Technical Comparision of Process Parameter Measurement Devices
S.N. Description Mechanical Switches TransmitterAnalog TransmitterSmart TransmitterProfibus
6 Calibration Drift
over a period of
time
More and
hence requires
frequent
calibration
check
More and
hence requires
frequent
calibration
check
Very Less drift
& high stability
Very Less
drift & high
stability
7 DCS interface
Engineering
Aspect
Very easy and
involves no
high skill ness
Very easy and
involves no
high skill ness
Easy Slightly
complicated
and requires
high skill ness
& Time
8 Erection &
Commissioning
Aspect Time
Requires more
time
Requires more
time
Requires more
time
Requires less
time
9 Market
Availability
Many Vendors
in market
Many Vendors
in market
Less number of
vendors
Only selected
vendors in
market
10 Delivery 4 to 6 weeks 6 to 8 weeks 6 to 8 weeks 8 to 10 weeks
7.3 Executive Summary:
The cost benefit analysis is of analogue transmitters, smart transmitters, profibus
transmitter and pressure switches is given here under for ready reference:
Typical Cost Benefit Analysis
Application
of Transmitter
Qty
Analog
Transmitter
(Fixed range)
Smart Transmitter
(4-20mA, HART)
Smart Profibus
Transmitter
Pressure/DP
Switches (@
Unit rate of Rs.
5000/-)
Nos. U/R Total U/R Total U/R Total Qty. Total
DP transmitters
for Bag Filters
26 10000 260000 28000 728000 35000 910000 26 130000
Pressure
Transmitters for
Bag Filters
26 8000 208000 23000 598000 30000 780000 26 130000
RABH DP
Transmitters-
DP type
17 10000 170000 28000 476000 35000 595000 17 85000
RABH Pressure
Transmitters
1 8000 8000 23000 23000 30000 30000 0 0
Coal Mill
Bag Filter
Transmitter-DP
Type
5 10000 50000 28000 140000 35000 175000 5 25000