Low Voltage vs. Medium Voltage Switchgear: Which One Does Your Project Need?

One of the most common questions we hear from project engineers and facility managers is: "Should I use low voltage or medium voltage switchgear for my project?"

It's a critical question. Choosing the wrong voltage class can lead to oversized equipment, wasted budget, unnecessary complexity — or worse, undersized equipment that can't handle your load safely.

In this article, we'll break down the differences between low voltage and medium voltage switchgear, explain where each type is used, and give you a decision framework you can apply to your own project.

The Simple Difference: Voltage Level

But voltage level is just the starting point. The real question is: what does your project actually need?

When to Use Medium Voltage (MV) Switchgear

Medium voltage switchgear handles the "backbone" of your power distribution system. You'll need MV switchgear when:

1. Your Facility Receives Power at Medium Voltage

Many industrial plants and large commercial buildings receive their utility supply at 10 kV or 12 kV. MV switchgear is required to receive, distribute, and protect this incoming power before it reaches transformers.

2. You Have Large Motors or Heavy Loads

Industrial motors above 200-300 kW are often driven at medium voltage for efficiency. MV switchgear provides the control and protection these motors need.

3. You're Building or Connecting to a Substation

Whether it's a new substation or an extension to an existing one, MV switchgear is essential for connecting transformers, feeders, and protection relays.

Common MV Products:

• KYN28-12 — Indoor metal-clad withdrawable switchgear (12 kV)

• XGN15-12 SF6 RMU — Gas-insulated ring main unit for secondary distribution

• KYN28-24 — 24 kV version for higher voltage networks

When to Use Low Voltage (LV) Switchgear

Low voltage switchgear handles the "last mile" — distributing power from transformers to your actual equipment, lights, HVAC, and machinery.

You'll need LV switchgear when:

1. Distributing Power Within a Building or Facility

After the transformer steps down from MV to 400 V, LV switchgear takes over. It distributes power to individual floors, departments, or production lines.

2. You Need Motor Control Centers (MCC)

LV withdrawable switchgear like MNS or GCS serves as an MCC, providing individual motor starters, VFD panels, and protection circuits.

3. You're Setting Up a Data Center

Data centers rely heavily on LV switchgear for UPS distribution, PDU feeds, and backup power systems — with the need for high reliability and easy maintenance.

4. Commercial Buildings and Infrastructure

Shopping malls, hospitals, airports, and hotels all use LV switchgear for lighting, HVAC, elevators, and emergency power distribution.

Common LV Products:

• MNS / GCS / GCK — Withdrawable switchgear for complex, maintenance-intensive applications

• GGD — Fixed switchgear for cost-effective, simpler installations

• ATS Distribution Box — Automatic transfer switch for dual power supply systems

• DFW Cable Distribution Box — Flexible cable branching for utility networks

The Decision Framework: 5 Questions to Ask Yourself

Question 1: What voltage does my utility supply?

• 10-12 kV → You need MV switchgear at the intake, then LV switchgear after the transformer

• 380-400 V → You only need LV switchgear

Question 2: What is my total electrical load?

• Above 2,000 kVA → Consider a hybrid MV+LV system

• Below 2,000 kVA → LV switchgear is usually sufficient

Question 3: How critical is uptime?

• Mission-critical (data centers, hospitals) → Withdrawable LV switchgear for hot-swappable maintenance

• Standard industrial → Fixed LV switchgear (GGD) may be adequate

Question 4: Do I have large motors?

• Motors > 200 kW → MV motor control may be more efficient

• Motors < 200 kW → LV switchgear handles these easily

Question 5: What are my expansion plans?

• Planning to scale → Choose withdrawable designs that allow easy addition of circuits

• Fixed requirements → Fixed designs are more cost-effective

Why Tuoxin Electric Can Supply Both

One of Tuoxin Electric's key advantages is that we manufacture both MV and LV switchgear under one roof:

• MV Products: KYN28-12, KYN28-24, XGN15-12 RMU, XGN-24 RMU

• LV Products: MNS, GCS, GCK, GGD, XL, ATS, DFW, PZ30

• Complete Solutions: Prefabricated substations, busway systems, cable trays

This means you can source your entire switchgear package from a single manufacturer — ensuring compatibility, consistent quality, simplified procurement, and better project coordination.

Conclusion: It's Not About "Better" — It's About "Right"

Low voltage and medium voltage switchgear aren't competitors — they're teammates in a complete power distribution system. The key is understanding where each type fits and selecting products that match your specific voltage requirements, load characteristics, and operational needs.

Not sure which configuration is right for your project? Our engineering team is happy to review your single-line diagram and recommend the optimal switchgear solution.

Changzhou Tuoxin Electric Co., Ltd. — Your single-source partner for complete power distribution solutions. From 12 kV MV switchgear to 400 V LV distribution, we design, manufacture, and deliver certified electrical equipment worldwide.

Send us your project requirements: sale@tuoxinelectric.com WhatsApp: +86 158 6188 2821 | Tel: +86 181 3691 5112