Colton Downshop Conductor Systems: Crane Busbar & Power Supply
Colton is a crane busbar system, or crane conductor bar: rigid, finger-proof conductor bars that run along the crane runway and supply power to overhead cranes, hoists and travelling equipment through a sliding collector, with no trailing cable. It is Granada's own design, built in the UK for over 40 years and exclusive to Granada Cranes.
What is a crane busbar system?
A crane busbar, or crane conductor bar, is the crane power supply for equipment that moves. Insulated conductor bars are fixed along the runway or bridge, and a collector head on the crane or hoist slides along them, picking up power wherever the crane travels. Compared with a festoon or trailing cable there is nothing to snag, wear or replace, which is why a conductor bar system is the usual choice for crane electrification on long runways, high duty cycles and hot or dusty sites. Colton is Granada's version, and the rest of this page is about why we built it and how it is put together.
Oldest and safest finger-proof bar
One of the oldest and safest finger-proof conductor systems on the market, with more than 40 years of development behind it. The bar profile shields the live conductor so it cannot be touched, which is what "finger-proof" means.
Most believe never bettered
Designed to rival Insul-8 and protected conductor systems when it launched, and copied since. Customers who moved to other makes are returning to Colton year after year.
Designed, stocked and supported by us
Granada holds the Colton tooling and stock. Complete busbar systems are usually available within 2 to 3 days, and every spare is on the shelf at our Oldbury depot.
Colton conductor bar system at a glance
The figures below are the ones our engineers work to. They are also the reason Colton costs less to install than most other four-bar systems.
| Bar variations | 100A and 200A galvanised steel bar; 250A copper bar |
|---|---|
| Section length | 4.5 metres per section of bar |
| Support brackets | One bracket every 2.25 metres. This wider spacing reduces both material and labour cost compared with other four-bar systems |
| First bracket | 150mm from the end of the run, not the 500mm commonly assumed. This gives extra support to the joints |
| Bar spacing | 65mm preferred; 50mm minimum |
| Feed | End fed or centre fed |
| Expansion | Expansion joint required at 90 metres. One set of support clips near the centre should be support clamps, so the system can expand naturally in either direction |
| Maximum run length | TBC |
| Voltage rating | TBC |
| Number of poles | Four-bar system as standard TBC |
| Availability | Complete systems usually within 2 to 3 days. Spares ex-stock, dispatched same day or next day, or collected from Oldbury |
Colton compared with conventional conductor bar
Colton was designed in the first place to do a better job than the conductor systems of its day. These are the differences that still matter.
Finger-proof by design
The Safe-T-Bar profile keeps the live conductor out of reach. It was one of the first finger-proof bars on the market and remains one of the safest.
Fewer brackets, less labour
Brackets every 2.25 metres instead of the closer spacing other four-bar systems need. Fewer brackets means less steel, fewer fixings and faster installation.
Stronger joints
Placing the first bracket 150mm from the end supports the joint properly. It is a small detail that most systems get wrong.
Everything from stock
Hangers, joints, covers and collector heads are all on the shelf. A full system in 2 to 3 days and a spare in the post the day you order it.
Customers come back
Since 2021 Colton sales have grown every year, with many customers returning from other makes including Hamilton POW-R-SAFE.
Backed by crane engineers
Colton is supplied by the company that also designs, installs and services the cranes it powers, so the busbar is specified as part of the crane, not bolted on afterwards.
Made in the UK
Designed and built in Britain for over 40 years, with the tooling held by Granada.
Proven for 40+ years
The bar shape that caught on in the 1980s is the same one running on cranes today. It has not needed changing.
Crane electrification for new installs and retrofits
Colton supplies power to any equipment that moves along a fixed path.
Retrofits and upgrades
Replacing worn festoon, trailing cable or older conductor bar on an existing crane as part of crane modernisation.
Harsh environments
Hot, dusty and high-duty sites where cable systems wear out.
Long runways
End or centre fed, with expansion joints at 90 metres for long runs.
Every Colton spare, ex-stock, same day.
All Colton spares, hangers, joints, covers and collector heads are held in stock. They are usually dispatched on the day of order, or next day at the latest, and can be collected from our depot in Oldbury during office hours. Complete systems are usually available in 2 to 3 days.
A potted history
Colton was founded in 1937 in Derbyshire by the Bowman family, and started out selling domestic equipment. The company then found a market making power connectors for a local fork-lift truck manufacturer. From there it moved into the crane market and designed and manufactured a new-shaped finger-proof bar to rival Insul-8 and protected conductor.
The new bar shape soon caught on and the company opened an outlet in the heart of the industrial Midlands. They first approached Bob McLoughlin to run the new business; he declined and suggested his brother Lawrence instead.
Working from small premises in Tividale, the Midlands business quickly grew into the largest supplier of finger-proof bar in the region. When David Bowman retired and passed the company to his son, the business was rationalised and Lawrence was made redundant. The change did not work, and Colton Electrical went into liquidation in 2010.
Lawrence bought the stock and tooling from the receiver and carried on from home until Granada Midlands became involved in 2012. In 2021 Granada set out to rebuild the Colton customer base, starting with Lawrence's original customers. Sales of bar have grown every year since, as previous customers return and new ones are found, many of them moving back to Colton from Hamilton POW-R-SAFE and other makes.
- 1937: Colton founded in Derbyshire
- Finger-proof Safe-T-Bar designed to rival Insul-8
- Midlands outlet opens in Tividale
- 2010: Colton Electrical enters liquidation
- 2012: Granada Midlands takes on the stock and tooling
- 2021: customer base rebuilt; sales growing every year since
Busbar system supply, installation and support
Tailored to the runway
Bar rating, feed position, bracket layout and expansion joints designed to your runway length, crane duty and building.
Installed by crane engineers
Fitted and commissioned by the same engineers who install and service the crane, so the busbar and the crane are set up together.
Reliable components
Hangers, joints, covers and collector heads that have been proven on cranes for more than 40 years.
Supported for life
Same-day spares from Oldbury, and servicing and LOLER inspection for the crane it powers.
Controls, power and accessories
Festoon Systems
Cable-based crane power supply for shorter runs and control cores.
View rangeCrane Radio Remote Control Systems
Ikusi, Autec and Cattron radio controls for any crane.
View rangeLifting Scales & Weighing Systems
Crane scales and load monitoring.
View rangeLifting Magnets
Magnetic lifting for plate, billet and scrap.
View rangeLifting Plate Clamps & Grabs
Clamps and grabs for plate and section handling.
View rangeLifting Coil Hooks
C-hooks for coil handling.
View rangeAlso in the range: Lifting Tool Box Kits.
We've got answers
A crane busbar, also called a conductor bar system, is a run of rigid insulated conductor bars fixed along the crane runway or bridge. A collector head on the moving crane or hoist slides along the bars and picks up power, so the crane can travel the full length of the runway with no trailing cable. Colton is Granada's own finger-proof crane busbar system.
A festoon carries flat cable on trolleys that concertina along a track as the crane moves. A busbar has no moving cable: fixed bars along the runway and a collector on the crane. Busbar suits long runways, high duty cycles, dusty or hot environments and anywhere cable wear or snagging is a problem. Festoon suits shorter runs and where control cores need to travel with the crane. We supply both.
Yes. Colton is regularly fitted to existing cranes and runways to replace worn festoon, cable or older conductor bar, as well as on new installations. We survey the runway, supply the bar, brackets and collectors, and install and commission the system.
Colton is available in 100A and 200A galvanised steel bar and 250A copper bar. Each section is 4.5 metres long with a support bracket every 2.25 metres, and an expansion joint is fitted at 90 metres. Systems can be end fed or centre fed. Maximum run length: TBC. Voltage rating: TBC.
Yes. Colton was designed and built in the UK from the start, in Derbyshire and then the West Midlands, and Granada holds the tooling today. Complete systems and all spares are supplied from our depot in Oldbury. [CONFIRM WITH GRANADA: where the bar is manufactured today.]
Yes. We supply Colton on its own for customers and contractors who fit their own systems, and we install and commission it with our own engineers as part of a new crane, a runway upgrade or a crane electrification retrofit.
Looking for a new crane conductor system?
Tell us the runway length, the crane duty and whether it is a new install or a retrofit, and we will specify the bar rating, feed and bracket layout and come back with a price. Full systems in 2 to 3 days.
