Product Overview

This Hirschmann angle sensor reads boom angle on crawler cranes, mobile cranes and rotary drilling rigs and passes that value to the machine's load moment indicator. It is a small item on a long construction machinery spare parts list, but when it stops reporting, the machine stops lifting. The working range is 0–180°, enough to cover a boom from fully lowered to fully raised, and the unit measures across 0–360° at a resolution of 0.05°, so a slow movement still registers as a change.

Power comes from 9 to 36 VDC, which covers both 12 V and 24 V systems, and the operating range runs from −40 °C to +85 °C. That spread matters on a machine that starts before dawn in winter and sits in the sun all summer: the angle input should not be the first thing to become unreliable. The housing is aluminium, and the unit is CE certified to EN 61000-6-2 for immunity and EN 61000-6-4 for emissions — the standards that decide whether it behaves with welders, radios and alternators working nearby. Because it is one of the crane electrical components rather than a mechanical linkage, the reading comes from the electronics rather than from a sliding contact.

Most orders are straight replacements after a failure. A sensor that drifts, sticks on one value or drops off the bus will hold up a lift, and the quickest way back is a unit that matches the one already on the boom rather than a re-engineered installation. Nothing on the hydraulic crane parts side has to be touched, no hose has to be broken, and the machine goes back to work on the wiring it came in with.

Buyers are usually keeping a working fleet running: fleet maintenance managers, independent crane workshops and regional distributors who hold crawler crane parts for the brands they serve. Some are chasing a fault in the middle of a shutdown; others are refreshing an ageing safety system and want the angle input to be the dependable part of it.

As crane parts suppliers we would rather check a photo of your old unit than let you guess between two similar builds. A few minutes of matching beats a sensor that sits on the shelf because the connector was wrong.

Key Features

• CANopen output. The sensor reports digitally on the machine bus, so the controller reads a number rather than a voltage that shifts with temperature and cable resistance. Wiring becomes a bus connection instead of a set of scaled analogue signals.
• 9–36 VDC supply. One unit covers 12 V and 24 V electrical systems, and the wide band leaves room for the voltage dips that come with cranking and sudden loads.
• 0.05° resolution. Small steps register, so a boom easing through a slow lift still shows movement on the display, and the same physical angle reads the same way every time you return to it.
• Aluminium housing. A metal body copes with the vibration and knocks a boom-mounted part collects over a working life.
• −40 °C to +85 °C operating range. Cold starts and heat-soaked engine decks both sit inside the specification, which matters on a machine that works outdoors all year.
• CE EMC compliance. Immunity to EN 61000-6-2 and emissions to EN 61000-6-4 are the parts of the specification that decide whether the reading stays steady while a welder is running on the deck.

Specifications

Boom Angle in the Safety System

A load moment indicator works from three live inputs: boom angle, boom length and the load on the hook. The controller compares them with the rated capacity curve for the current configuration and shows the operator what can still be lifted. The angle sensor supplies the first of those figures, and the crane load indicator uses it to work out the working radius and the safe load at that radius. An error at this input runs through every number downstream.

The unit sits where the boom hinges. On a crawler it is at the boom foot or on the luffing frame; on XCMG and ZOOMLION truck cranes it is one of the mobile crane parts that has to be right before the limiter will allow a lift, mounted at the boom pivot. The reading travels over the CANopen bus to the cab display and to the limiter, which is why a bus fault and a sensor fault can look identical to the operator.

Failures tend to announce themselves. The angle freezes at one value while the boom is moving, wanders a degree or two between shifts, jumps as the machine crosses rough ground, or the display raises an angle or communication fault and the limiter refuses the lift. A rubbed cable bundle, a corroded pin or water in a connector can produce exactly the same symptoms as a dead sensor, so walk the cable run before condemning the unit.

The other inputs deserve the same attention during a repair. If the load cell or the length sensor is also past its serviceable life, the system will keep faulting after the angle sensor has been changed, and a second shutdown costs more than the parts. That is why we ask what else is on the machine — one enquiry covering the whole set of crane electrical components usually proves more cost-effective than replacing them one at a time.

Installation & Commissioning

1. Isolate the machine and lock out the cab controls. Note the boom position before you start so you can return to the same geometry for the check afterwards.
2. Photograph the old unit in place — faceplate, mounting plate, lever and connector — before anything is loosened, so the replacement goes back the same way.
3. Release the wiring at the connector rather than pulling on the cable, then check the pins for corrosion or pushed-back terminals while it is apart.
4. Take out the perimeter screws and lift the sensor off its plate. Keep the bracket and any shims as they were, and look for cracks or distortion in the plate before fitting the new unit.
5. Seat the replacement on the same plate with the lever in the same position as the old one, then tighten the screws evenly around the rim.
6. Reconnect the wiring, confirm the latch engages, and secure the cable so it cannot chafe against the boom structure as the boom moves.
7. Power up and watch the angle value on the display. It should follow the boom smoothly through its full travel, with no jumps or dropouts, and the crane load indicator should accept it without a fault code.
8. Check the reading against a digital inclinometer at two positions — boom fully down and at a working angle — and calibrate the reference in the controller the way the machine's manual sets out.

Identifying the Right Variant

• We do the matching. As crane parts suppliers we would rather look at your old unit than have you choose between two similar builds from a list.
• Read the label first. The blue faceplate carries the Hirschmann name and the unit's type markings; a clear photo of that face is the quickest way to confirm which build is on the machine, even where the label is scuffed.
• Photograph the mounting. The unit sits on an octagonal plate held by screws around the rim, with a small lever at the lower edge. Hole spacing, lever position and the bracket behind the plate all have to line up.
• Show the connector. Pin count and keyway on the wiring plug must match the replacement; a photo of the plug face and the cable entry prevents a return.
• Truck cranes. XCMG and ZOOMLION truck cranes go through the same process, and a mobile crane parts enquiry moves faster when the boom photo and the plate photo arrive together.
• Crawler machines. FUWA crawler cranes and SANY rotary rigs account for most of these sensors; as with any crawler crane parts request, the old label and the machine serial settle it.
• Older machines. On early equipment the original build can be long out of production, and construction machinery spare parts for those years are often gone, so send what is left of the old unit and we will look for a current equivalent.
• Say what it is doing. Sticking, drifting, fault codes, a blank display — the symptom tells us whether you need a sensor or whether the cable is the real problem.
• One message, several items. If the shutdown also needs a load cell, a length sensor, hydraulic crane parts or other crane spare parts, list them together so they can be packed and shipped as one consignment.

Care & Field Checks

1. Wipe the faceplate and lever with a damp cloth at service intervals, and keep a pressure washer away from the sensor and its connector.
2. Check the perimeter screws for tightness. Vibration works them loose over time, and a loose plate lets the lever move independently of the boom.
3. Follow the cable along the boom and look for chafe where it passes through guides or crosses a joint, then check the connector for corrosion after wet or dusty work.
4. Compare the displayed angle with a known boom position now and then. A slow drift over months is the earliest warning, and it is easier to catch before the limiter starts faulting.
5. Keep a spare on the shelf among your other mobile crane parts — a sensor failure stops a lift, and one spare keeps a fault from turning into a lost shift.
6. Check the machine, not only the part. If the boom itself is slow or uneven, the fault is likely in the hydraulic crane parts that drive it; the angle value will still track smoothly while the boom lags behind it.

Ordering & Delivery

Technical Support & Model Matching

Not sure which part matches your machine? Send us the model, serial number and the original part number — or a photo and key dimensions — and our engineers will confirm the correct item and check availability before you commit. They have spent more than ten years in construction machinery and can talk you through fault-finding, installation and commissioning by phone, email or video. We also trace parts for discontinued and legacy models. Support runs 24/7 from Shenyang, China, where we have been supplying buyers since 2017.

FAQ