SpecSizer: Streamlining Generator Set Selection

Introduction

Specifying the correct generator set for a project is a critical engineering task. An undersized genset may fail to support critical loads, while an oversized unit leads to unnecessary capital expenditure, inefficient operation, and higher maintenance costs. Finding the optimal balance requires analyzing site conditions, load characteristics, and performance requirements.

To address this challenge, Caterpillar has developed the Cat® Electric Power SpecSizer, a free, web-based generator set sizing tool available globally in seven languages. This tool helps engineers, contractors, and consultants find the right generator set for their specific project needs by providing accurate technical data, consistent load modeling, and optimized algorithms.

A Tool for Every Project

Caterpillar offers two main generator set sizing tools to suit projects of varying complexity:

• The Three-Step Sizer – Ideal for smaller projects, this mobile-friendly tool handles up to 25 loads across one to five load steps and matches sizing output to available inventory units up to 750 kW.
• SpecSizer – Designed for complex or larger projects, SpecSizer has no limit on the number of loads or steps, provides calculated voltage and frequency dips, and allows users to add loads individually, in multiples, or via spreadsheet upload. It also enables saving and sharing of projects and downloading of guide specifications.

Key Features and Capabilities

Advanced Load Modeling

SpecSizer distinguishes itself through its ability to evaluate a wide variety of load types. It includes built-in options for common loads such as HVAC systems, lighting, motors, pumps, elevators, and ultraviolet lights, as well as single-phase IEC and NEMA motors. This depth of modeling ensures more accurate and realistic generator sizing by accounting for load-specific starting characteristics and inrush currents.

Intuitive User Interface

The tool is designed for ease of use, featuring a drag-and-drop functionality to quickly model a facility's load profile. Users can easily organize and sort project files, and the system uses optimization algorithms to calculate the best fit-for-purpose generator set. An updated user interface with a modern, interactive design also enables easy file sharing to facilitate collaboration with Caterpillar experts.

Comprehensive Output and Documentation

Once the load profile is defined, SpecSizer recommends specific Cat generator set models based on the input data. The tool provides a complete sizing report, generator set technical data, and drawings, all available for download. Enhancements have also been added to allow users to download BIM models directly from the platform. Users can also compare different generator models and configurations to evaluate their performance characteristics.

Free and Globally Accessible

SpecSizer is completely free to use. It is available globally and supports seven languages: English, French, German, Italian, Portuguese, Spanish, and Chinese. Access requires a Caterpillar user ID and password, but users can watch a simple introductory video before creating an account.

Support and Application

For technical support with the SpecSizer software, Caterpillar provides a dedicated email address: specsizersupport@cat.com.

SpecSizer is suitable for sizing both stationary and mobile generator sets in the 20 kW to 4000 kW power range.

Conclusion

The Cat® Electric Power SpecSizer is a powerful and accessible tool that simplifies the complex process of generator set sizing. By combining an intuitive interface with advanced load modeling, comprehensive output, and no cost to the user, it empowers electrical professionals to make confident, accurate decisions and deliver reliable power solutions tailored to their specific applications.

This article summarises key concepts about the Cat® Electric Power SpecSizer platform based on information provided by Caterpillar.

Access the full free online tool here: Cat® Electric Power SpecSizer

The tool is free to use, but a Caterpillar user ID and password are required.

References: Caterpillar Inc., Electric Power SpecSizer, Cat.com.