Hawkins Electrical Guide v. 03 (of 10) Questions, Answers, & Illustrations, A progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications

The practical electrician frequently has to make tests of various kinds which require the rapid and accurate measurement of voltage, current and resistance. It is therefore esse...

If a compass needle be allowed to come to rest in its natural position, and a current of electricity be passed through a wire just over it from north to south, the north seeking...

An ammeter or ampere meter is simply a commercial form of galvanometer so constructed that the deflection of the needle indicates directly the strength of current _in amperes_....

For satisfactory operation, the brushes and commutator must be kept in good condition. To this end the main thing to be guarded against is the production of sparks at the brushe...

Before Starting a Dynamo or Motor.--When the machine has been securely fixed, it should be carefully examined to see that all parts are in good order. The examination should be...

Series and Parallel Connections.--When it is necessary to generate a large and variable amount of electrical energy, as must be done in central generating stations, apart from t...

In operating motors of any considerable size, whether connected to the public supply mains of a central generating station for combined lighting and power service, or to power s...

This trouble is of frequent occurrence in both old and new machines. If a dynamo fail to excite, the operator should first see that the brushes are in the proper position and ma...

NOTE 1.--It is always advisable, in case of trouble, to make sure that the fields of the motor are magnetized. This test is easily made by first closing the main knife switch, t...

The excessive heating of the parts of dynamos and motors is probably the most frequent and annoying fault which arises in operation. When the machine heats, it is a common mista...

Short Circuit in Individual Coils.--This is a common fault, which makes its presence known by a violent heating of the armature, flashing at the commutator, flickering of the li...

A large proportion of the mishaps and breakdowns which occur with dynamos and motors arise from causes more strictly within the province of the man in charge than in that of the...