Choose the right VCI capsule – complete guide for cabinets and panels
VCI capsules do not remove moisture. They emit an anti-corrosion gas. That is an important distinction – and it is the reason we call them emitters, not desiccants.
When the temperature is above freezing, VCI evaporates from the capsule. The vapor gradually fills the entire cabinet and forms an inert atmosphere where metals do not corrode. This condition is reached after a few hours, depending on temperature conditions.
There is a slight positive pressure from the evaporation that fills the cabinet. The pressure is enough to fill a specific volume, but not enough to be physically noticeable. Once the cabinet is filled, all metal surfaces are protected – including those that are impossible to reach with coating or grease.
How to place the VCI capsule correctly
The gas spreads by diffusion from a solid. Imagine a beach ball of protective atmosphere forming around the capsule. The parts you want to protect should be located inside the beach ball. The size of the beach ball is what we use to determine which capsule is suitable for which cabinet.
If you have a long or large cabinet, think of it as stacking multiple balls inside the cabinet. Place one capsule as close to the center of each volume as possible. This ensures even coverage throughout the entire cabinet.
Which VCI capsule fits my cabinet?
Zerust covers everything from 4 liters to 24,000 liters. Choose a capsule based on two factors: cabinet volume and desired protection time.
- Transmitters, junction boxes, and switches: Use 3/4" Plastabs. No larger than a thick postage stamp, but covers up to 6 liters for 2 years. Features double-sided tape as standard.
- Small electrical cabinets: Use VC 1-1. Covers 120 liters for 1 year, or 60 liters for 2 years.
- Rittal racks and large panels (up to 1 m³): Use VC 2-1 (1 year) or VC 2-2 (2 years). Both cover 1000 liters – but feel free to use 2 capsules separated from each other in accordance with the beach ball theory.
- Large switchgear and rooms: Use multiple VC 2-1/VC 2-2 units, or the powerful VC 6-2 which covers 25 m³ for 2 years.
It is impossible to over-protect. Insert as many as you like.
How to read the capsule name
All information is contained in the product designation. VC2-1 means: diffusion radius 2 feet (2 × 0.3 m = 0.6 m), and protection time 1 year. The beach ball therefore has a radius of 0.6 m.
Can you combine VCI capsules with silica gel?
Yes. VCI and desiccant work independently of each other and do not interfere with each other's function. In humid environments – offshore, coastal installations, process industry – this combination is common practice. Read more about combining VCI and silica gel here.
Frequently asked questions about VCI capsules
How long does a VCI capsule last?: Depends on the model – from 1 to 2 years. VC 2-2 covers 1 m³ for 2 years. VC 6-2 covers 24 m³ for 2 years.
What if the cabinet is larger than one capsule covers?: Use multiple capsules. Place them so that the volume is covered by separate "protective balls".
Does VCI work on aluminum and stainless steel?: Yes. Zerust VCI protects all common metals – steel, aluminum, copper, and brass. VCI is also an approved method under NORSOK Z-006 for the preservation of instrumentation and electrical components.
Do I need to clean the cabinet first?: Wipe off moisture and dirt. VCI prevents new corrosion, but does not remove existing rust.
What happens if the expiration date has passed?: Replace the capsule immediately. An expired capsule provides no protection.
Download free info poster
To make choosing a capsule easy, we have created a 70×25 cm info poster with an overview of all capsules and volumes. You can receive it for free with your first order, or download it here:
Unsure which capsule you need? Call us at 51 94 47 00 or send an email to post@realmarine.no – and we will find the right solution for your facility.
