The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
Practical Electricity And House Wiring
The only catch is that the pump must be running when there is a fire. What if the fire was caused by a defect in the wiring system? Maybe the fuses blew as the fire was being started; the pump won't be running. The remedy is to consider the farm water system as a fire pump, and wire it accordingly. The Code in Section 2321a permits a fire pump to have its own service. Wire the pump in ahead of all other fuses, ahead of all switches, right after the meter (naturally through a switch and fuses for the pump and nothing but the pump). Use underground wires so that nothing will put the pump out of commission. And treat the pump as the most important piece of equipment on the farm—service it an treat it well.
Plan for Future Years.—It is monotonous to repeat any story, but this story is too important to be overlooked. Very few farmers when first wiring their farms, have the slightest idea about the total amount of electrical power they will be using one or two or five years after the farm is wired. Few will realize the type of installation they will need in future years, the size of wires and amperage of switches that will be needed to take care of tomoi-row's loads. In all your work, estimate generously for the future, especially for feeders between buildings, then increase the wire by another size or two to be really on the safe side. That may result in what looks like a high cost today, but will save money tomorrow.
Motor Characteristics; Motor Wiring
Electric motors today are used very extensively, for their first cost is low, they consume electricity only in proportion to the amount of work they are called upon to deliver, and with reasonable care have extremely long life. Their operating cost is very low. Unlike gasoline engines, they have large overload capacities, which explains why a 3-Hp. electric motor frequently will replace a 5-Hp. or larger gasoline engine with complete satisfaction.
There are many different types of motors, some of which will be described below, but before considering the different types, let us investigate the characteristics of motors in general.
Torque.—Most types of motors have large overload capacity. A motor which is designed to deliver 1 Hp. continuously, will usually deliver up to 3 Hp. while it is starting; it is then said to have "300% starting torque." The same motor while running will instantly if called upon, deliver up to 21/2 Hp. for short periods of time (for example, if a motor is used on a wood saw, 1 Hp. may be sufficient until a knot in the wood is fed to the saw when 21/2 Hp. may be required) ; the motor is then said to have "250% pull-out torque."
