Permalevel® FEATHERWEIGHT Gas Weight Constant Monitoring of Fixed Fire Suppression Systems is the world’s first such system with 3 gas-group capability.

Gas Weight Constant Monitoring System
P/N: 2594650-PMLFW

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Brand new technology released March 2021

World’s first dedicated three-gas system to continually monitor loss of agent quantity due to leakage in high-pressure seamless CO2 cylinders, liquefied clean agents (NOVEC™1230, FM-200® with Nitrogen) and non-liquefied clean agents (Inert gases e.g.Inergen™).

Have 100% visibility on your highly pressurised cylinders, 24/7 365 days a year, with real-time diagnostics. Link your cylinders with your fire alarm system and receive instant notifications of critical leakages.

Improve Your Fire Safety

Permalevel FEATHERWEIGHT benefits Permalevel FEATHERWEIGHT USPs

Permalevel® FEATHERWEIGHT electronics enable multi-relay power and communications up to 4 electronic units, each controlling 12-cylinders, totalling 48-cylinder monitoring capability from 1 power source.

Permalevel® FEATHERWEIGHT is designed for total flood fire suppression systems in seamless cylinders

Coltraco brings you the innovative answer to the question of monitoring fire systems.

Merging fundamental mathematics with cutting edge engineering, to continuously monitor the mass of your cylinder contents. This is a critical way of measuring agent loss and is the only method that is not affected by pressure or temperature. We bring you this intuitive, simple to use, and very light constant monitoring system, weighing merely 700g. 

3-gas Solution: CO2, Clean Agents, Inert

Choose Permalevel® FEATHERWEIGHT for CO2, liquefied and non-liquefied clean agents.

For non-liquefied clean agents where pressure is used as a direct indication of agent quantity, our system converts the cylinder’s fill pressure to agent mass.

The user does not have to worry about temperature fluctuations during maintenance schedules. This is because agent mass is independent of temperature, with the ability to set pressure-equivalent leak alarm thresholds, allowing you to adhere to ISO and NFPA regulatory requirements more easily. For more information on our services, you can check out customer support here.

Permalevel Featherweight cylinder details screen Permalevel Featherweight status screen

What are the Key Benefits?

  • Better Accuracy – within 1% of true agent weight and within 1% for pressure loss in Inergen™ systems above 10kg agent weight.
  • Lighter, Cheaper – much lighter than traditional full-mechanical load weigh systems
  • Easy Installation – easily configurable to retrofitting along with full refits of your fire suppression systems
  • Operates at High Temperatures
  • Integrated Power – power 4 units from 1 source – connecting 48 cylinders, and reducing wire congestion.
  • No Maintenance Disruption – with our new in-built sensor release system, you no longer need to shut down your entire system

We Designed this System as an Intelligent and Highly Accurate Constant Monitoring System Rather than a Conventional Load Weigh Monitoring System.

  • It is intended as a constant and integrated control system able to constantly monitor & detect both minute and major fluctuations in agent fills
  • In seamless cylinders containing highly pressurised liquefied and non-liquefied gaseous extinguishing agents,
  • From CO2 to Inergen, from NOVEC™1230 to FM200™.


High-Pressure cylinders are, in general, more susceptible to leakage than low-pressure systems. Increasing the design pressure of a cylinder or an increase due to a temperature rise will actually increase the chance of leakage; typically through one of the weak points – such as the valves and pressure gauges. Therefore, it is vital that high-pressure cylinders are monitored for contents loss, and it is reasonable to suggest that as the pressure increases, so does the importance of monitoring them. This is why the major fire OEM’s are themselves constantly monitoring their own gaseous systems whether with float gauges or valves that monitor the pressure. But neither of these methods can be retrofitted, and they still require external means to ensure that they are working. This is why the Permalevel Featherweight was designed. It combines the ease of retrofitting with the highest accuracy of constant monitoring, capable of detecting incremental and major contents loss of both liquefied and non-liquefied systems

  • The Permalevel Featherweight will measure and monitor the agent weight of any high-pressure seamless cylinders with suitable mounting points – including HFC.
  • The contents of the seamless cylinder can be liquefied or non-liquefied.
  • The principle behind the system is weight measurement, based on the incredibly accurate S-type load cell.

Installation Criteria

The seamless cylinder needs to have a neck thread so we can secure the neck ring. The hose connections ideally need to be flexible; if the hose connection is solid, then a small modification on the fire system hose may be needed so we can install the Permalevel Featherweight. If the hose connection is flexible, then it will operate perfectly.

Go Above and Beyond Regulations:

  • For liquefied systems, regulatory standards require checking for the agent weight every 6 months to ensure it does not drop below 10% for CO2 or 5% for clean agents and HFC systems. The Permalevel Featherweight is perfect for this because it offers 24/7 monitoring of the agent weight.
  • For non-liquefied systems (such as Inergen systems), regulatory standards require the cylinder pressure to be checked every 6 months to ensure the pressure does not drop below 5%. However, since the pressure is a direct indication of agent quantity, monitoring weight loss can indicate the equivalent pressure loss with 1% accuracy or better.


  • The Permalevel Featherweight’s software will convert agent weight, or agent loss, into the equivalent pressure loss allowing you to comply with the pressure regulatory requirements. The software will calculate the equivalent agent weight based on the pressure of the cylinder, and once this calculation is made, the Permalevel Featherweight will continuously monitor the agent weight that is related to the pressure. As soon as the pressure drops, the agent weight will also drop, and the operator will immediately be notified.
  • The benefit of this method is that it is not temperature dependent. Yes, pressure changes when temperature changes but once pressure is converted to agent weight, the weight will not be affected at all by temperature. So, there is no need for temperature compensation, which often goes missed during inspections. During an inspection, technicians usually read the pressure from the pressure gauge without checking the temperature and most pressure gauges are only accurate to around 2.5%, whereas the Permalevel Featherweight is accurate to 1% for agent weights less than 10kg or even higher accuracy for agent weights above 10kg.

Comparison with Conventional Load Weigh Systems

  • These systems may appear to share a concept, but I assure you they are very different.
  • They both monitor agent weight to some extent and alert a user when a leak has occurred. However, the level of information – the actionable information is very different.
  • Rudimentary load weigh systems are onlya “leak” or “no-leak” alert system. They indicate with the position of a counterweight arm if an agent leak threshold has been surpassed.
  • However, the severity of the leak is unknown. Cylinders could have leaked by 11% or 50%, yet provide no detailed no information and are, therefore, unequipped with the knowledge needed to guide the level of response.
  • A severe leak that dramatically exceeds the threshold is far more of a critical situation that requires a very different response.
  • Load weigh systems provide very little to no information,
  • whereas the Featherweight is opening up the constant monitoring market to a level not seen before.
  • Never have we been able to understand in such detail the minute-by-minute condition of our cylinders – information that allows us to react in real-time and avoid disaster.

NUMBER OF COMPONENTS: Standard kit ~16 (1 x neck ring, 2x studding bars, 2x bolts, 2x locking plates, 8x hex nuts, 2x connector nuts)


Self-extinguishing Blend PC/ABS

Operating Voltage


Frequency Range


Operating Temperature

-20C ~ +50C

Operating Humidity

20 ~ 90% RH non-considering


4.3 inch TFT/Transmissive, no module

Number of cylinders


Power Relay Potential


Mounting Options

DIN (EN 60715) rail


100 grams (1% or less of agent weight above 10kg)

Connectivity Options

Monitored Input (for external fire panel integration) on the communications model.


700 grams


213 x 89 x 53.3 mm (L x H x W)


115 ~ 264VAC 120 ~ 370VDC

IP Rating

IP 54 Max

Kitting Weight

3.2-3.6 kg (including load cell)

Standard Collar Internal Thread

W80x1/11 grade, Internal Diameter: 78 mm
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    How to monitor fire systems?

    Constantly monitor cylinders 24/7 to ensure they are at designed capacity. We also provide real-time information on the exact amount of agent in your cylinder.

    How do you see the results?

    Immediate notice of leakage on a full-colour 4.3” display. The system will show the exact amount of agent loss, including percentage loss with 100-gram accuracy.

    How to comply with fire safety regulations?

    Pre-programmed thresholds based on regulatory needs: 10% for CO2 and 5% for Clean Agents, for Inergen™, you will also be given the pressure loss which is intrinsically linked to mass.