Page 141 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

For precision resistors, 5 or 6 band are used. 5th band of 6 band resistor may be for fail rate
indication, in case of Military grade application. Refer manufactures catalogue for information.

TASK 2 : Identify the colour bands, and decode the resistance value of given resistance

1 Identify the value of resistors shown in Fig 1 from the colour bands and enter (Refer Task 1 Table 1).

Fig 1 Fig 2

2 Identify the first two colour bands of the resistors given by the instructor (in sequence commencing from the
1st colour band closer to one end of the resistor – Refer Fig 2.
3 Write the 1st number and 2nd number in Table 2.
4 Identify the colour of the 3rd band and write the multiplier value in the respective column in Table 2.
Table 2

Band Recorded Tolerance Max. Min. Measured Remarks
Sl. 1 st 2 3 4 resistance in Ohm value of value of value OK or not
value
resistance resistance
OK
th
rd
nd
No.
Band Band Band Band
%
1
2
3
4
5
6
7
8
9
10

TASK 3 : Calculate the tolerance value by the colour band
1 Compute the value of the resistor and record in (Refer Task 2 -Table 2).
2 Identify the 4th band colour and fill up the tolerance in (Refer Task 2 -Table 2).

124

CITS : Power - Electrician & Wireman - Exercise 60