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Mitsubishi J4B-C81-NS servo control PCB angled overview with connectors and digital-display daughterboard
In stock

• Testing Video Provided

$413.00 USD
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More than 100,000 parts in stock & ready for delivery

Mitsubishi J4B-C81-NS is a servo drive control PCB assembly offered for replacement matching. The photographed unit combines a main circuit board, edge-mounted connectors and an upright digital-display daughterboard.

The component side carries BC386A931G51 identification and a MADE IN JAPAN marking. Keep the complete J4B-C81-NS reference when requesting a replacement.

J4B-C81-NS Product Information

Brand Mitsubishi Electric
Model / MPN J4B-C81-NS
Component-Side Board Number BC386A931G51
Reverse-Side PCB Marking BC386A931H01
Product Type Servo drive control PCB assembly
Photographed Configuration Main PCB, connector row and fitted digital-display daughterboard
Visible Connector Labels CN1A, CN1B, CN2, CN2L, CN3, CN4, CN8 and CON1
Condition New, refurbished or used; subject to availability
Testing Pre-shipment test video; test scope confirmed for the quoted assembly
Handling Normally 1–2 business days after payment for confirmed stock
Shipping / ETA DHL, UPS or FedEx worldwide; timing depends on destination and customs
Warranty 1 year for new/refurbished; 3 months for used
Service / Packing Free technical support; anti-static protection, cushioning and reinforced packing

Model and Board Identification

Compare the full model, including C81 and NS, with the original board. Check BC386A931G51, revision labels and fitted components together. The reverse-side BC386A931H01 marking provides a separate PCB reference. A shared base number alone does not establish interchangeability.

Connector Layout and Display Assembly

The photos show two metal-shielded rectangular connectors, black connector housings, a D-sub connector and the long CON1 board-to-board connector. A Mitsubishi MGA031 device is visible in the main logic area. The upright daughterboard carries a digital display. These details help compare the supplied assembly with the original unit.

Match connector positions, keying, mounting holes, daughterboard orientation and installation clearance. Confirm that the quoted assembly includes the display daughterboard and any required fittings shown in the photos.

Replacement Matching and Quotation

Send clear photos of both sides of the original PCB, its complete model markings and the servo amplifier nameplate. Confirm the amplifier specification, board revision and any firmware or configuration requirements before ordering. Exact amplifier compatibility must be checked for the individual assembly.

Include the required quantity, preferred condition and delivery country. Actual-unit photos, supply scope, testing details and dispatch timing can be confirmed with the quotation.

Browse Mitsubishi PCB boards and Mitsubishi servo drives.

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