Electric chain hoists explained: when to use one and what to look for

Over the last few years, there has been an increase in the use of an electric chain hoist instead of a manual chain block. This is especially true for jobs where lifting occurs often enough that having to pull the hand chain repeatedly is not practical. Most people who work in the lifting industry will know the hierarchy of lifting equipment. The hierarchy begins with the manual chain block for infrequent light lifting work, moves on to electric chain hoists for mid-weight and more frequent jobs, and ends with the wire rope hoist for heavy jobs that are continuous and require multiple cycles. Electric chain hoists fill the gaps in that hierarchy and that hierarchy can encompass a lot of work, including workshop and overhead lifting, fabrication, rigging for theatre and events, hoist installations and maintenance, as well as light industrial and construction work that is fixed and located. When it comes time to choose a hoist, there is a lot that must be considered. A hoist’s capacity is one of the most important factors to consider, but it is not the only one.

Capacity and Duty Rating

Typically, most people begin with capacity. That is, how much weight a hoist can lift. The smallest hoist can lift around 125 kg. The largest can lift 10 tons and beyond. Some of the most popular sizes include 250 kg, 500 kg, 1 ton, 2 tons, and 3 tons. Most people miss the duty rating, which is a better indicator of if the hoist will be able to handle the work that is actually given to it.

Hoists can be classified in two systems: FEM (Fédération Européenne de la Manutention) or its ISO equivalent. In FEM you can find ratings such as 1Am, 2m, or 3m. In the ISO equivalent, those ratings are M3, M4, or M5, respectively. The number indicates a rough estimate of how much work that hoist will be able to do in its lifetime. In FEM, 1Am (ISO M3) is for very light and casual use, and FEM 2m (ISO M5) is for intensive industrial use. For FEM 3m and above, you will be in heavy cycling for industrial use, and those ratings will typically be for wire rope hoists anyway.

The practical point: A 1-tonne hoist rated FEM 1Am and a 1-tonne hoist rated FEM 3m are not the same products. The former is designed to operate twice a week shifting loads to and from a workbench. The latter is designed to operate every hour of every shift, lifting loads several times a hour. Select the wrong duty rating and you will drastically reduce the working life of the hoist. Consider how the hoist will be used, including the average load as a percentage of the hoist’s full capacity, the maximum number of lifts per hour, and the number of hours per work shift. A reputable supplier will assist you in selecting the appropriate duty class using this information.

Single-phase or three-phase

Single-phase electric chain hoists operate on the standard 230V mains and are commonly available up to about 1 tonne, although some manufacturers go higher. They are a good choice for workshops that do not have a 3-phase supply and for portable hire equipment that is moved between domestic supply locations. Three-phase electric chain hoists (400V in the UK) are used above 1 tonne for most product lines and are the standard chain hoists for industrial applications. They feature more efficient motors, run cooler when shifted continuously, and have no upper limit on capacity. Three-phase also ensures reverse-phase protection, which prevents the hoist from operating should the supply be connected the wrong way.

The crossover point is approximately 1 tonne, but it varies. If you have 3-phase supply on site, then it is advisable to take 3-phase supply even for smaller hoists. 3-phase supply hoists have improved duty performance and operating life. If you are restricted to single-phase supply, then you are not necessarily limited to 500 kg hoists, but do consider the duty cycles to which you will be putting the hoist.

Electric hoists in the standard configuration come with hoisting hooks. You can only suspend them from a fixed structure/balance beams, and they lift loads only along a vertical axis and from a fixed point. Many applications only require this.

It is only along the horizontal axis that such hoists require further means of support. The simplest method is a push trolley. Under the application of hand force the hoist traverses along the balance beam. This method is appropriate for short distances and low precision, but as the load becomes heavier it also becomes more difficult to push. The next step is a geared trolley. The trolley also has a hand chain, but a geared mechanism provides a mechanical advantage. Slower than pushing, but significantly easier to pull the load. A fully-electric trolley is better yet. There are two motors, two motions, and the hoist moves laterally and vertically under power. This is standard for overhead crane installations.

Safety features and inspection

A decent modern electric chain hoist design incorporates several important safety features. The main one is the DC electromagnetic brake. Because these brakes are powered by the load current, they are normally closed, which means that in the event of a power outage, the brake holds the load instead of letting it fall. Another important feature is the slip or friction clutch. It is designed to slip if the load exceeds the rated capacity of the hoist. However, it should be noted that in some cases of this design, the slipping occurs more often than the manufacturer specifications suggest. To protect against traveling past the safe points, upper and lower limit switches are included. For three-phase hoists, a reverse-phase relay and a thermal overload protection for the motor are provided. Hoists should be rated at IP55 or higher; anything lower is rated for use in a workshop only.

A competent inspector should examine a hoist at least every 12 months, with more frequent examinations if the hoist is used for lifting people. There should be daily pre-use inspections and periodic inspections by a competent person. The frequency of inspections should be greater if the hoist is used more frequently.

Purchasing Notes

When it comes to buying something as opposed to renting it, you have to really assess brand and parts availability, genuine duty rating, and good paperwork. Manufacturers like Yale, Kito, Stahl, Demag will have parts and service support in ten years; cheap, unbranded units from the marketplace will not, and when they will need a contactor or limit switch, they will be scrapped. Hoists sold with favourable FEM ratings should also be handled with care. Suppliers that actually care about the product will let you know what their unit can actually do, not just what it will do in theory.

For most tasks on most sites in the UK, an electric chain hoist is a smart buy in comparison to a rope hoist (which offers more flexibility but adds cost, complexity, and effort for maintenance over an electric hoist) or a manual chain block. Most lifting is done in the middle of the range.