Understanding weights of equipment is very important in estimating. The weight of a piece of equipment determines the following:
- The number of men
- Speed of moving
- Type of tools
- Hoisting method
- Hangers sizes
- Specialty hangers – custom made
Location is important also. Setting a generator at grade level verses placing it on the roof of a 15-story building must be considered.
For example, a 100A NEMA 1 disconnect switch weighs approximately 27 lbs. A NEMA 7/9 100A disconnect switch weights approximately 100 lbs. Sections of switchboards can weight 1,000 lbs to 2,000 lbs., depending on voltage, amperage, and components.
The estimator must understand that the weight and placement of a piece of equipment determines the number of labor hours and any other direct costs.
Obtain the manufacturer’s product data sheet if necessary to know weights and dimensions of the equipment you are estimating.
Remember, estimating is expensive, poor estimating is costly, but quality estimating is profitable.