FULTON VSRT-60 - Page 114

APPENDIX - A
Fulton Ltd
TI-149-High Integrity Water Limiters-2017-2
Pros
Cons
GWR
• Works with RO and DeMin Water
• SIL2 low water limiter function
• Doesn’t mistake foam for water
level Provides an analogue
signal
• Doesn’t attract scale
• Function not affected by low level
scale or debris build-up.
• Probe lengths need to be ordered to
size within a range
VF
• Works with RO and DeMin Water
• SIL2 low water limiter function
• Doesn’t mistake foam for water level
• Probe lengths need to be ordered to
size (can’t be cut to length)
Conductive
• Probes can be cut to length
• SIL2 low water limiter function
• Detects water tracking across insulation
• Mistakes foam for water level.
• Function affected by low level scale
or debris build-up.
GWR & VF
• Two separate technologies to reduce
probability of undetected double
failure.
• SIL3 low water limiter function
2 x
Conductive
• SIL3 low water limiter function
• Two probes of the same technology
increase the probability of
undetected double failure.
Glossary of terms:
SIL2:
Safet
y Integrity Level 2 – Applied to a system or part of a system to indicate that the Probability of Failure on
Demand (PFD) is in the region 10
-2
to 10
-3
.
SIL3:
Safet
y Integrity Level 3 – Applied to a system or part of a system to indicate that the Probability of Failure on
Demand (PFD) is in the region 10
-3
to 10
-4
.
PFD:
Probabi
lity of Failure on Demand. The likelihood that a safety device or system will fail if the system needs to act
to prevent a dangerous occurrence.
GWR:
Gui
ded Wave Radar level measuring and limiting probe device.
VF:
Vibr
ating Fork Level limiting probe device
Limiting device:
A devi
ce that stops a machine if the machine enters an unsafe state or if the limiting device detects a fault with
itself.
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Every effort is made to ensure accuracy at time of going to press. However as part of our policy of continual product improvement, we reserve the right to alter specifications without prior notice.
Fulton Ltd Tel: +44 (0)117 972 3322
5 Fernhurst Road, Fishponds, Fax: +44 (0)117 972 3358
Bristol, BS5 7FG Email: sales@fulton.co.uk
England Website: www.fulton.co.uk
VSRT-IOMM-2019-1
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