Depth of Burial Trenching Plowing
Underground installation of systems is a trendy method because of its many benefits. But putting the cables in the ground is not a thing just to come by, do and think it will run all fine. It is required of you to know a lot before you start plowing, trenching and burying the electric cables in the ground. The depth of your plow or trench where you plan to lay the cables is must be taken with a lot of caution because it matters. You will be obliged to choose either of the following methods of underground installation for your work:
i. Direct burial which involves laying of the cables as they are in the ground. Majorly the heavily armored cables are resilient enough and are appropriate for direct burial.
ii. The duct method where cables are housed in a duct under the ground. The duct serves as a protective mechanism for the vulnerable cables.
Depths of Cable burial
The cable used has to get sure protection as possible therefore the distance between the surfaces and where the cables are laid must be deep enough to guarantee protection to the buried cables against any mechanical damage. The depth has not to be too deep to inconvenience the servicing practices which may be required. The amount of voltage that is supplied by a phase also determines the depth of the burial. Cables with high phase voltages are buried deeper than those with lower phase voltages. When creating the burials ensure you make it in a way that is appropriate and relevant for the conductors. Some of the essentials that you ought to master in digging the burial are as follows:
- For the street light cable which operate on a phase voltage of 150 volts or less, the depth of the burial should be very less, around 400mm.
- In case you have a supplementary protection for the conductors, you are good to dig lesser depths. Only ensure the supplementary protection is reliable.
- Cables are easily damaged when exposed to frosts therefore areas with this condition need deeper depths of cable burials.
This is making of trenches which forms the cable raceways. The trenches have to be made to standard. Ensure the base of the trench is done for a smooth touch, everything is well leveled and a tampering is done using smooth sand. A good trench guarantees easy installation and proper cable protection against damages. The trench should not contain any chemical or material that is harmful to the cables. Once a cable is installed, a protective sign should be placed on top to indicate the presence of underlying cable, this prevents excavators from causing damage to the cable.
There are instances where a machine with a vibrating blade cuts the ground at some narrow desirable size and a cable or a duct is laid, this is what is called cable plowing. It helps in reducing disturbance on the ground. It should however be done such that the cables are not damaged from overwhelming tension or exceeding sidewall pressure.