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SWL or WLL are calculated by **dividing MBL by a safety factor (SF)**. An example of this would be a chain that has a MBL of 2000 lbf (8.89 kN) would have a SWL or WLL of 400 lbf (1.78 kN) if a safety factor of 5 (5:1, 5 to 1, or 1/5) is used.

**Multiply the mass of the object by the gravitational acceleration of the earth (9.8 m/sec2)**, and the height in meters. This equation is the object at rest’s potential energy. Potential energy is measured in joules; this is the load force.

- Step 1: Determine the Volume of the Load. Rectangle/Square: Volume = Length x Width x Height. …
- Step 2: Determine the Material You’ll Be Lifting. The table below can be used for approximate weight values of common loads and materials: …
- Step 3: Determine the Weight of Object.

Working Load Limit (WLL) is the maximum **working load designed by the manufacturer**. This load represents a force that is much less than that required to make the lifting equipment fail or yield. The WLL is calculated by dividing MBL by a safety factor (SF).

To calculate the required wattage rating needed to supply the subpanel, **multiply the total wattage (from the square footage and appliance calculations) times 1.25 to** get the adjusted load. This safety adjustment is required by the National Electrical Code and provides a buffer for voltage drop on the feeder circuit.

The type of scaffolding being used is rated as light-duty, or **25 pounds per square foot**. Multiply 35 square feet by 25 pounds per square foot and the scaffolding can be loaded with no more than 875 pounds.

Calculating an Electrical Load in a Simple Circuit **Let Power = Voltage * Current (P=VI)**. Let Current = Voltage/Resistance (I=V/R). Apply Kirchoff’s Second Law, that the sum of the voltages around a circuit is zero. Conclude that the load voltage around the simple circuit must be 9 volts.

- Calculate the weight of a steel plate (shown in figure 1) 2ft wide X 5ftlong X 1inch (0.0833ft) thick.
- Use the formula:
- Volume = Length X Width X Height.
- Unit weight of steel is 490 lbs/ft³
- Volume = 5ft X 2ft X 0.0833ft X 490 lbs/ft³
- Weight = 408.3 lbs.

Written By Rachel Novak It is a **calculation of the Minimum Breaking Strength, or MBS**. … For example, if a hook has a Minimum Breaking Strength (MBS) of 1,000 pounds and a safety factor of five, then the Working Load Limit (WLL) would be 200 pounds.

Although tensile strength is a definitive quantity measuring the force required to break a rope, working load limit is a measure that takes a wide range of variables into account. And always, **the tensile strength of a material is greater than the recommended working load limit**.

The working load limit of a rigging **system is equal to 1/3 the amount of the break strength**. As such, a strapping system with a working load limit of 5,000 pounds has a break strength of 15,000 pounds. Remember, the working load limit will determine how much you should allow the system to hold, not the break strength.

2 Answers. Can you add a 100 amp breaker to your main panel? **Yes you have 12 slots** the double pole breaker will only take 2 slots.

A 60A/2P circuit would make a nice sub-panel for your basements or garage. If you have a 60 amp service you could probably put **2 20 amp breakers for outlets and 2 15 amp breakers for lights**. If all 4 circuits are near max, your 60 amp main circuit breaker will trip. If you use 20 amp breakers, you need to use 12 ga.

You can feed a 100 Amp panel with a 60 Amp breaker. Keep in mind that the **sub panel needs to be rated above the breaker size**.

**Divide the total height measurement by the height of a single scaffolding section**. This will determine the total number of rows of scaffolding the project will require. Multiply the number of rows by the number of columns to find the total number of scaffold sections necessary for the project.

The theoretical weight calculation formula of scaffolding tubes is **(out diameter-wall thickness) X wall thickness X length X 0.02466 (kg)**

They are: **Light Duty – 25 pounds per square foot**. Medium Duty – 50 pounds per square foot. Heavy Duty – 75 pounds per square foot.

We find the power in kilowatts P(kW) by dividing the power in watts P(W) by 1,000. Here’s the Formula for Converting Watts Into Kilowatts: **P(kW) = P(W) / 1,000**.

- Volume of Concrete = 0.23 x 0.60 x 3 =0.414m³
- Weight of Concrete = 0.414 x 2400 = 993.6 kg.
- Weight of Steel (1%) in Concrete = 0.414x 0.01 x 8000 = 33 kg.
- Total Weight of Column = 994 + 33 = 1026 kg = 10KN.

When calculating motor loads, you need to know how to convert a motor’s current rating (given in amps) to a VA rating. To do this, **multiply the motor’s nameplate amperage by the supply voltage.**

1 a measure of the heaviness of an object; the amount anything weighs. 2 (Physics) the vertical force experienced by a mass as a result of gravitation. It **equals the mass of the body multiplied by the acceleration of free fall**.

Formula: **SWL (kg) = D2(mm) x 8** For example: Rope dia (D) = 12 mm SWL (kg) = D2 (mm) x 8 = D (mm) x D (mm) x 8 = 12 x 12 x 8 = 1152 kg SWL (t) = 1.15 tonnes The above equation can be reversed to calculate the diameter (D) in millimetres of FSWR needed to lift a given load.

Once you know the diameter of the rope, you can apply it to the formula, which is **SWL = D2 x 8**. D represents the diameter of the rope in inches. If you’re working with a 1.5-inch diameter cable, for example, then the formula would be SWL = 1.52 x 8 or SWL = 2.25 x 8.

For example, 10,000 pound breaking strength of force before failure would result in a **3,333 lb working** load limit. This allows for extra fail safes to be put in to place to keep you and your load safe.

Tensile strength It is defined as the amount of tensile stress a material can withstand before breaking and denoted by s. The formula is: **σ = F/A**. Where, σ is the tensile stress. F is the force acting.

a) the tensile strength, also known as the ultimate tensile strength, the load at failure divided by the original cross sectional area where the ultimate tensile strength (U.T.S.), **σ max = P max /A 0** , where P max = maximum load, A 0 = original cross sectional area.

Rope DiameterSafe Load (Safety Factor 12)(in)(mm)(lbf)1/2124739/16146005/816**743**

The minimum breaking load **describes the maximum force under straight pull a free length of rope can be exposed to until it breaks**. It is specified in daN or kN. The minimum breaking load for ropes required under EN 1891 A is 22 kN.

**Yes**, any sub panel outside of the main building requires it’s own ground rod and a ground wire back to the main building. And yes, a sub panel in the same building as the main does not need a ground rod – only the ground wire.

No. It is **100 amp**. And the two 50 amps breakers that are tied together are 50 amps, not 50 + 50 = ! 00.

As the panel is rated at 100 amps the 50 amp breaker **can be used for any circuit in the panel**. However, everything on the circuit would then need to be rated for 50 amps or better. Few circuits require 50 amps and most of the equipment in your house is not rated for it.

A **main breaker** is the same as any double breaker in the box, except that it supplies power to each busbar. The answer is no if you want to draw 60 Amps off a 30 Amp double breaker.

A small, 60-amp fuse box might be found in an older home that has not had its wiring upgraded. It can supply power to only one 240-volt appliance, such as an **oven or a clothes dryer**.

The size of a sub panel for a workshop should be a **minimum of 60 amps up to 100 amp** power feed from your house or main service. This is assuming that you have at least a 200 amp main service.