MCA). Conductors will be sized based upon the MCA. This is for NEC 440.33 and 440.35. If no MCA value is specified, the conductors are sized based upon the connected load of the device.
• Single Motor-Compressor, 125% of BCSC. Conductors will be sized based upon 125% of the FLA / BCSC value. This is for NEC 440.32.
• MOCP. Conductors will be sized based upon the MCA.
• Size based upon loads. Conductors will be sized based upon the connected load of the device.
• Specific wire sizes. A list of all possible conductor sizes for manually setting the conductor size.

Customer Story: Misean, Inc. Goes from Startup to Success

Our customer story for December is Misean, Inc., an electrical engineering consulting startup based in San Diego, CA