Maker Pro
Maker Pro

Intrinsic Safety

B

BIGEYE

Can anyone point me to a website that demonstrates on how to select the
correct intrinsic safety barriers to suit instruments and cables (showing
cable calculations) for an intrinsically safe system design.
I have googled through many pages, but have been unable to find what I am
looking for.
TIA
 
S

SQLit

BIGEYE said:
Can anyone point me to a website that demonstrates on how to select the
correct intrinsic safety barriers to suit instruments and cables (showing
cable calculations) for an intrinsically safe system design.
I have googled through many pages, but have been unable to find what I am
looking for.
TIA

intrinsic safe is a huge galaxy. There are no general rules. There are only
specific requirements.
Intrinsic safe in a flammable gas atmosphere (hydrogen for example) would be
some what different than a flammable liquid situation (gasoline for
example).

Placement, voltages, current, are all considerations and apply.

Narrow your issue down to a county and maybe we can help
 
J

John B Smith

A useful reference book in UK is
Intrinsically Safe Instrumentation: a guide
by Robin Garside. 3rd Edition Revised 1997.
Covering this important protection concept in detail, this book explains the
key criteria including associated apparatus, system selection and design,
cabling, earthing, certification etc. The use of Simple Apparatus (which may
be installed without certification) is explained and the procedure for
assessing systems which do not have system certification is covered in
detail.
325 pages, extensively illustrated. A5 format
ISBN 0 9516848 1 7

Jaybetec
 
B

BIGEYE

SQLit said:
intrinsic safe is a huge galaxy. There are no general rules. There are
only
specific requirements.
Intrinsic safe in a flammable gas atmosphere (hydrogen for example) would
be
some what different than a flammable liquid situation (gasoline for
example).

Placement, voltages, current, are all considerations and apply.

Narrow your issue down to a county and maybe we can help


Country UK
Zone 1
Gas Classification IIC
Instrument Supply 24VDC
Loop Current 4-20mA

This is an academic exercise that I will need to do for college. Only need
to look at how we select IS barriers for a particular instrument,
considering supply voltage, current, etc.
Then need to select the correct cable, considering cable capacitance based
on conductor size/cable length, etc.
TIA
 
P

Paul E. Bennett

BIGEYE said:
[%X]

Country UK
Zone 1
Gas Classification IIC
Instrument Supply 24VDC
Loop Current 4-20mA

This is an academic exercise that I will need to do for college. Only need
to look at how we select IS barriers for a particular instrument,
considering supply voltage, current, etc.
Then need to select the correct cable, considering cable capacitance based
on conductor size/cable length, etc.
TIA

Take a look at:-

http://www.hse.gov.uk/comah/sragtech/techmeasureaclas.htm

I hope your college library can give you access to some of the EN500xx
standards referenced by this document as the finer details will be in those
documents (probably EN50020, 2002).

Other things that may be worth searching on are:-

DSEAR and ATEX.


--
********************************************************************
Paul E. Bennett ....................<email://[email protected]>
Forth based HIDECS Consultancy .....<http://www.amleth.demon.co.uk/>
Mob: +44 (0)7811-639972
Tel: +44 (0)1235-811095
Going Forth Safely ....EBA. http://www.electric-boat-association.org.uk/
********************************************************************
 
B

BIGEYE

Paul E. Bennett said:
BIGEYE said:
SQLit said:
Can anyone point me to a website that demonstrates on how to select the
correct intrinsic safety barriers to suit instruments and cables
(showing cable calculations) for an intrinsically safe system design.
I have googled through many pages, but have been unable to find what I
am looking for.
TIA
[%X]

Country UK
Zone 1
Gas Classification IIC
Instrument Supply 24VDC
Loop Current 4-20mA

This is an academic exercise that I will need to do for college. Only
need
to look at how we select IS barriers for a particular instrument,
considering supply voltage, current, etc.
Then need to select the correct cable, considering cable capacitance
based
on conductor size/cable length, etc.
TIA

Take a look at:-

http://www.hse.gov.uk/comah/sragtech/techmeasureaclas.htm

I hope your college library can give you access to some of the EN500xx
standards referenced by this document as the finer details will be in
those
documents (probably EN50020, 2002).

Other things that may be worth searching on are:-

DSEAR and ATEX.


--
********************************************************************
Paul E. Bennett ....................<email://[email protected]>
Forth based HIDECS Consultancy .....<http://www.amleth.demon.co.uk/>
Mob: +44 (0)7811-639972
Tel: +44 (0)1235-811095
Going Forth Safely ....EBA. http://www.electric-boat-association.org.uk/
********************************************************************


404 error
 
S

Steve Y

Whilst Robin's book is OK, there are also free application notes
available from http://www.mtl-inst.com/mtlsupport.nsf

Don't forget that when choosing a barrier for an application, you need
to find a barrier/instrument combination that is safe but one that works
in the way you want it to as well.

Steve
 
Top