3 ICS3305 Classroom Excerise Process Var UNIT 4

School of Technology, Energy and Apprenticeship
Instrumentation Control & Electrical Technology (ICET)
ICS3305 – F2013

Classroom Exercise # 3 (Process variable Review)
PRESSURE CONVERSION TABLE mH2O mH2O psi inHg mmHg mbar
Pa

1
0.70307
0.34532
0.01359
0.01019
0.000102

psi
1.42233
1
0.49115
0.01934
0.0145
0.00015

What is the absolute pressure equivalent to 150 psi_g in psi_a?

inHg
2.8959
2.03602
1
0.03937
0.02953
0.000295

mmHg
73.55592
51.71493
25.4
1
0.75006
0.0075

mbar
98.0665
68.9476
33.8639
1.3332
1
0.01

Pa
9806.65
6894.757
3386.388
133.322
100
1

(Ans. 164.7 psi-a)

What is the vacuum pressure equivalent to 4.3 psia in psi vacuum?

(Ans. -10.4 psi_g)

What will be the pressure measured in psi at the bottom of a container filled with fluid with S.G. = 1.2 and fill 50% of 30 feet container?
(Ans. 7.8 psi)

What will be the height of fluid in feet’s with S.G. = 1.25 if the pressure at the bottom of the tank reads
78 psi
(Ans. 144 ft)

1

School of Technology, Energy and Apprenticeship
Instrumentation Control & Electrical Technology (ICET)
ICS3305 – F2013

Your proof:

Your proof:

Max.m Level = 11 ft

SGref = 1.2 (wet line)

14ft ft Min.m Level = 0

Your proof:

SG =
0.85

13 ft

3ft

2

School of Technology, Energy and Apprenticeship
Instrumentation Control & Electrical Technology (ICET)
ICS3305 – F2013

Show how you done it

Convert 77 oC into oF.__________________.

Convert 509 oR into K. ________________

Temperature Formulas
The need to convert from one temperature scale to another is a common everyday occurrence. The conversion factors are as follows:
To convert °F to °C  °C = (°F − 32)5/9
To convert °C to °F  °F = (°C × 9/5) + 32
To convert °F to °R  °R = °F + 459.6
To convert °C to K  K = °C + 273.15
To convert K to °R  °R = 1.8 × K
To convert °R to K  K = 0.555 × °R

What is the temperature at which the Fahrenheit and Celsius temperature scales read the same value? Show your proof?

From the adjacent Resistance vs temperature of RTD:
a-