Types of Direct Current (DC) Motors

Fundamental types of Direct Current (DC) motors:

1.) Series Field DC Motor - The series field DC motor contains field coils composed of a few turns of wire connected in series with the armature as shown in Figure 1 below.  This motor has high starting torque and a variable speed characteristic.  The greater the load the motor carries, the lower the speed.

Fundamental Overview of a DC Motor

Direct Current Motors - DC Motors are used to convert DC energy into mechanical energy. They are well suited for use as either constant-speed or adjustable speed motors. The three types (Shunt, Series, and Compound) which are available provide the range of speed torque characteristics for applications which require:

Warbling Alarm Circuit

The Warbling Alarm is made up of sawtooth wave generator and voltage controlled tone generator operated in tandem. Q1, R1, R2, C1, R3 comprise the sawtooth wave generator.

At the instant power is applied to the circuit, the voltage across C1 and hence at the anode of Q1 would be zero. C1 would then be slowly charged by R3 towards +12V. Once the voltage across C1 exceeds the value of the voltage appearing on the gate of Q1 as set by R1 and R2, the PUT (Programmable Unijunction Transistor) fires, that is, it will conduct, causing C1 to quickly discharge.Once C1 is discharged, Q1 will turn OFF, causing another charge - discharge cycle to be initiated. The manner in which the voltage across C1 varies, when plotted against time, resembles a sawtooth, hence the name sawtooth wave.

Inserting Alarm System to an Oil Pump Control Circuit

At some point in time, you may happen to have an old industrial pump unit wired inside an existing control panel that would require circuit modification in order to include an alarm system. What is being referred to here are pump systems most commonly found in industrial facilities such as oil pump, hydraulic pump, grease pump, water pump, air pump or air compressors, but nevertheless, the electrical circuit presented in this article may also be used to set an example to provide idea for other similar applications.

In heavy industrial facilities, one of the important foundation of a good working machinery is dependent on the condition of a well-oiled mechanism. This pertains to having a reliable lubrication system that ensures all moving parts of every machinery in the factory are well-lubricated in order to diminish friction and grinding on the machine's mechanical joints and contacts.

Electrical Circuit for Controlling a Lifting Electromagnet for Overhead Cranes with Top Running Trolley Hoist

When the need to conveniently pick up and lift heavy iron or steel objects for transferring from one place to another was seen as a necessity in heavy industrial facilities, the concept of using an electromagnet was implemented due to its ability to be turned ON and OFF which was then incorporated effectively to the hoist function of overhead cranes.

Overhead-travelling-crane magnets are electromagnetic device attached to the crane's hook to magnetically pick up heavy metallic loads for hoisting and transferring.  Cranes that are fitted with a lifting magnet are equipped with an electromagnet control circuit.