Hubachse ZH90 mit Greifer für den Schaltschrankbau
Hubachse ZH90 mit Greifer für den Schaltschrankbau
Guide · Control cabinet construction
Ergonomics in control cabinet construction: the right lifting aid for every component
Wiring while standing overhead, inserting mounting plates by hand, and lifting bulky enclosures and subracks single-handedly: Physical strain is part of everyday life in control cabinet manufacturing throughout the entire production process. This guide categorizes typical components and weights and shows which lifting aid is suitable for which task, from a single mounting plate to a complete subrack.
CHAPTER 1
Why control cabinet construction is particularly stressful
Control cabinet construction combines several risk factors, each critical on its own, which then combine to create a cumulative effect. Mounting plates are often assembled while lying down and then lifted vertically into the enclosure, frequently several times per shift and in awkward postures. Wiring involves overhead work or twisted gripping, especially on densely packed enclosure back panels. And the components themselves are unwieldy: large, but not always heavy enough to be automatically recognized as a risk, even though their shape and gripping conditions increase the strain just as much as their sheer weight.
In practice, four recurring stress situations can be distinguished: assembling mounting plates on the workbench, inserting the finished plate into the housing, final assembly of doors and side panels, and transport between the assembly, wiring, and testing stations. Each of these situations has a different stress profile: during assembly, the surface area and tilting during placement are the dominant factors; during insertion into the housing, the constrained posture due to the narrow frame is the primary concern; and during final assembly, the repeated lifting of heavy doors from a squatting position is crucial. Consequently, the most effective lifting aid at each station varies; a single solution for the entire process is rarely sufficient.
CHAPTER 2
Typical weights and components in control cabinet construction
An overview of the weight of common components and what is important for each type of component:
Mounting plates
-
Depending on size and number of components, the weight is usually between 20 and 60 kg. Steel plates weigh significantly more than aluminum versions of the same surface area, which must be taken into account when selecting the load-bearing capacity.
Empty enclosures, small to medium
-
Often 30 to 100 kg, unassembled. Stainless steel enclosures for cleanroom or outdoor applications are at the upper end of this range.
Floor-standing cabinets, subracks and complete assemblies
-
100 to 300 kg, fully equipped and with frame also considerably more, especially in multi-row switchgear systems
Transformers and power supplies
-
usually weighing between 10 and 40 kg, but due to their compact, top-heavy design with a shifted center of gravity, they are still difficult to grip cleanly.
Busbars and cable ducts
-
Their weight is often not a problem, but their length of up to several meters makes them bulky and difficult to position safely without a second person.
Even at the lower end of these ranges, one is approaching the guideline values at which, according to the Manual Handling Regulations, closer scrutiny is required, especially when forced postures and repetitive frequency are involved. The guide " How many kg can you lift?" explains exactly how these limits are determined and how a risk assessment is carried out.
CHAPTER 3
Legal framework: Risk assessment in control cabinet construction
The regulations governing manual handling of loads apply to control cabinet construction just as they do to any other manufacturing process, with one key difference: the key indicator method assesses not only the weight but also posture and working conditions, and both of these factors are often unfavorable in this context. A 25 kg mounting plate lifted into the enclosure from a twisted position above waist height results in a higher risk score than the same load when the worker is standing upright and has good accessibility.
For the employer, this means: The obligation to avoid lifting operations according to §2 para. 1 LasthandhabV often applies in switchgear construction even to weights that seem uncritical at first glance, especially in cycle work with more than ten lifting operations per hour.
CHAPTER 4
Suitable lifting aids for each task
Different solutions from the ZHHT product portfolio are suitable for control cabinet construction, depending on what needs to be moved:
Lifting platform ZH, up to 100 kg
Mobile and battery-powered, ideal for mounting plates at changing workplaces without a fixed compressed air infrastructure, as it can be moved between assembly and wiring stations without installation effort.
Joint manipulator, up to 800 kg
For large housings and assembled modules, pendulum-free guidance during positioning and rotation, important for precise fitting into pre-made frames.
Rope manipulator, up to 150 kg
Easy and quick to access, well suited for transformers, power supplies and other compact, top-heavy components with a shifted center of gravity.
Lifting axle ZH90 and flex arm, up to 1,200 kg and 200 kg respectively
for purely vertical lifting, such as when inserting subracks into rows of cabinets or racks, where lateral swinging would lead to collisions with neighboring cabinets
Custom devices and grippers
Tailored to flat, rectangular components such as mounting plates or housing doors, for secure hold without tilting, with an ESD-dissipative version available for sensitive assemblies if required.
CHAPTER 5
Integration into existing wiring and assembly workstations
A lifting aid must integrate into the existing workflow, not the other way around. The ZH lifting lift can be freely moved between workstations and requires no fixed connection, while the articulated manipulator is positioned stationary at assembly tables or test stations. Both solutions can also be designed for use in cleanrooms, which is relevant for many control cabinet manufacturers in the electronics and automation industries, as is an ESD-dissipative version for assemblies with sensitive electronic components.
Three factors play a role in integration: the working height, which can usually be combined with height-adjustable workbenches; the available space around the workstation, especially with mobile solutions in narrow production lines; and whether an existing line is being retrofitted or a new line is being planned with it in mind from the outset. Both are possible; retrofitting simply requires more precise coordination of the existing space conditions, particularly when several workstations are in series and collision-free operation between adjacent stations must be ensured.
CHAPTER 6
Economic benefits
As with other manual lifting operations, a lifting aid in control cabinet manufacturing typically pays for itself within 12 to 24 months through reduced sick leave, fewer downtimes, and a more stable cycle time on the wiring line. Furthermore, there is an argument that is particularly relevant in control cabinet manufacturing: skilled workers for wiring and assembly are in high demand, and a noticeably less strenuous workplace is a tangible advantage in the competition for these employees, especially for physically demanding tasks such as repeatedly lifting mounting plates.
FAQ / Q&A
Frequently Asked Questions
01 How heavy are mounting plates typically used in control cabinet construction?
Depending on size and configuration, they typically weigh between 20 and 60 kg. Steel plates weigh significantly more than aluminum versions of the same surface area, and the number of terminals, relays, and wiring channels adds further weight. Even at this weight, a lifting aid is worthwhile if the plate is lifted several times per shift, especially if it is being inserted into the housing from an awkward position.
02 Which lifting aid is suitable for control cabinet mounting plates?
The ZH lifting platform, with a capacity of up to 100 kg, is designed for this application: mobile, battery-powered, and usable without fixed infrastructure, making it ideal for use at frequently changing assembly workstations. A device specifically tailored to the panel geometry ensures that the panel does not tilt when inserted into the housing and can be precisely aligned, even with partially wired panels that have uneven weight distribution. The practical example of control cabinet assembly demonstrates how this works in practice at a wiring workstation: Ergonomic lifting aid
03 Can a lifting aid also move large control cabinet housings?
Yes. The articulated manipulator moves loads up to 800 kg without any oscillation, making it suitable for assembled enclosures and complete modules, including positioning and rotation during installation. Especially in multi-row switchgear, where enclosures must be precisely fitted into a pre-fabricated frame, the rigid guide prevents tilting, which is almost unavoidable when lifting hands-free with several people.
04 When does a lifting aid become worthwhile in control cabinet construction?
Not only with very heavy weights. Since the key indicator method also considers posture and frequency, even 20 to 30 kg reaches a critical risk level when repeatedly lifted from an unfavorable position, significantly sooner than with a single lift under good conditions. For shift work with more than ten lifting operations per hour, the obligation to avoid excessive lifting according to the German Ordinance on Manual Handling of Loads (LasthandhabV) generally applies even in the medium weight range of the aforementioned components.
05 How is a lifting aid integrated into an existing wiring workstation?
Customized to suit available space and workflow. Mobile solutions like the ZH lifting platform can be integrated without structural modifications, while stationary solutions like the articulated manipulator are permanently positioned at the workstation. For multiple workstations in series, it is also checked that the swivel range of adjacent stations remains collision-free, which is often the limiting factor with conventional jib cranes and their larger reach.
06 Are Zeilhofer lifting aids suitable for use in cleanrooms?
Yes, both the ZH lifting platform and the articulated manipulator can be designed for cleanroom use, which is particularly relevant for control cabinet manufacturers in the electronics and automation industries. For assemblies with sensitive electronic components, an ESD-dissipative version of the fixture and gripper is also available to prevent electrostatic discharge from affecting the components.
07 Which lifting aid is suitable for transformers and power supplies?
For these compact but top-heavy components with a shifted center of gravity, a cable manipulator with a capacity of up to 150 kg is usually suitable; it is easy to access and can be quickly attached to the component. Unlike a rigid device, the clamping mechanism can adapt to the irregular center of gravity without the component tipping over during lifting.
08 Can a lifting aid also be used for purely vertical stacking in rows of cabinets?
Yes, the ZH90 lifting axis is suitable for this. It guides the load vertically without any pendulum movement and is therefore well suited for inserting subracks into rows of cabinets or racks, where lateral pendulum movement, as occurs with a crane using a rope or chain, would lead to a collision with the neighboring cabinet.
09 How does a lifting aid differ from a classic jib crane in control cabinet construction?
A jib crane or winch holds the load in a swinging position, which poses a collision risk with neighboring stations in narrow production lines with multiple workstations. Furthermore, its reach radius requires significantly more space than is often available in densely packed assembly lines. In contrast, the ZH90 manipulator and lifting axis guide the load rigidly and without swinging, making precise fitting into narrow frames and rows of cabinets practically feasible.
10. In which industries is the use of lifting aids in control cabinet construction typical?
Typical applications include electrical and automation engineering, mechanical and plant engineering, energy technology, and suppliers that manufacture control cabinets for industrial customers. Wherever mounting plates are regularly assembled and inserted into enclosures, a suitable lifting aid relieves the worker and makes cycle times on the wiring line more predictable.
11. How much does a lifting aid for control cabinet construction cost?
This depends heavily on weight and design. The guide to the costs of lifting aids provides an overview of the price ranges.