Chapter 11 - Instrument Calibration

Example 11.3.1 - page11-7

In [3]:
# percentage of the reading and percentage of full scale
#Given data :
a=10 #scale reading
b=70 # full scale
error1=-(0.5/10)*100  # in %
print "step 1"
print "error of reading ", error1, " %"
error2=-(0.5/100)*100 # in %
print "error of full scale is ", error2, " %"
print "step 2"
error3=(2.5/70)*100 # in %
print "error of reading is ", round(error3,2), " %"
error4=(2.5/100)*100 # in %
print "error of full scale is", error4, " %"

step 1
error of reading  -5.0  %
error of full scale is  -0.5  %
step 2
error of reading is  3.57  %
error of full scale is 2.5  %

Example 11.3.2 - page11-9

In [7]:
 # wattmeter error and correction figure
#Given data :
P1=120.0 # in W
V=114.0 #in volts
I=1 #in A
P=V*I 
error1=P-P1 # in W
print "correction figure is ", error1, " W"
error2=(error1/P1)*100  # in %
print "wattmeter error is ",error2," %"

correction figure is  -6.0  W
wattmeter error is  -5.0  %