explosion proof motor

An electric motor will generator big electric current during starting; the sudden current may cause sudden voltage drop down, and cause other unexpected bad effects, or damage the equipment. So it’s important and necessary to choose the suitable starting method for functional and cost-effective control system.

Direct online (DOL) starter
Direct online starter is the simplest and cheapest way of electric motor starting. Magnetic starter control panels is the post popular type of Direct online starter. DOL starting is simply switching the motor on in one operation, with a direct connection from the power source. But it can only be used for small motors. For oil and gas drilling mud systems, only the motors less than 30kw will use DOL starting. For big power motors, if there is already an effective control to start and stop the motor, a DOL starter can be used as the second control.

Star-delta starting
In oil and gas drilling field, start-delta starting are normally used for motors between 30kw to 75kw, like for pumps. When we mentioned star-delta starter, the motor is first connected in ‘star’ configuration, which allows the motor to gather speed without drawing excessive current. Once the motor is up to speed (or a preset time is elapsed) it is then connected in the normal ‘delta’ configuration. This method can reduce the starting current demand by 30%, but is only suited to applications where the motor is starting without load .

Soft starting
Soft starters are more expensive than DOL and star-delta. A soft starter is an electronic components which controls the voltage flowing to the motor when startup. Soft starter can slowly increase the supply voltage to the motor, and start the motor smoothly without overcurrent.

Variable frequency speed drives (VFD control)
A variable frequency speed drive (VFD), also known as a VSD or VVVF, which allows complete control of the motor speed including starting and stopping. It operates by changing the frequency of the power supplied to the motor. And the motor can be run at any speed, so VFD drive control can save power, and control the driving speed. Variable frequency drives are the most expensive method for motor starters. And it can be used to control running speed of the machine, like for decanter centrifuges, vertical cuttings dryers, screw conveyors, etc…

In oil & gas field, have to use explosion proof motors in hazardous areas, and in China, usually choose YB2 series. And China also have a lot of world famous motor manufacturers.

YB2 explosion proof motors

Though some world famous motors like ABB, WEG, also have office in China, and Siemens also have invent in Siemens Beide, now we are going to introduce some local companies. Also no leeson, Cantoni group.

Nanyang Explosion Proof

Nanyang Explosion Protection Group Co. Ltd (hereafter indicated as CNE) locates in Nanyang city, Henan province, is one of the largest scientific research and production base of explosion-proof motors in China, the national export base for electro-mechanic products, and the national innovation enterprise as well as the chairman member of Ex motors branch of CEEIA.

Jiamusi Electric Machine Co., Ltd  YB2 explosion proof motor

JEM as the biggest Special motor factory in China was founded in 1937 in Shenyang city. In 1950 it was moved to Jiamusi city. In 2008, the company has established the management concept for modern enterprise and carried out the reformation in all aspects, thus forming a new style stock company. He manufactured the first Ex motor, crane and metallurgical motor axial-flow local fans and canned motor in the history of China.

Other local brand like Hengli, Pinxin, is also very famous supplier.