DOL
A number of methods are employed for starting induction motors as these motors draw more starting current during starting. The high starting current flow causes damage to the windings, hence to prevent this damage different types of starters are employed. Direct on Line (DOL) start is the simplest and most traditional type, here, the motor is directly connected to the power supply performing. The motor is at full load, with full line voltage applied to motor terminals. This causes the motor to draw a lot of current and it is only suitable for motors up to 4Kw, with a maximum motor size of 10Kw. In case, high powered motors are wired as DOL, it causes voltage drop in the supply circuit.
This system is considered to be the most cost-effective system for starting pumps and motors. Such type of set up is suitable for startup of small submersible pumps, deep well pumps, or booster set with surface pumps. In short, it is well suited for stable supplies, mechanically stiff and well dimensioned shaft systems and pumps. It is the most common starting method and it actually gives lowest temperature rise within the motor during start up.
Benefits of DOL
There are a couple of benefits associated with the direct on line systems which can be summarized as below
- It is the most economical starter which is simple to operate.
- It is more comfortable to operate and control.
- It provides a high starting torque.
- It starts at full voltage and constant frequency.
- It displays short acceleration times.
- The system is easy to understand and overhaul.
Star Delta Panels
When sizeable induction motors are started direct on line, they cause a disturbance of voltage on the supply lines due to large starting current surges. To limit these surges, reduced voltage is used to start the large induction motors and then have full supply voltage reconnected when they run up to near rotated speed. Star delta is one of the methods used for reduction of starting voltage. Two contactors are being used by star-delta, one to start at a lower voltage in star and the other to run at a high voltage in delta configuration.
The proportion of starting current is three times less with the use of star delta panels. Star delta is one of the best known and most widely used low voltage starting method. In case with the functioning of pumps, it is used to start the pump’s motor with lower levels of mechanical stress.
Benefits of star delta panels
There are a number of benefits associated with the use of star delta panels which can be summed up as under
- The functioning part of star delta panels is tough ,but, is simple to understand.
- In comparison with other reduced voltage methods, this type is relatively cheap.
- Good current performance.
- The main advantage is reduction if power supply during starting of the motor.
- The efficiency of the panel at the time of functioning increases and little heat is produced.
Why Vedant Electricals
Vedant Electricals is a unique name in the field of manufacturing and supplying DOL and star delta panels. We provide export quality of both these panels available within the industry. Our well experienced and trained staff clearly follow the guidelines and the norms as set up for production of both types of panels. With the help of our well-equipped and high tech unit, we are able to manufacture and supply high quality panels for use by our customers. We pay special attention to the process of delivery of our panels as well as the installation and servicing of our panels. We have designed our unit in a manner that we can easily manufacture orders in bulk quantities and satisfy the requirements of our customers.