Liquid Level Indicators: Technical Q&A & Selection Guide
Q: What is the primary advantage of using ultrasonic liquid level indicators over traditional methods?
A: The primary advantage is that they are non-invasive. Unlike mechanical floats or dipsticks, ultrasonic indicators do not require the tank to be opened or the process to be stopped. They measure through the container wall, maintaining the integrity of the vessel and preventing contamination of the liquid or exposure to hazardous chemicals.
Q: Where can I find these liquid level indicators?
A: These precision instruments are available through MUNRO. We offer a complete range of handheld and fixed ultrasonic solutions for industrial, laboratory, and marine applications.
1. Handheld Ultrasonic Liquid Level Indicator (Portalevel® ADVANCE / MAX)
Designed for: Fire safety cylinders (CO2, FM-200®, NOVEC™ 1230), Halons, and liquefied gases.
Q: What is the measurement accuracy of the handheld Portalevel® units?
A: These units are highly precise, capable of detecting liquid levels with an accuracy of ±1.5 mm (±1/16 inch) from the true liquid level.
Q: How long does it take to test a cylinder?
A: Testing is extremely fast. A single operator can typically inspect a cylinder in under 30 seconds, making it significantly faster than the traditional method of unhooking and weighing cylinders.
Q: Can it measure through painted or corroded cylinders?
A: Yes. The device includes adjustable gain (sensitivity) settings. For cylinders with heavy paint, rust, or pitting, the SPA (Sensor Power Amplification) feature (available on MAX/ADVANCE models) boosts the signal to penetrate difficult surfaces.
Q: What technical standards do these devices meet?
A: The Portalevel® series, specifically the MAX, carries major approvals including UL Listing, ABS (American Bureau of Shipping) Type Approval, and RINA acceptance, ensuring compliance with NFPA and ISO regulations.
2. Pipe Liquid Level Indicator (Portapipe®)
Designed for: Verifying liquid presence or levels in rigid pipes.
Q: What is the diameter range for pipes compatible with the Portapipe®?
A: The Portapipe® is effective on pipes ranging from 25 mm (1 inch) up to 330 mm (13 inches) in diameter.
Q: What are the two measurement modes available on the Portapipe®?
A:
- Time-of-Flight Mode: Used for horizontal pipes to calculate the exact level percentage based on the echo return time.
- Absence/Presence Mode: Used for vertical pipes to detect if liquid is present at a specific point (e.g., checking for fullness or blockages).
Q: What is the accuracy for pipe level measurements?
A: The device provides results within ±1% of the true level.
Q: Can it detect any liquid?
A: It works on most clean liquids (Water, Diesel, Petrol, etc.). The device comes pre-programmed with common fluid sound speeds, but users can also enter custom speeds of sound for unique fluids.
3. Ultrasonic Tank Liquid Level Indicator (Portatank®)
Designed for: Large industrial tanks, transformers, and bulk storage.
Q: What is the maximum tank size the Portatank® can measure?
A: The Portatank® is designed for much larger vessels than the handheld cylinder units. It allows for level detection in tanks with diameters from 0.5 meters up to 15+ meters.
Q: Does wall thickness affect the measurement?
A: The unit is powerful enough to measure through tank walls ranging from 0.5 mm to 20 mm thick. It works on various materials including steel, plastic, and glass.
Q: What is the "Oscilloscope" feature used for?
A: The Portatank® includes a handheld oscilloscope tablet. This allows the user to visually inspect the ultrasonic waveform returning from the tank. It is critical for advanced diagnostics, helping to differentiate between a true liquid echo and internal tank structures (like baffles or mixers) to ensure the reading is accurate (±10 mm).
4. Fixed-Level Monitoring Device (Permalevel® Single)
Designed for: Continuous, unmanned monitoring of critical cylinders.
Q: How does the Permalevel® Single differ from the handheld units?
A: While handheld units are for periodic inspection, the Permalevel® Single is a fixed system designed for 24/7 continuous monitoring. It is permanently attached to a cylinder to detect accidental discharge or slow seepage immediately.
Q: What outputs does the system provide for integration?
A: It offers a 4-20mA output and dry contact relays. This allows it to be integrated into a central Building Management System (BMS) or fire alarm panel, triggering a remote alert the moment a liquid level indicator drops below the set point.
Q: Is it suitable for limited access areas?
A: Yes. It is ideal for remote server rooms or high-security areas where daily manual checks are impractical.
5. Precision Liquid Level Indication in Marine Environments (Portalevel® MAX Marine)
Designed for: Shipboard fire suppression systems and offshore platforms.
Q: Why is a specific "Marine" version required?
A: Marine environments present unique challenges such as high humidity, salt corrosion, and vibration. The Portalevel® MAX Marine is built to withstand these conditions and carries the necessary IACS member classifications (like RINA and ABS) required for maritime safety audits.
Q: What is the IP rating of the marine unit?
A: The unit is enclosed in a robust, water-resistant housing rated to IP65, protecting it from water jets and dust ingress common in engine rooms and storage decks.
Q: Can it be used to convert level to weight?
A: Yes. When paired with the Portasteele® Calculator (often used alongside the MAX), the liquid level height can be mathematically converted into the agent weight (kg/lbs), which is the metric required for the formal Marine Fire Safety Certificate.
