Chapter 4.1, Problem 13E

(a)

To determine

To explain: The technology to choose an SRS of 141 plots.

Answer to Problem 13E

The three phase starters the overload relay that gets connected with the three lines.

Explanation of Solution

Given information:

A ground survey visited a sample of 10% of these plots.”

USING TABLE D- The unique number between 1 and 1410 is considered.

From the table D the row is chosen. On taking the 4 digits, the number includes 1 and 1410. The corresponding plot is selected or move to the next 4 digits. The plot gets repeated for 141 values.

The line or wiring diagram is developed based on which the line get overload the relays for using three phase motor starters. The contact will be present at overload relays with the coil at control circuit. Hence, the coil and control circuit will be kept in contact.

In three wires system there arises low voltage protection. It gets connected to the controlling starter. Hence the starter is getting controlled. Due to the voltage failure the starter will get dropped out. Hence the voltage value will not pick automatically.

The overload relays are used in protecting the circuit from high current. They are connected with three phase starters in three lines.

Conclusion:

The three phase starters the overload relay that gets connected with the three lines.

(b)

To determine

To analyse: The first 3 plots.

Answer to Problem 13E

The plot 1387, 629 and 908 are selected.

Explanation of Solution

USING TABLE D

The seven unique number are selected between 1 and 1410

On starting from 122 as,

13873 81598 95062 90908 73592 75186 87136 95761

The number with a 7 between 1 and 1410 is considered and first 4 digits are taken. The plot is selected or else it can be moved to next 4 digit.

  $\begin{array}{l}1387\Rightarrow \text{select plot 1387}\\ \text{3815}\Rightarrow \text{Ignore}\\ \text{9895}\Rightarrow \text{Ignore}\\ \text{0629}\Rightarrow \text{Select plot 629}\\ \text{0908}\Rightarrow \text{Select plot 908}\end{array}$

Thus plot 1387, 629 and 908 are selected.

The T183 / T184 CALCULATOR is used with the following procedures as,

The followings commands are to be followed,

randInt(1,1410,3)

The first and second numbers are the bottom and upper margin. The values should lie between this.

The number of required selections includes the third number.

The MATH type is determined using randInt by PRB.

Conclusion:

The plot 1387, 629 and 908 are selected.