M2051R-N-R series is industry-standard 2.54mm closed end IDC connector available with integrated polarizing tabs, ranging from 2 pin to 24 pin options for diversified wiring requirements. Different from 180° feed-through IDC, its closed rear housing blocks wire pull-out and eliminates mid-cable daisy-chain wiring, featuring compact 90-degree vertical wire routing to save precious PCB enclosure space for miniaturized equipment.
Built-in polar lugs avoid mis-mating during mass production assembly to cut wiring failure rate; IDC piercing design requires no stripping or soldering, greatly speeding up harness production. Compatible with universal M2545/M2545R PCB header and M2053 dust cap to guard terminals against dust and moisture. Constructed with UL94V-2 flame resistant nylon and optional tin/gold plating contacts, the connector is fully RoHS compliant, ideal for point-to-point wiring, high-vibration household appliances, driver modules and compact consumer electronics internal interconnection.
M2051R-N-R
① ②③④
①M2051: HRB series
②With R(Blank): Closed end 90°
③N: Number of pins: 2-24
④R: With polarizing tabs
| Part No. | Circuits | Dimensions | Part No. | Circuits | Dimensions | Part No. | Circuits | Dimensions | |||
| UL94V-2 | Dim: A | Dim: B | UL94V-2 | Dim: A | Dim: B | UL94V-2 | Dim: A | Dim: B | |||
| M2051R-2-R | 2 | 2.54 | 5.08 | M2051R-10-R | 10 | 22.86 | 25.40 | M2051R-18-R | 18 | 43.18 | 45.72 |
| M2051R-3-R | 3 | 5.08 | 7.62 | M2051R-11-R | 11 | 25.40 | 27.94 | M2051R-19-R | 19 | 45.72 | 48.26 |
| M2051R-4-R | 4 | 7.62 | 10.16 | M2051R-12-R | 12 | 27.94 | 30.48 | M2051R-20-R | 20 | 48.26 | 50.80 |
| M2051R-5-R | 5 | 10.16 | 12.70 | M2051R-13-R | 13 | 30.48 | 33.02 | M2051R-21-R | 21 | 50.80 | 53.34 |
| M2051R-6-R | 6 | 12.70 | 15.24 | M2051R-14-R | 14 | 33.02 | 35.56 | M2051R-22-R | 22 | 53.34 | 55.88 |
| M2051R-7-R | 7 | 15.24 | 17.78 | M2051R-15-R | 15 | 35.56 | 38.10 | M2051R-23-R | 23 | 55.88 | 58.42 |
| M2051R-8-R | 8 | 17.78 | 20.32 | M2051R-16-R | 16 | 38.10 | 40.64 | M2051R-24-R | 24 | 58.42 | 60.96 |
| M2051R-9-R | 9 | 20.32 | 22.86 | M2051R-17-R | 17 | 40.64 | 43.18 | ||||
Key Features
Standard 2.54mm pitch IDC, fits AWG22-26 discrete conductors
Closed end design saves in-board wiring space for compact design
Built-in polarizing tabs avoid reverse incorrect mating
IDC solder-free termination, quick tool-free assembly
Matches M2545 and M2545R PCB header for wire-to-board connection
Fits M2053 cover to protect contacts against dust & moisture
UL94V-2 flame retardant housing, RoHS compliant
Designed to pair with M2053 series housing covers, effectively preventing dust, moisture and foreign debris from damaging exposed contact terminals.
M2051R-N-R: Indirect PCB mating; mates with M2545 and M2545R series PCB headers to achieve reliable wire-to-board interconnection.
Q2: What are the differences in Application: With vs Without Polarizing Tabs?
Answers are below:
①With Polarizing Tabs
Features integrated polarization tabs that ensure correct mating orientation.
Prevents incorrect insertion and reduces the risk of miswiring or connection errors.
Recommended for applications where reliable, error-free assembly is critical.
Available with integrated polarization tabs to prevent incorrect mating and ensure proper connector orientation during assembly
②Without Polarizing Tabs
Standard connector design without polarization features.
Offers greater mating flexibility but requires proper alignment during installation.
Suitable for applications where connector orientation is clearly identified and the risk of mis-mating is low.
Non-polarized versions are also available for applications where keying is not required.
Note: Electrical & IDC crimp performance are identical for both versions.
A: Yes, feed-through structure allows continuous in-line wiring without cutting finished harness.
Q7: What are the advantages of a 90° IDC Closed End connector?
A: Key benefits include:
Higher mechanical reliability due to internal cable termination and reduced stress on IDC contacts.
Compact cable routing, requiring cable exit space on only one side.
Improved signal integrity with minimal cable stubs and reduced signal reflections.
Simplified assembly, as the cable is terminated at a single location.
Typical applications: Point-to-point cable assemblies, control systems, power distribution modules, and industrial equipment.
Q8: Which connector type should I choose, closed end IDC or Feed through IDC?
A: Selection depends on your application requirements:
| Application | Recommended Connector |
|---|---|
| Point-to-point connections | 90° IDC Closed End |
| Space-constrained designs | 90° IDC Closed End |
| High-vibration environments | 90° IDC Closed End |
| Daisy-chain wiring | 180° IDC Feed through |
| Multi-board systems | 180° IDC Feed through |
| Bus or distributed I/O architectures | 180° IDC Feed through |
| Cost-sensitive cable assemblies | 180° IDC Feed through |
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