Let’s start with a simple question: What’s protecting your electrical infrastructure, the lifeblood of your facility?
In the industrial world, it’s not just about keeping things running. It’s about keeping people safe, maintaining uptime, and extending the life of your equipment. And one of the simplest ways to do all of that? Choosing the right electrical enclosures.
Whether you’re housing a single control panel or managing a complex system of drives, sensors, and PLCs, your enclosures are doing the quiet work of shielding your assets from heat, dust, water, impact, and more. But choosing the wrong one–or cutting corners on quality–can lead to costly downtime and unnecessary risk.
At HESCO, we’ve spent decades helping manufacturers across the Northeast get this decision right. And we’ve partnered with nVent Hoffman for more than 60 years because we believe in putting the best in front of our customers. In this guide, we’ll walk you through everything you need to know about electrical enclosures, how NEMA ratings work, and which providers are delivering the most value today.
Source: HESCO
What Is an Electrical Enclosure?
Electrical enclosures are physical housings, typically made from metal, plastic, or fiberglass, that protect electrical components from environmental threats. These threats can include:
- Dust and debris
- Water or moisture
- Temperature extremes
- Unauthorized access
- Chemical exposure
The goal is simple: to keep your people safe and your automation systems running. The design and material of the enclosure depend on where it will be installed (indoor vs. outdoor), what it’s protecting, and what environmental hazards are present.
For example, an enclosure in a clean, climate-controlled panel shop has very different requirements than one mounted on a dusty sawmill production floor or exposed to salt air at a coastal plant.
And while enclosures might look like just another box on the wall, their construction, seal integrity, and certification standards are critical to long-term reliability. When a drive goes down due to dust contamination or moisture ingress, the resulting downtime can be far more costly than investing in the right enclosure upfront.
Understanding NEMA Ratings
In the U.S., electrical enclosures are typically rated by NEMA (National Electrical Manufacturers Association). These ratings categorize how much protection an enclosure offers against specific hazards.
Here are a few common ones:
NEMA 1
- Use: Indoor only
- Protection: Basic protection against contact and falling dirt
- Example: Office A/V equipment, general-purpose control panels
NEMA 2
- Use: Indoor
- Protection: Adds light drip/water resistance
- Example: Panels in clean facilities with low humidity
NEMA 3 / 3R / 3S
- Use: Indoor or outdoor
- Protection: Protection from windblown dust, rain, sleet, and snow
- Example: Generator skids, outdoor junction boxes
NEMA 4 / 4X
- Use: Indoor/outdoor
- Protection: Water-tight; 4X adds corrosion resistance
- Example: Food & beverage, chemical, marine environments
NEMA 12
- Use: Indoor
- Protection: Dust, dripping liquids, and light oil/coolant splashes
- Example: Shop floors with particulate contamination
Each facility should assess environmental conditions to select the right NEMA-rated enclosure. Going overboard can mean unnecessary cost; underestimating your environment can mean system failure.
Source: Automation Ready Panels
Real-World Example: Dusty Facility, Simple Solution
Let’s say you manage a woodworking facility. Between sawdust, airborne particles, and fluctuating temperatures, your control systems need serious protection. The solution? Wall-mounted NEMA 1 or NEMA 12 enclosures that shield sensitive drives and PLCs from contaminants.
Without these enclosures, you’re looking at fried circuits, unexpected downtime, and some potentially expensive repairs. With them? Smooth operation and one less thing to worry about.
But it’s not just about installation; it’s also about maintainability. The right enclosure makes ongoing service and visual inspections easier, which directly affects how quickly you can spot potential issues before they snowball into shutdowns.
The 3 Best Enclosure Providers on the Market Today (In Our Opinion)
If you’re exploring your options, here are three enclosure manufacturers consistently leading the way in quality, innovation, and value:
1. nVent Hoffman
As one of the most recognized names in the industry, nVent Hoffman has been building durable, high-performance enclosures for over 75 years. Known for their broad product line, excellent availability, and reliable NEMA compliance, Hoffman offers enclosures for:
- General-purpose indoor control panels (NEMA 1, 12)
- Outdoor environments (NEMA 3, 4, 4X)
- Harsh industrial and corrosive settings (stainless steel, NEMA 4X)
Their panel shop automation tools and customization options are also a major plus, especially for OEMs and system integrators.
Why HESCO partners with them: We trust the consistency, and we’ve seen the longevity of these enclosures in real-world conditions across thousands of installs.
2. Saginaw Control and Engineering
Saginaw is another American manufacturer with a long track record. They offer off-the-shelf and custom solutions and are known for their quick turnarounds.
Specialties include:
- NEMA 1, 3R, 4, 4X, and 12 enclosures
- Custom sizes and configurations
- Precision fabrication for OEM applications
They’re particularly strong in scenarios where a tailored fit is important, and their catalog of enclosure accessories, like back panels and mounting options, makes integration easier.
3. Rittal
If innovation is what you’re after, Rittal brings a global edge. Their enclosures are often engineered for high-efficiency, modular builds that support faster installation and maintenance.
Key highlights:
- Rugged, scalable designs
- Integrated cooling and climate control systems
- Online Enclosure Selector Tool to help you configure your ideal solution
Rittal is a strong fit for high-tech applications, including data centers, energy systems, and modular automation platforms.
How to Choose the Right Enclosure for Your Facility
Not sure which brand or NEMA rating is right for your space? Here’s a quick checklist to guide your selection:
- Assess the environment. Is it clean or dusty? Is water present (e.g., washdown, condensation)? Will the enclosure be used indoors or outdoors?
- Evaluate what you're protecting. Sensitive controls like PLCs or HMIs may require higher NEMA ratings. Motors or less complex hardware may be fine with basic protection.
- Think about lifecycle and support. Are replacement parts and accessories easily available? Will the manufacturer provide guidance on maintenance best practices? Does your team know how to inspect or service this type of enclosure?
- Consider future scalability. Are you expecting to add more equipment next year? Will you need modularity or integrated cooling down the line?
Final Thoughts: Enclosures as a Strategic Investment
Electrical enclosures may not be the most talked-about component on your plant floor, but they play one of the most important roles. They guard your investments, reduce your downtime risks, and support your facility’s long-term performance.
At HESCO, we help manufacturers across New England and the Mid-Atlantic make smart, future-proof decisions about their automation infrastructure. If you’re selecting enclosures for a new build, planning a retrofit, or just want to make sure your existing ones are up to code, let’s talk.
