|
The cargo tank high & hihg-high level alarm and temperature monitoring system is throughly designed according to IMO'S latest requirements, and are to be required by IBC code
◈ Operating Principle
The high & high-high level switch with temperature sensor is available for simultaneous detection of cargo temperature with high & high level detection, but is electrically independent each other. When the magnetic float moves upward with rising level, the hermetically sealed magnetic reed switch within the stem will be de-activated. This switch will be in an open-state position, which output alarm.
When the magnetic float moves downward with falling level, the reed switch will be activated and will be in a closed-state position (non alarm position).
The 95% switch is normally for alarm, and the 98% switch is normally for either closing of valves or give a visual and audible tank overfill alarm for shut-down of pumps. A float test lever is provided for manually functional test to check integrity of high and high-high level alarm system.
The temperature monitoring system conisists of temperature sensor current signal converter and display unit with high/low tenperature alarm.
Three, two or one pieces of temperature sensors will be inserted in guide pipe. In case of three pieces of temperature are required, each of them will be located about 1m below deckhead, middle of tank depth and about 1meter above tank bottom respectively. In case of two, usually mid-tank and bottom, and at bottom in case of one.
If the gauging of vapor pressure isn additionally required, the sensor of vapor prssure finding is usually fitted under the fitting flange of terminal box to detect the pressure of vapor from fluid in tank.
The vapor pressure alarm monitoring system can be optionally provided in addition to this system for the ship which is to be built under VECS requirements of USCG regulation.
◈ Features
• Simultaneous measurement of level alarm and high temperature alarm by one unit.
• Most advanced electric technology for high reliability and durability.
• Certified by major certifying authorities.
• Designed for all kind of liquid.
• Simple construction.
• Intrinsically safe designed unit is applicable to all kind of inflammable fluids.
◈ Technical Specification
• Detection unit
※ Level Alarm-Reed switch with magnetic float
※ Temperature Sensor-PT-100Ω or two-terminal IC
• Temp. Indicator: By selected type-LCD indicator
Range-0~100℃(3-digit)
• Material : ※ Housing-SUS304
※ Flange-SUS304 or SUS316
※ Guide pipe-SUS304 or SUS316L
※ Float-SUS316L
• Detecting Accuracy : Alarm-±2mm
Temperature-±1℃
• Anti-Explosion Structure : Intrinsically safe
EEX ia ∥C T4
• Protection : IP56 over
• Max. working pressure : 5㎏/㎠(option 20㎏/㎠)
• Temp. measuring range : -50~+120℃
• Contact rating : 250VAC, 0.25A
• Specific gravity : 0.65~1.5
• Installation : ※ Level sensor-JIS 5K 100A(STD.)
※ Level & Temp. sensor-JIS 5K 100A(STD.)
• Conduti connection size : JIS 5K32A FF(standard)
• Power supply : AC110/220V, 60Hz(Back up : DC24V)
• External alarm : High and high-high alarm(overfill)on the bridge top
• Alarm point : ※ High alarm-at 95% of volume
※ High-high alarm-at 98% of volume
• Cargo monitoring panel :
The cargo monitoring panel will be designed and arranged for level alarm, high temp.
alarm and temp. measurement based on the number of tank location etc.
The cargo monitoring panel gives audible and visible alarm as well as cargo temp.
indication on the monitoring panel and also external alarm prepared by control panel
gives an audible and visible notification to the operators on deck.
|
