Tulip Contact Selection for MV Switchgear
Tulip contacts are the plug-in connection in withdrawable MV switchgear. The multi-finger spring-loaded contacts that let you rack a breaker in and out without de-energizing the bus. Choosing the right tulip contact comes down to three things: current rating, whether you need arc resistance, and whether your application is standard switchgear or something else (like a surge arrester). This guide walks through the options.
For the full range, see Tulip Contacts. For the deeper tulip-vs-finger form factor decision, see Tulip Contact vs Finger Contact.
Step 1: Current Rating
The rating is set by your breaker design. Match it:
- Tulip Contact 630A: distribution-class withdrawable VCBs at 12/24 kV. The workhorse rating.
- Tulip Contact 630A (Standard Series): cost-optimized 630A for high-volume builds where price per piece matters more than design customization.
- Tulip Contact 1250A: larger feeders, transformer-tap breakers, bus-tie applications.
For ratings above 1250A (1600/2000/3150A), all production is custom, send the drawing. Our current rating guide covers how finger count and ring geometry scale with current.
Step 2: Do You Need Arc Resistance?
Standard tulip contacts use silver-plated copper fingers, excellent for routine plug-and-unplug at MV current, but not built to handle an arc. If your application opens or closes under load (arc exposure during make/break), the copper fingers erode fast.
For arc-exposed plug-in applications, the CuW Tulip Contact puts a CuW tip on each finger. The CuW handles the arc; the copper body handles the current path. This is the right choice when the contact sees more than routine insertion duty.
Decision: routine racking only → standard silver-plated tulip. Arc exposure on make/break → CuW-tipped tulip.
Step 3: Standard Switchgear or Specialty?
Most tulip contacts go into switchgear. But the tulip form factor also appears in surge arrester assemblies, where the duty cycle is completely different (one fail-safe disconnect event vs thousands of switching cycles):
- Surge Arrester Tulip Contact: the disconnector interface contact in MV surge arresters.
- Surge Arrester Contact Assembly: the complete disconnector sub-assembly (tulip + spring + housing).
Don't substitute a switchgear tulip for a surge arrester application or vice versa. The plating thickness and spring tension are optimized for different duty cycles.
Construction Basics
A tulip contact is copper or copper-alloy fingers (silver-plated on the contact surface), held in a ring housing with internal spring loading. The fingers compress radially when the mating stud slides in; the spring provides the contact pressure that keeps resistance low. Higher current ratings use more fingers.
When sourcing, the key specs are: rated current, mating stud diameter, finger count (or "match OEM design"), plating thickness, and spring tension. For refurbishment, supply the original drawing or a sample.
Quick Selection Matrix
| Your application | Recommended product |
|---|---|
| 12 kV distribution VCB, standard duty | Tulip Contact 630A |
| High-volume 12 kV builds, cost-driven | 630A Standard Series |
| Larger feeder / transformer breaker | Tulip Contact 1250A |
| Plug-in with arc exposure | CuW Tulip Contact |
| MV surge arrester disconnector | Surge Arrester Tulip Contact |
| Above 1250A | Custom, send drawing |
Related Reading
- Tulip Contact vs Finger Contact: form factor decision
- Tulip Contact Current Rating Guide: 630A/1250A/3150A sizing
- Tulip Contacts (Category): full product range