Bronze Commutator Plate

Commutator plates are the segmented contact elements in commutator-style switching mechanisms, older MV switchgear designs that use a rotating or stepping contact instead of a linear make-and-break action. Bronze (typically aluminum bronze or phosphor bronze) is the standard material because the plates see sliding contact under load: the brush or contact wiper moves across the plate face, and bronze resists wear at the sliding interface better than pure copper.

This SKU primarily serves refurbishment of legacy MV switchgear installations. New designs rarely use commutator-style switching, but installed fleets need replacement plates as the contact faces wear.

Specifications

Property	Value
Alloy	Aluminum bronze C95400 or phosphor bronze C51000 (per drawing)
Form	Flat or curved segment plate (machined to drawing)
Plate Thickness	Per drawing
Plan View Dimensions	Per drawing
Surface Finish	Machined; polished contact face optional
Conductivity	10–20% IACS depending on alloy choice
Hardness (HB)	75–200 depending on alloy and temper
Mounting Features	Holes, slots, locating pins per drawing
Working Voltage	Common MV ratings: 12 / 24 kV (legacy designs)

Exact certified properties for your lot are available with material documentation on request.

Applications

• Segmented contact element in commutator-style MV switching mechanisms
• Replacement plates for installed legacy switchgear refurbishment
• Custom commutator components for specialized switching applications
• Sub-supply to refurbishment service companies maintaining commutator equipment

Technical Notes

Commutator plates handle sliding contact under load. The contact wiper or brush moves across the plate face during switching, and the load current flows through that moving interface. Plate surface finish matters: a polished contact face has lower initial contact resistance but wears differently than an as-machined surface; specify based on the original equipment design.

For legacy refurbishment, exact dimensional match to the original plate is more important than material optimization. If the original plates were aluminum bronze and you're sourcing replacements, stay with aluminum bronze even if phosphor bronze would technically perform better.

Sourcing & OEM

Custom commutator plates to your drawing are routine. Most orders are for legacy refurbishment, send the original drawing or a sample plate; we'll match dimensions and finish.