Pro Support

Blog/News

How to choose the right cable ladder

Cable ladders are essential components your project may need if you’re looking for a cable routing system. Since there are many different types, including the Nema 1, Nema 2, Nema 16a, and Nema 20b cable ladders, it’s not easy to select the correct cable ladder. To make the right choice, you need to know specific information about the cables and understand how cable trays are different from cable ladders. Your goal is to select the correct cable ladder for your project – to do so, you’ll need to know which specific cable ladders are available and their properties. This Pro Support Solutions article will outline the critical properties of cable ladders and how you can select the right one for your project. How to choose the right cable ladder

What is the difference between a cable tray and a cable ladder?

Cable ladders comprise multiple rungs used to support heavy cabling that has significant spans between each support. On the other hand, cable trays are a preferred option for less industrial-grade projects, tubing, and supporting instrumentation. Cable ladders are designed with parallel rails that are linked with rungs and set out at equal intervals. If you need to use cable ties with cable ladders, you’ll have no problems, and your wires will also benefit as there is hardly any moisture or dust accumulation. Cable trays don’t have the rungs that cable ladders have. They are one sheet of metal with slots that are arranged in patterns. You can also use cable ties with cable trays, and this type of cable support is ideal for electromagnetic interference mitigation.

What are some different types of cable ladders?

Some of the main types of cable ladders include Nema 1, Nema 20b, Nema 16a, and Nema 2. Here’s more information on each of these cable ladder types.

What is the Nema 1 cable ladder?

The Nema 1 cable ladder is a cable ladder that’s ideal for supporting cable lengths that span 1.5 meters and weigh approximately 248kg per meter. You can also use a Nema 1 cable ladder for supporting cable lengths that span three meters and weigh about 112kg per meter. Depending on your requirements, you can opt for the three-meter-long Nema 1 ladder or the six-meter-long option. The Nema 1 cable ladder has a cabling loading depth of 43 millimeters. 

What is the Nema 20b cable ladder?

The Nema 20b cable ladder is ideal for supporting cable lengths that span six meters and weigh 112kg per meter. Keep in mind that the cabling loading depth of the Nema 20b cable ladder is 109 millimeters.

What is the Nema 16a cable ladder?

The Nema 16a cable ladder is ideal for supporting cable lengths that span six meters and weigh 79kg per meter. It’s also crucial to keep in mind that the cabling loading depth of the Nema 16a cable ladder is 72 millimeters.

What is the Nema 2 cable ladder?

The Nema 2 cable ladder is perfect for supporting cable lengths spanning four meters and weighing 113kg per meter. Keep in mind that the cabling loading depth of the Nema 2 cable ladder is 75 millimeters.

How do you choose cable size from the current rating?

You can effortlessly calculate and choose the correct cable sizing by using the following calculation:
  • Cable sizing = voltage through cable / target current
Here’s an example of this calculation. If the cable’s voltage is 180 volts and the target is 60 volts, divide the voltage by the target current (180 / 60). This will give you a target resistance of 3, which you can match to the required cable size. How to choose the right cable ladder  

How do I choose the suitable cable?

When selecting a cable, you have three factors to think about: the cable’s maximum current capacity, voltage regulation, and the short circuit rating. 

1.  Note the maximum current that the cable can withstand

When noting the maximum current that the cable can withstand, remember that larger cable cross-sections will result in less loss in current resistance. For this reason, you may want to select cables that have bigger cross-sections.

2.  Work out the voltage drop

See the formula below to determine the voltage drop, which is essential because as the current flows, it’s essential to factor in the change in voltage:
  • Voltage drop = voltage drop per meter for each ampere x circuit conductor length x current / 1000

3.  Determine the conditions for short-circuiting

Since high currents can damage cables, it’s essential to consider the conditions for short-circuiting to determine the minimum cable size. Use the following formula to determine the minimum cable size:
  • Minimum cable size = √(short circuit current2 x time for the short circuit) / short circuit temperature

4.  Use the calculated values in steps one to three to calculate cable size

Finally, take all the values you have calculated in steps one to three and use a cable size calculator to determine the correct size cable. How to choose the right cable ladder

What is the maximum distance allowed between cable supports?

For your project, remember that the cable supports should not exceed 1.37-meter intervals, especially if the wiring is a permanent installation. You must also install them 305 millimeters from each cabinet or fitting.  If the cable is a temporary installation, you must secure it in a way that guarantees it’s protected from equipment or crew members. This measure is essential for the safety of your team members and for passing inspections.

Choose the right cable ladder for your project

Choosing the right cable ladder for your project will require you to understand the project’s requirements and the properties of each cable ladder. Now that you’re aware of the many cable ladders available, such as the Nema 1 cable ladder, Nema 2 cable ladder, Nema 16a cable ladder, and Nema 20b cable ladder, you can start deducing which ones have the suitable properties for your project. Go to Pro Support Solutions and look at the components we supply to install your cable ladder the effortless way. Choose incredible component quality. Choose Pro Support Solutions and MEFA.

Hear about our new and innovative products within the renewable energy, pipe and cable support industries.

Recent News