Category Archives: The Consulting Room

Is your lift installation starting to fail…

…starting to fail for unknown reasons?

If it is, be sure to consider this…

Voltage power optimisation (VPO) has received increasing interest as a means of reducing electricity bills – with savings of 10 to 20% often being claimed.

VPO products balance phase voltage, filters harmonics / transients and reduces input voltage.

Great in theory but not in all practices.

Lower voltages on some motors will increase current and therefore increase costs. A number of companies are offering this type of energy saving product to the market.

Amongst these are companies who offer to simply reduce the voltage of the incoming supply to the building, thereby claiming to save energy.

This involves reducing the voltage at the supply to a value that is within the theoretical acceptable limits currently used for new electrical equipment but may be outside the design limits or initial setup of older equipment such as a lift.

Voltage Optimisation is great for constant impedance equipment such as lights, heaters, etc. but not good for constant horsepower equipment e.g. lift and pump motors.

Lift control systems and drives contain components such as relays, contactors, electromagnetically operated brakes, induction motors, DC motors and solid state drives such as Variable Frequency and Static Converters. Many of these components may have been selected to operate on a nominal 415 volt 3 phase supply to the lift.

If the supply voltage changes significantly, then some component characteristics may change to the point that the lift becomes unreliable or will not run.

In theory reducing incoming voltage by introducing Voltage Optimisation could be a major problem. This is particularly true on all lifts installed prior to 1995. In 1995 an EU initiative to allow free trade across EU boundaries was introduced, therefore motors, controllers, etc. were designed to operate over 380 – 415 volts, not 415 volts or more. (Same with domestic equipment in your home, note rated voltage is now 230 not 240).

Traction Lifts prior to the introduction of Variable Frequency drives required a high torque to start the machine to enable the load to be lifted. Torque is proportional to the square of the input voltage. Therefore; reducing the voltage will reduce the torque, the reduction is not pro rata and a small decrease in input voltage may result in a high torque loss.

Power dips may cause problems and lifts may be unable to lift full loads and motors may stall. A Variable Frequency drive fitted to an old type traction lift motor may work but is not guaranteed due to the poor efficiency of the older machines.

Variable frequency drives input current will increase in order to maintain the rated load and speed of the lift. This may overload the drive and the supply voltage supervision in the drive may shut down due to the reduced input voltage.

Hydraulic lifts (goods, goods passenger and passenger lifts) fitted with Ziehl Abegg oil submerged motors will operate over a range of 380 – 415 volts and there should be no issues even on lifts installed before 1995. Other motors such as Leroy Somer, Rexroth, Brook Crompton Parkinson and Elmo installed prior to 1995 may not provide sufficient torque to turn the pump.

If you are getting feedback on lifts not lifting full loads, fuses or overloads popping (motors stalling) or hydraulic lifts cutting out due to high oil temperature(lifts running at 380 volts actually require more current, therefore oil will get hotter). Then the cause may be attributed to the introduction of Voltage Optimisation. It is also true to say that poor maintenance, old oil on geared traction machines may also cause problems as well.

Contactors and relays may not energise correctly causing chatter and thermal overload of contacts, this will ultimately lead to lift failure.

If you discover an unusual increase in lift failures that leads you to believe the supply voltage may be suspect you should make enquiries in relation to voltage reductions systems that may have been installed. Do not assume that because voltage reduction measures have been installed there is a voltage problem. Many systems are sophisticated and will ensure the voltage is suitable and stable. If however you suspect an issue, a voltage analyser may be required to be installed on the lift supply to record the findings and enable the root cause to be identified.

Individual cases should be reviewed accordingly. However a simple solution would be to make sure the lift supply is connected to the input side of the Voltage Optimisation System and not the load side.

For more expert advice relating to your lift power problems… or any other matters, please  feel free to call us on UK 01483 215 215, Intl: (0) 1483 215 215.

Lift Energy Efficiency

Energy Effiiciency Classification

In these days of reducing carbon footprint and trying to limit the growth of the hole in the ozone layer, energy consumption is an essential key driver in building design and operation. Under European legislation, all buildings will be required to have a 20% energy saving by the year 2020 compared to the energy consumption levels in 2005.

Lifts and escalators in a building contribute on average 3% to 8% of the buildings energy consumption so greater energy efficiency in this equipment will be a key factor in achieving the overall energy targets.

Most of us have seen the A to G energy efficiency charts on the side of electrical appliances or even on adverts of houses that are for sale, these same principles will now be applied to Lifts, escalators and moving walkways. Some manufacturers have adopted the German Standard VDI guideline 4707 Part 1 which forms the basis for assessing and identifying the energy performance of lift systems.

Although this is not a European standard, other component manufacturers and Lift manufacturers are also using this standard so that they are able to compete in the German market. This has led to this guideline quickly becoming a worldwide recognised standard for energy efficiency of lifts.

The two key elements to vertical transport energy efficiency are product design and component design. Manufacturers have looked at items such as regenerative drives and utilising Variable Frequency / Variable Voltage motors for operating the moving elements of lifts and escalators.

In addition they are utilising LED lighting and lighter materials to reduce the energy consumption when the lift is operating. They are even looking at design issues such as counterbalance design to try and to see if in certain situations they can counter balance the lift at less than the normal 50% of car weight as this reduces energy consumption.

Obviously lifts and escalators use a large amount of energy when being used but more emphasis is starting to be given to the energy they consume when they are not being used. Surprisingly studies have concluded that lifts actually use more energy when they are not moving than when they are moving.

Manufacturers are having to introduce sleep modes in their control systems to switch off items such as lighting or fans when not in use. Escalators and moving walkways are also being manufactured to operate at a reduced speed when not in use.

It is not only new equipment that can take advantage of energy efficiency. Lift and escalators can be modernised with similar components and control systems to dramatically reduce their energy consumption. Well maintained equipment will also have greater energy efficiency as well lubricated and adjusted equipment means it runs smoother and uses less energy.

Manufacturers, suppliers and service companies who are embracing these challenges are gaining a serious competitive edge over their less enlightened competitors. Building owners are demanding greater energy efficiency and are starting to ensure that their vertical transport will cost them less in the long run.

Is your lift, escalator or moving walkway as energy efficient as it should be?

For advice and guidance on these and other matters, please feel free to call us on
UK: 01483 215 215, or Intl: (0) 1483 215 215.

Lift standards

Lift standards EN 81-20 and EN 81-50

Introduced in August 2014, two new European standards for lift design and manufacture will bring considerable benefits in terms of accessibility and safety for both passengers and service engineers. The first, EN 81-20:2014, sets out revised and updated safety requirements for the construction and installation of lifts. The second, EN 81-50:2014, defines the test and examination requirements for certain lift components.

The new standards also clarify and improve the current building interface requirements. They replace the current EN 81-1 and EN 81-2 standards introduced in 1998, and all lifts taken into use after 31 August 2017 will be required to comply with the requirements of the new standards.

This factsheet gives an overview of the main changes to the safety requirements introduced in EN 81-20:2014 and EN 81-50:2014. For full details, customers should refer to the official standards documents.

Safety requirements for passengers

Requirements related to Unintended Car Movement (UCM) and ascending car over-speed

The requirements for the protection mechanism that address the risk of the car moving away from the landing have been enhanced, and the requirement for protection against ascending car over-speed has also been extended to cover rescue operations. Contractors must already have lift solutions available that include standard features to address unintended car movement through automated daily testing of the hoisting machine’s brake torque and capacity. Contractors must also include standard features that address the risk of uncontrolled speed when the car is ascending.

Door detection systems

To reduce the risk of doors striking passengers while they are entering or exiting the car, the updated standards require lifts to incorporate a curtain of light mechanism – a non-contact detection system that is designed to prevent the doors from closing if an obstruction is detected. Photocell-based mechanisms will not be compliant with the new standards.

Lift car door locking mechanism

The updated standards require lifts to incorporate a car-door locking mechanism that aims to prevent the doors from being opened from inside when the car is outside the unlocking zone – i.e. when it is not in close proximity to the landing doors. This requirement has been introduced to prevent entrapped passengers from accidentally falling into the lift shaft if they attempt to escape from a lift that has stopped outside the unlocking zone. Contractors must offer this type of mechanism, fulfilling the updated requirements for all its lift solutions.

Fire classification of lift car materials

The requirements for the materials used for car floors, walls, and ceilings have been updated in the new EN 81-20:2014 standard. These materials must meet stricter fire classification requirements according to EN 13501-1. The minimum classifications are as follows, where C and Cfl refer to the ‘reaction to fire’ classification, and s and d refer to the classification of materials with regard to smoke and the formation of flaming droplets/particles, respectively.

  • Flooring: Cfl s2
  • Walls: C s2, d1
  • Ceiling: C s2, d0

Car and landing door and wall strength

The EN 81-20:2014 standard includes updated strength requirements for both landing and car doors, as well as car walls. Doors must now include retainers to keep the door panels in place if the main guiding elements do not operate as intended. Car and landing doors must also be tested to withstand an impact force equivalent to the impact of a person colliding with the door at running speed. The strength requirement of the car walls is such that they must be capable of withstanding forces that are equivalent to a person pushing against them.

Car and shaft lighting

The EN 81-20:2014 standard requires higher levels of lighting for the car interior and the shaft, with the aim to enhance passenger safety and accessibility. In-car lighting must now provide an illumination intensity of 100 lux instead of 50 lux, and emergency in-car lighting 5 lux for one hour instead of 1W for one hour. To enhance safety for service engineers, the new requirement for emergency lighting on the car roof is now 5 lux for one hour. The new requirements for shaft lighting are as follows:

  • Minimum 50 lux 1 meter above the car roof within its vertical projection
  • Minimum 50 lux 1 meter above the pit floor everywhere a person can stand, work, and/or move between the working areas
  • Minimum 20 lux outside of the locations defined above, excluding shadows created by car or components

Safety requirements for service engineers

Pit and machine-room access, and control-station location

The EN 81-20 :2014 standard introduces a number of requirements that aim to make accessing the lift machine room and working in the pit safer for service engineers. Access aids such as ladders now have defined dimension, strength, and location requirements. The access requirements for pits deeper than 2.5 m are now stricter, and an access door may be required.

The standard also requires a control station to be located in the pit, to prevent engineers from having to use ladders or stools in order to reach the components under the car. The control station must be located near the pit’s refuge spaces. There must also be a reset function outside the shaft.

Access, inspection, and rescue doors, and counterweight safety gear

The EN 81-20:2014 standard requires access or inspection doors instead of inspection “trapdoors” to address safe and easy access for engineers. The new requirements are as follows:

  • Machine-room and shaft access doors shall have a minimum height of 2 m and a minimum width of 0.6 m.
  • Pulley-room access doors shall have a minimum height of 1.4 m and a minimum width of 0.6 m.
  • Access trapdoors for engineers to machine and pulley rooms shall give a clear passage of at least 0.8 m x 0.8 m and shall be counterbalanced.
  • Emergency doors shall have a minimum height of 1.8 m and a minimum width of 0.5 m.
  • Inspection doors shall have a maximum height and width of 0.5 m.

The new standard also requires the counterweight to be fitted with a safety gear in cases where there are accessible spaces under the pit – for example, where the pit is located above a parking garage or basement storage space.

Car roof and pit refuge spaces

The volume requirements for the safety refuge spaces on the car roof and in the pit have been increased. The new volumes are as follows:

  • Upright position: 0.4 x 0.5 m (horizontal dimensions), 2 m (height)
  • Crouching position: 0.5 x 0.7 m (horizontal dimensions), 1 m (height)
  • Laying position: 0.7 x 1.0 m (horizontal dimensions), 0.5 m (height) for pit only

The EN 81-20:2014 standard now requires that the landing door providing access to the pit must be able to be opened from the shaft so that engineers can exit the lift shaft, even if the relevant landing door would be closed.

Car roof balustrades

Balustrades located on the lift car roof now have defined strength requirements and updated height requirements. These new requirements have been introduced to reduce the risk of engineers falling into the shaft while working on the car roof. The new requirements are as follows:

  • Where the distance between the inner edge of the balustrade handrail and the shaft wall is up to 500 mm, the balustrade must have a minimum height of 700 mm.
  • Where the distance between the inner edge of the balustrade handrail and the shaft wall exceeds 500 mm the balustrade must have a minimum height of 1100 mm

Horizontal projection into the shaft

Any horizontal projection (ledge) from a wall into the shaft, or horizontal beam greater than 150 mm wide – including separator beams – must be protected so that a person cannot stand on it, except when access is prevented by a balustrade on the car roof that meets the requirements stated above. This exception does not apply for ledges around the pit, for example with a partially enclosed lift shaft.

Changes affecting building design

The EN 81-20:2014 standard introduces some changes to the requirements that the building designer is required to fulfil. These changes all apply to the lift shaft, and are as follows:

  • All glass used in the lift shaft must be laminated.
  • Shaft walls to withstand 1000N
  • Shaft ventilation is now the responsibility of the building designer. The lift manufacturer must provide all the necessary information about, for example, the heat emissions of lift components. This approach facilitates energy-efficient building design, where ventilation requirements are determined based on the most energy-efficient solution, while at the same time taking into account working conditions for engineers working in the lift shaft, and the comfort of passengers inside the car.
  • A fire extinguisher can be located in the shaft. Activation of the sprinkler shall only be possible, when the lift is stationary at a landing and the main switches of the lift and lighting circuits are automatically switched off by the fire or smoke detection system.
  • Pits which are more than 2500mm deep must be served by a permanent stair way not a pit ladder.

More information

For full details of the new standards, you should refer to the official EN 81-20:2014 (E) and EN 81-50:2014 (E) standards documents. Or call Michael Bottomley 07973 301181.

Risk Assessments and Method Statements

The basis of British Health and Safety Law is the Health and Safety at Work Act 1974. The Act sets out the general duties which employers have towards their employees and members of the public, and employees have to themselves and to others.

In 1992 six proposals from the European Commission were adopted as domestic law in the UK.

One of the pieces of Legislation was The Management of Health and Safety at Work Regulations 1992 (updated in 1999). The Management of Health and Safety at Work Regulations generally are more explicit on what employers and employees are required to do to manage Health and Safety under the Act.

A Risk Assessment is fundamental to demonstration of compliance with the Regulations.

We were requested to visit a site following an incident with a lift. The lift had developed a fault and this resulted in the lift stopping out of floor level, creating a tripping or fall hazard. The engineer had performed some checks, fitted a new part and was checking the lift to ensure that the fault had been corrected. During the initial check the lift went to the bottom floor served and stopped out of floor level, the engineer went up to the upper floor using the adjacent lift to interrogate the controller to see what may have occurred. During the time that the engineer was travelling to the top floor a passenger operated the landing call push and the faulty lift opened its doors in response to the call and the passenger fell into the lift and sustained injuries as a consequence.

The client was advised and the lift was isolated. During our investigation we requested whether Risk Assessments and Method Statements were available and requested to see copies. The engineer had copies on his hand held terminal. As a result paper copies were made available.

During our investigation we checked the Method Statements and it was evident that the Method Statements were inadequate. There are a pair of lifts grouped together on this site and they have a single landing call push, when the landing call push is operated the lift that can respond quickest is allocated the call. During the tests being carried out the faulty lift had not been isolated from the landing call system and a barrier had not been placed across the entrance to prevent access during the engineer’s diagnostic procedures and corrective works.

The Generic Method Statements produced by the Health and Safety Department as a consequence of a Generic Risk Assessment being undertaken did not provide sufficient detail to prevent the incident occurring.

It was also evident that no site specific Risk Assessment had taken place. This is a fundamental requirement when undertaking any work.

The lack of understanding on how to comply with Legislation and the lack of suitable procedures quite clearly contributed to the incident. It also became apparent that the Risk Assessments and Method Statements had not been proof checked and tested on site to ensure that they were suitable for the tasks that they should have covered as other shortcomings were identified.


The Operation and Maintenance Manual

The operation and maintenance manual (O & M Manual) contains important information on how to properly and safely maintain your lift, escalator and moving walk. It should be readily available for anyone involved in inspecting, maintaining or repairing your vertical transportation equipment.

However how many times has the inspector, repair engineer or maintenance engineer asked to see the manual?  The simple answer is never.

This is quite disturbing as the manual provides the guidance to ensure that the equipment is maintained and repaired so that it is safe, reliable and meets or exceeds its life expectancy.

Quite often the company providing the maintenance service has recommended the number of visits they will carry out based on their own standards documents. The O&M manual will provide the frequency of visits and the works that need to be completed at each visit.

When you take your car in for a service a strict routine is followed based on the service type, this should be no different when a lift is maintained but unfortunately it is.

BS EN 13015 Maintenance for lifts and escalators — Rules for maintenance instructions states in section 3:

The instructions for maintenance of an installation according to the Lifts Directive shall be provided by the installer, as defined in 3.5, after completion of the installation, as a result of a risk assessment.

The instructions for maintenance of the safety components of lifts shall be provided by the manufacturer to the
installer as respectively defined in 3.4 and 3.5.

The instructions for maintenance of an installation according to the Machinery Directive shall be provided by the manufacturer, as defined in 3.4, when placed on the market, and be the result of a risk assessment.

In order that the aim of the maintenance instructions can be achieved, they shall be formulated so that they can be clearly and easily understood by competent maintenance persons.

The operation and maintenance manual usually sits gathering dust on a shelf or hidden away in a cupboard. A lot of effort goes into the production of these valuable documents but unfortunately the vital information is very rarely used. WHY?

How will you assess what needs to be done?

The current Standards EN81 part 1 and 2 have represented the standard for lift installations and been the best point of reference for property and facilities managers to ensure that lift equipment is appropriate and safe for tenants and residents. When the new standards are implemented what can we expect from these new codes?

Certainly these documents will be no less exacting in terms of the safety requirements that are set for lifts. In fact the safety of lifts will continue to be of the highest priority, ensuring the wellbeing of residents and maintenance personnel alike. However with improved safety requirements is likely to come higher cost and it is an unfortunate reality that the capital costs of new and replacement lifts are likely to rise and this will be an additional burden for landlords and maintenance professionals unless suitable strategies are put in place.

Modernise or Replace

Whenever lifts reach the end of their serviceable life, there is a decision to be made – do we modernise or replace?

Modernisation has always represented the lesser impact on building users. Machines and vital safety equipment can be replaced, often at a reduced impact to residents and tenants if smart sequencing is used, but it has often proved the more expensive option.  A full replacement with a new lift, although it’s implementation is less desirable for residents, has often proved the more cost effective option.

But now we will need to address this assumption and look again at what is right in each circumstance.

Looking to 2017 and beyond, a strategy for lift assets is required to ensure expenditure is correctly applied to maximise the lift and serviceability of the whole of the lift portfolio.

Strategy based understanding

Lifts are inspected all the time, by landlords; by insurance companies; by maintenance engineers. Why is it then that so few organisations hold registers of the vital data that is needed to make appropriate decisions on efficient lift expenditure?

If property managers are not confident that they have a suitable asset register to facilitate decision making, it is recommended that they undertake a review of their lift portfolio by commissioning an auditing project.

An appropriate audit of a lift portfolio will  examine existing equipment and its maintenance standards along with vital aspects such as existing modifications or DDA compliance.

Once this asset register is available it will help in the planning and implementation of a lift strategy for 2017 and beyond. It will aid in the prioritisation of works and help to target expenditure to where it will improve tenant satisfaction and reduce future costs.

The changes of 2017 will certainly be navigated best by those who are prepared.




Preparing for the biggest change to lift standards in twenty years…

Many of you will have attended one of the seminars we held throughout this year and will now be aware that 2017 will see the most comprehensive revision to lift standards for nearly 20 years.

Implementation of the new standards (EN 81-20/50) will greatly improve the level of safety and will also provide an opportunity for a greater harmonisation of the codes and standards around the world. However the  application of EN 81-20/50 may require design changes or possibly complete re-designs to ensure that lift equipment meets the requirements of the new standards. So, as we come closer to the withdrawal of EN 81-1/2 it is important to be prepared for the introduction of new products which should comply with EN 81-20/50 .

Indeed, we have been talking with our clients well in advance of the 2017 date. For example, in 2013 we engaged with Wheatley Group (One of the UK’s largest housing, care and property management companies) to discuss the design of new lifts for their residential tower blocks in Glasgow.  In 2014, knowing that EN81-20 & 50 were imminent, we produced a performance based specification around the new standard so that fully compliant lifts would be procured following the Standards being published. We also worked with major third party suppliers to ensure their products could comply fully when installed. Eight lifts have now been manufactured and site works will commence in January 2016.

Escalators & Moving Walks, an accident waiting to happen?

In recent times there have been more and more reports of incidents on both escalators and moving walks. It could be argued that this may be due to the large numbers of units that have been installed over the last few years, however there may also be an underlying reason.

Whilst working on projects we have noticed that during the construction phase scaffold and mobile elevated working platforms (MEWPS) have been placed on the steps of escalators and pallets on moving walks and the tread plates. The steps, pallets and tread plates are not suitable for the point loads that scaffold and MEWPS apply. This could result in step or pallet pile ups as the steps and pallets could be weakened or fractured and the tread plate may be dislodged or not sit properly in its seating.

Only last week, whilst inspecting lifts, escalators and moving walks we noticed that a mobile scaffold tower had been placed on the tread plate. When we asked for the scaffold to be removed it transpired that it had not only bent the tread plate but also punctured it.

During the construction phase or future works it is imperative that the steps, pallets and tread plates on escalators and moving walks are not used to support scaffolds or MEWPS. The problem may not manifest itself until the unit is in service, resulting in an unnecessary accident and expensive repairs.

Changes to Safety Regs and the implications for Lift Owners

The Construction (Design and Management) Regulations 2015 were passed by parliament on 29th January and come into force on 6th April 2015. These replace the previous 2007 CDM Regulations.

There are significant changes with implications for lift owners and the lift industry, particularly in terms of maintenance, modernisation and new installations in existing lift shafts.

•           The regulations now apply to domestic clients and private dwellings!
•           The CDM Co-ordinator role is removed.
•           The Principal Designer role is introduced. Designers must be competent and experienced in   the industry relevant to the works.
•           Fewer projects will be notifiable to the HSE. Only jobs on major construction sites employing more than 20 workers and lasting more than 30 days or large scale modernisation projects lasting more than 500 man days will be notifiable. Maintenance contracts on as few as 34 lifts could however be notifiable!
•           All projects including small repairs will however fall under the scope of the regulations (even if they are not notifiable). This will mean that construction phase health and safety plans will be required on a visit by visit basis. If lift maintenance is carried out by a single contractor there is no need for a Principal Contractor or a Principal Designer. If however a lift contractor were to subcontract a re-rope or gate repair or any other works to a different Contractor the Client would have to appoint a Principal Designer and Principal Contractor.
•           The Client has additional responsibilities to make appointments and arrangements to manage a project, provide pre-construction information and assist the Principal Designer and Principal Contractor with their duties. Unless a Client appoints a Principal Designer he may take on the designer’s responsibilities and may not have the necessary competence to do so.
•           Existing projects which have started the construction phase before 6th April and will complete before 6th October 2015 can continue to be run as before.
•           For existing projects which start the construction phase after 6th April and will complete after the 6th October 2015 the Client must appoint a Principal Designer.

Noisy contactor – replace or repair?

Lift Control Panels vary considerably depending on the age, design, required duty and available technology. Over the years the systems have moved to Solid State Technology,  Microprocessor Control, and the wider use of Printed Circuit Boards and Software, however there is still a need to utilise Relays and Contactors for some functions.

Over time and use, Relays and Contactors will fail and require replacement. The failure may involve worn contact surfaces causing high resistance or the activation coil may fail due to age or overcurrent. An initial sign of the Relay or Contactor failing is an excessive “buzzing” noise. The buzzing is caused by the electro magnet faces not coming together properly, this may be caused by dirt on the faces or wear. When this happens the coil draws more current and premature failure is usually the result.

It is possible to eliminate the buzzing by cleaning out the dirt, however depending on the age and design, it is usually best to replace the component as it is not certain that it won’t just start up again.
Depending on your contract type, the cost of replacement may or may not be included, if not be careful as to how much you are charged.