3-1 Limit Locator (3-1A / 3-1B)
Lightweight 6082 aluminum locator that clamps the contact wire and limits its uplift at registration points.
Specifications
| Model | 3-1A / 3-1B |
|---|---|
| Drawing No. | 3-1A |
| Standard | TB/T 2075.3-2024 — Part 3: Limit-type positioning devices |
| Design Speed | ≤250 km/h (3-1A, round section) / 250–350 km/h (3-1B, rectangular section) |
| Installation | Fitted on the registration bracket, clamping the contact wire and limiting its uplift |
The 3-1 limit locator is the registration member of a limit-type positioning device for electrified railway overhead contact systems. One end grips the contact wire through the registration clamp; the other end hooks onto the registration bracket on the positioning tube. Its stop face works against the bracket so the dynamic uplift of the contact wire is limited to the designed value while lateral stagger is held.
Types are 3-1A (straight tube) and 3-1B (bent tube, available with round or rectangular tube section): the round section serves lines up to 250 km/h, the rectangular section serves 250–350 km/h high-speed lines, graded per the TB/T 2075.3-2024 load system. The tube body is 6082 aluminum alloy, keeping the concentrated mass at the registration point low.
Design Features
- Reliable stop structure effectively limits dynamic contact wire uplift
- Lightweight 6082 aluminum tube reduces the concentrated mass at the registration point
- Standard interfaces with registration clamps, registration brackets and positioning tubes
- Smooth body surface avoids hard rubbing against the pantograph strip
The product is manufactured under CRCC railway product certification and an ISO 9001 quality management system, with incoming material inspection, in-process control on critical operations and batch-by-batch final inspection before delivery.
Henan Chuangwit Railway Equipment Co., Ltd. supplies this locator with selection calculations, matched fittings and site technical guidance for traction power projects. It clamps the contact wire at the registration point and, through its stop face working against the registration bracket, limits how far the wire may rise when the pantograph passes — protecting the overhead system while keeping stagger stable. 3-1A is the straight-tube type; 3-1B is the bent-tube type, made with a round section for lines up to 250 km/h or a rectangular section for 250–350 km/h high-speed lines. The choice follows the OCS cross-section design and line speed. The 3-4A registration clamp grips the contact wire at the locator end; both are standard TB/T 2075.3 parts designed to work together. Yes — Chuangwit locators are produced under CRCC railway product certification with ISO 9001 quality management, and type test documentation is available on request.Frequently Asked Questions
What does a limit locator do?
Which type should I choose, 3-1A or 3-1B?
Which clamp holds the contact wire?
Is the locator CRCC certified?
Performance
Operating Conditions
Outdoor service at OCS registration points on mainline, high-speed and station structures, subject to suspension, wind, ice and dynamic pantograph loads as defined by the OCS design.
Mechanical Performance
Stop face geometry limits contact wire uplift to the design value under dynamic pantograph passage; aluminum body keeps the registration point light for high-speed duty.
Applications
250–350 km/h Lines
Rectangular-section 3-1B for high-speed duty.
≤250 km/h Lines
Round-section variants for conventional lines.
Station Tracks
Compact stop geometry suits multi-track stations.
Wind & Ice Regions
Uplift held within limits under combined loads.
