555.127 MGS-7

555.127 MGS-7 aviation carbon brush

555.127 is the armature drawing number of the carbon brush, not the designation of a complete motor, generator, converter or electromechanism. Keeping those identities separate allows the replaceable contact element to be found without confusing it with the unit in which it operates. The confirmed brush grade for this card is MGS-7, MGS-7i. Applicable units include SGS-40N, NU-2; SGO-ZOU-4S, SGS-40P, PU-2; GSR-ST-12000VT-KU, GSR-ST-12VT-2S.

The brush acts as a sliding current-carrying contact in an electrical machine. Its carbon block runs against a commutator or contact ring, while the flexible lead carries current to the stationary circuit. This construction maintains electrical continuity during rotation, normal vibration and progressive movement of the brush as its working surface wears.

Function and operating principle of the 555.127 brush

In service, the brush-holder spring maintains contact pressure between the block and the rotating surface. The brush must move freely in the holder without binding, and the flexible conductor must not restrict its travel. Incorrect dimensions, an unsuitable grade, inadequate pressure or a damaged lead can cause arcing, local overheating, unstable current transfer and accelerated wear.

Selection by appearance alone is not sufficient. A correct order checks the complete drawing number, material grade, carbon-block dimensions, number and position of leads, terminal form, working-face orientation and holder configuration. A visually similar brush of another execution may not satisfy the electrical or mechanical requirements of the applicable unit.

Verified variants, dimensions and applications

Confirmed application variants: applicable unit SGS-40N, NU-2, grade MGS-7, carbon block 12,5 × 25 × 28 mm. applicable unit SGO-ZOU-4S, SGS-40P, PU-2, grade MGS-7, carbon block 12,5 × 25 × 28 mm, 1 pc per group, 3 groups in the unit. applicable unit GSR-ST-12000VT-KU, GSR-ST-12VT-2S, grade MGS-7i, carbon block 2/3,6 × 17,5 × 25,5 mm, 2 pc per group.

The former catalog page associated this position with these searchable unit references: SGS-40N, NU-2. They are retained for search continuity and old-link verification, while the armature drawing 555.127 is the primary Part Number.

When technical catalogs list several units, grades or dimensions under one drawing, they are presented as confirmed variants inside this single product card. This avoids competing URLs for the same primary Part Number. The required execution must still be confirmed from the maintained unit, removed sample or approved maintenance documentation before supply.

Inspection before installation

Incoming inspection should cover the carbon block, contact face, edges, flexible conductors, lead attachment points and metal terminals. Cracks, deep chips, loose connections, signs of overheating or defects that prevent free holder movement are unacceptable. Dimensions should be measured on the carbon block and should not include lead length unless the drawing defines another method.

After installation, commutator condition, spring pressure, contact-face bedding and allowable wear must be assessed under the maintenance procedure for the applicable unit. Reliable universal values for current density, contact voltage drop, spring force and wear limit across every 555.127 variant were not found in open sources.

Storage, handling and order verification

Before installation, carbon brushes should be kept in dry closed packaging and protected from dust, moisture, oil and accidental mechanical impact. Carbon material is comparatively brittle, so the brush should not be dropped, clamped by its flexible lead or stored under heavy parts. The contact face and terminal should not be ground or treated with aggressive cleaners unless the applicable maintenance procedure requires it, because uncontrolled rework may alter geometry, surface condition or electrical connection quality. Packaging identification should be retained until incoming inspection is complete.

For order verification, a useful inquiry includes a photo of the removed brush beside a measuring tool, a separate view of the terminal and leads, and the designation of the unit and brush holder. Width, thickness and length are measured on the carbon block; flexible-lead length and metal hardware are recorded separately. A worn sample must not be treated as the nominal length. Where one drawing has several listed executions, state the required grade, quantity, brushes per group and known unit modification to reduce the risk of supplying a visually similar but incorrect brush.

Ordering the 555.127 carbon brush

An inquiry should state 555.127, the required grade, dimensions, applicable unit and quantity. The minimum order is 50 pieces. This product is offered in New condition on a pre-order basis with a six-month warranty. Documentation and the exact delivery configuration are confirmed during quotation. More positions are available in the Aviamisto Carbon Brushes category.

Related aviation carbon brushes

Other drawing-based positions available for comparison include 555.133 VT-1, 555.135 MGS-7, 555.143 VT-5, 555.162 MGS-7. These are related products in the same catalog group, not confirmed interchangeable parts. Any replacement must be verified against the armature drawing, material grade, dimensions, lead arrangement and the maintenance documentation for the applicable unit.

Product Type: Carbon brush / electrical machine brush

Designation: 555.127

Alternative Designations: 555.127; 555127; 555 127; 555.127 MGS-7 / MGS-7i

Armature Drawing: 555.127

Brush Grade: MGS-7 / MGS-7i

Applicable Unit: SGS-40N, NU-2; SGO-ZOU-4S, SGS-40P, PU-2; GSR-ST-12000VT-KU, GSR-ST-12VT-2S

Function: Sliding electrical contact and current transfer between rotating and stationary parts of an electrical machine

Confirmed Variant 1: applicable unit SGS-40N, NU-2, grade MGS-7, carbon block 12,5 × 25 × 28 mm

Confirmed Variant 2: applicable unit SGO-ZOU-4S, SGS-40P, PU-2, grade MGS-7, carbon block 12,5 × 25 × 28 mm, 1 pc per group, 3 groups in the unit

Confirmed Variant 3: applicable unit GSR-ST-12000VT-KU, GSR-ST-12VT-2S, grade MGS-7i, carbon block 2/3,6 × 17,5 × 25,5 mm, 2 pc per group

Mass: Reliable data not found in open sources

Current Density: Verify against documentation for the exact grade and execution

Installation: Correct brush holder according to applicable unit documentation

Interchangeability: Not confirmed; verify drawing, grade, dimensions, leads and terminal

Minimum Order Quantity: 50 pcs

Condition: New

Warranty: 6 Months

Stock Status: Pre-Order

Technical Documentation: Armature drawing 555.127 and applicable unit documentation

All shipments are carried out from our international warehouse in Dubai (UAE), as well as from our partners’ remote warehouses.

In Stock — items available in stock at the Dubai warehouse are dispatched within 5–10 business days after receiving 100% prepayment.

Remote Stock — items available at our partners’ remote warehouses are supplied within an average of 30–45 business days after receiving 100% prepayment.

Pre-Order — made-to-order products are manufactured and delivered within an average of 45–60 business days. Payment terms: 50% advance payment to start production, with the remaining 50% paid before dispatch from the Dubai warehouse after full readiness for shipment.

Returns & Changes (Restocking Fee)
For selected items, a RESTOCKING FEE of 10% may apply in case of return, order cancellation, or changes to the order specifications. This condition applies only to certain products and is confirmed at the order approval stage.

Warranty
All products are covered by a standard 6-month warranty.
Extended warranty is available upon request and is agreed individually; it may affect the final product price.