UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G1 of 8

Travellator

A travellator differs from an escalator in being either horizontal or having a very small

slope of not exceeding 15 o. This makes it unnecessary for it to form steps and

passengers are conveyed on a continuous platform. The upper surface of the platform

must have grooves parallel to the direction of motion which mesh with the combplates.

In other respects a travellator or moving walkway is designed in exactly the same way

as an escalator.

Travellators are used at air terminals, railway stations and shopping centres; they can

be used by infirm, or by people with wheeled baskets or perambulators.

Travellators are set in motion by a key-operated switch, and safety measures include

an emergency stop push button, fitted at each end of the travellator. A powerful

electo-mechanical brake is fitted to the driving mechanism, which stops the travellator

in the event of a fault.

Key parameters:-

Typical inclination – 0o, 10o,11o, 12o ,15o; Typical step width – 800mm, 1000mm;

Typical pit depth – 1150mm;

Typical balustrade height – 900mm.

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G2 of 8

Paternosters

Whilst paternosters are a type of lift they have similarities with escalators. A

paternoster is a lift which has a series of small cars running continuously in a closed

loop.

(Adopted from The Vertical Transportation Handbook edited by George R. Strakosch)

The cars are open at the front and move slowly enough for people to step in and out of

them whilst they are in motion, just as they step on and off an escalator. In fact a

paternoster can perhaps be thought of a vertical escalator. To make it safe for people

to step on and off whilst the cars are in motion the speed must be less than 0.3m/s.

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G3 of 8

(Adopted from The Vertical Transportation Handbook edited by George R. Strakosch)

The cars are constructed in the same way as ordinary lift cars but do not have doors

and car sizes are limited to not more than one passenger each. In practice this means

that the cars are less than 1m x 1m in plan.

Since the cars move in a continuous loop they provide their own counterweight. Rigid

guides are provided for the cars which have shoes similar to those of ordinary lift cars.

Although they have advantages, paternosters are not used very often. They take up

rather less space than escalators but have a lower carrying capacity.

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G4 of 8

Design consideration

→ Refer to ISO 4190 for guidelines of dimensions of lift cars, lift shafts, lift motor

room, etc.

→ Refer to BS EN 81 for lift safety requirements

→ Refer to Hong Kong Fire Services Department Code of Practice regarding

fireman’s lifts, e.g. fireman’s switch, secondary power supply for lifts, fireman’s

lifts to reach top floor from the designated point of entry within 60 seconds

inclusive of lift door closing and opening time.

→ Care must be exercised regarding battery lighting and alarm, emergency

inspection doors not more than 11m apart in lift shafts (Code of Practice on the

Design and Construction of Buildings and Building Works for the Installation

and Safe Use of Lifts and Escalators), machine room artificial ventilation,

machine room lighting level (not less than 200 lux)

→ Electrical power supply and heat dissipation of lift equipment in lift motor room

to be obtained from lift contractor

→ Other services installation not to be routed through lift shafts and lift machine

rooms unless they form part of the lift installation.

→ Watch out for minimum contract load / car platform size as stipulated in

ISO4190.

→ Watch out for the need of EMC filter in power supply.

Before modernization After modernization

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G5 of 8

Lift lobby arrangement

Normally decided by architect, not building services engineers, but remember to avoid

arranging more than 3 lifts serving the same zone in a row (take a look at Hopewell

Centre!)

Unacceptable lobby arrangement for six lifts

Preferred lobby arrangement for 6 lifts

A lift machine room

(Adopted from HALL, F.E. Building Services & Equipment)

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G6 of 8

Escalator Landing Buffer area

(Adopted from The Vertical Transportation Handbook edited by George R. Strakosch)

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G7 of 8

Some general data on lift power requirement / heat dissipation

The data given below serves as an indication only. Actual data may vary with different

makes of lifts.

Contract

load, kg

Contract

speed, m/s

Full load

current, A

Peak

starting

current, A

(*)

Peak

duration, s

Heat

rejection,

kW (#)

1000 0.63 26 82 1.5 2.7

900 1.00 26 82 1.5 3.2

1000 1.60 30 107 2.0 4.9

1250 1.60 50 138 2.0 6.2

1350 2.50 50 138 3.0 7.9

1500 1.60 60 176 2.0 7.4

1500 2.50 60 176 3.0 8.8

(*) Non-soft-start type

(#) Rule of thumb:

Geared machine including most single speed and 2-speed AC machines – 30 to

60% of motor kW

Gearless machine including most DC machines and VVVF machines – 20 to

30% motor kW.

Hydraulic machine – about 20% of motor kW

UNIVERSITY OF HONG KONG M.Sc.(Eng) in building services engineering

MEBS6000 2010 Utilities Services

K.F. Chan (Mr.) G of G Page G8 of 8

Periodic examination and maintenance of lifts and escalators

The following periodic examination and maintenance is required by law in Hong

Kong:

The owner of every lift and escalator shall cause the lift or escalator …. to be

inspected, cleaned, oiled and adjusted by a registered lift contractor or registered

escalator contractor, at intervals not exceeding one month.

The owner shall at intervals not exceeding 12 months cause the lift to be

thoroughly examined by a registered lift engineer (Form 11).

� Instead of keeping a certificate, the owner of the lifts / escalators is required

to keep a logbook and to produce it for inspection on demand by the Director

of Electrical & Mechanical Services Department.

� The owner shall cause the registered contractor or registered engineer to

record details of any maintenance work carried out.

The owner shall cause the safety equipment to be tested by a registered lift

engineer

� at intervals not exceeding 12 months, by the operation of the safety

equipment without any load;

� at intervals not exceeding 5 years, by the operation of the safety equipment

with full rated load;

� at intervals not exceeding 5 years, by the operation of the overload device of

the safety equipment with a load in the car of the lift weighing between 90%

and 110% of the rated load;

� at intervals not exceeding 5 years, by the operation of the brake when the car

or platform of the lift is travelling in the downward direction at its rated

speed:

∗ with a load weighing 110% (before BS5655: Part 1),

∗ with a load weighing 125% in all other cases.