WO2018109261A1

WO2018109261A1 - Lighting system

Info

Publication number: WO2018109261A1
Application number: PCT/FI2017/000004
Authority: WO
Inventors: Timo Lamberg
Original assignee: El & Site Oy
Priority date: 2016-12-15
Filing date: 2017-03-03
Publication date: 2018-06-21
Also published as: FI11665U1

Abstract

The present invention is related to lighting in work sites, especially to lighting systems used in work sites, and their structures. A work site lighting system according to the invention comprises at least a cable system (130, 120) that comprises a plurality of cables (130) having quick-connect fittings and a sheath with a high visibility colour and T-pieces (120), and one or more work site lights (110), which comprises one or more light emitting diodes and a driver unit for supplying current to said light emitting diodes and at least one quick-connect fitting for connection of a cable of the cable system.

Description

Lighting system

The present invention is related to lighting in work sites, especially to lighting systems used in work sites, and their structures.

Many different kinds of lighting systems are currently in use in work sites. For example, spot lights and other non-fixed lights are commonly used at small work sites or individual work locations, lights which are directly connected to 230 volts mains voltage. This kind of lights are in very common use, since their use is very easy and simple and their connection or removal does not require an authorized electrician. A negative side in the use of this kind of lights is the danger of overload, since these kinds of lights are typically connected to the mains network of the worksite, namely the one to which also the tools used at the worksite are connected to. Then, if an overload situation occurs for example due to a tool, and the fuse of the particular circuit is blown, also all lights connected to that circuit go dark, which is both troublesome and can be dangerous, if all lights at the worksite go dark.

In order to avoid overload situations, specific circuits for lighting purposes only are often installed at larger worksites. Machines and tools are therefore not connected to this mains circuit dedicated to lighting, whereby lighting does not suffer in a possible overload situation. In largest worksites this kind of separate mains circuit is typically built as a fixed circuit, since use of extension lead constructions is always a safety risk. Typically, fluorescent lights are used in this kind of systems, whereby a reasonably good light intensity is achieved with a reasonably small use of current. This kind of separate 230 volt lighting circuits are reliable and these can be used to build a sufficiently bright and reliable lighting to all areas of the worksite. A drawback in such a 230 volt system is that building and removal of such a system needs to be performed by an authorized electrician. A normal construction worker is not allowed to do electrical installations. This complicates planning of the worksite and increases costs.

Different embodiments of the invention are illustrated in the figures, where figure 1 illustrates a lighting system according to an embodiment of the invention. In an advantageous embodiment of the invention the lighting system is implemented using led-based lights. In this embodiment the lights are supplied via a transformer unit, which transforms the normal mains voltage of 230 volts alternating current to low-voltage alternating or direct current. Advantageously, this low voltage is roughly 48 volts low voltage. In this embodiment the lights are connected to the transformer unit using cables having two conductors and quick-connect fittings. This kind of cables can be connected in series using continuation pieces or T-pieces. Supply voltage can be taken out to a single light from a thus formed trunk line using a T-piece. Implementing a lighting system using cabling implemented using quick-connect fittings is beneficial, since this kind of system is quick to connect and the connection can be made by any work site worker, without need for a qualified electrician.

Figure 1 illustrates an advantageous embodiment of the invention. Figure 1 shows a transformer unit 100, which has three outputs 101 for lighting systems. Figure 1 shows cables 130 connected to form a trunk line 131 and connected to one output 101 . T-piece 120 has been used to implement intermediate outputs to lights 1 10. Figure 1 illustrates also such a type of light 1 10, which has in addition to supply voltage input 1 1 1 also a supply voltage output 1 12, to which a second light 1 10 can be connected to with a cable 130.

Figure 1 shows also a second trunk line 131 connected to the transformer unit 100.

Next we discuss different alternatives of light 1 10 in different embodiments of the invention. The light 1 10 can comprise in addition to a supply voltage input also a supply voltage output, which enables connection of lights into a chain. In another embodiment of the invention the light can have instead of a quick-connect fitting for supply voltage a connection cable having a quick- connect fitting at the end. In different embodiments of the invention the light 1 10 is implemented based on LEDs i.e. light emitting diodes. In addition to LEDs, the light 1 10 comprises a driver circuit needed for supplying the LEDs with current. This kind of driver circuit can be implemented so that it can be supplied with either direct or alternating voltages, i.e. this kind of driver circuit can be implemented in such a way that the polarity of the supply voltage is irrelevant. This makes connection of the lighting system easier and reduces probabilities of faults.

In the following alternatives associated with the transformer unit 100 in different embodiments of the invention are described. The transformer unit 100 can have one or more outputs for supplying electrical power to the lights via cables. In an advantageous embodiment of the invention the power supply has a timer control, which turns the lights on and off automatically at desired times. Such a transformer unit can be arranged to turn the lights on when work time starts and turn the lights off when work time ends. Advantageously in such an embodiment the transformer unit also comprises means, through which the user can easily arrange for additional time for the lights to be on. This kind of means can be implemented for example using a push button, pressing of which makes the lights stay on for a predetermined time more, for example half an hour, one hour, or two hours. Further, advantageously, this kind of timer control is in use separately for each output of the transformer unit.

In an advantageous embodiment the transformer unit has indication for overload of the transformer unit. This indication can be for example a signal light or a buzzer or another similar indication means. If too many lights are connected to an output of the transformer unit, this indication means or the transformer unit signals this using the indication means, for example by turning an overload signal light on. Thereby the transformer unit advantageously also goes into a protection state, in which it supplies into the particular output either no electrical power or less than maximium power, in order for the transformer unit not to be damaged due to the overload. Advantageous the power supply sorry transformer unit returns to normal state, when lights are disconnected from the overloaded output. This kind of automatic indication of overload state and recovery from overload state makes it easier to build and change a lighting system, when this tranformer unit directly indicates to the user and builder of the system that the maximum load has been exceeded. Advantageously this kind of overload indicator is at every output of the transformer unit, whereby it is clear to the builder of the lighting system, in which of the lighting trunk lines has the overload situation happened. In the following possible features of cables 130 of the lighting system in different embodiments of the invention are described. Advantageously the cables and outputs of the system have female pins at those ends, where supply voltage is present. Thereby the output of the transformer unit has female pins and a cable, that is to be connected to such an output, has male pins. The other end of this cable also have female pins, so that when the cable is connected to the transformer unit and has a voltage present, risk of short circuits and wrong connections is small, since the powered pins are female pins, whereby the danger of short circuits presented by foreign objects is small. In a low voltage system the cables 130 have been implemented as two conductor cables, most advantageously as a twisted pair cable with a sheath. Advantageously cables 130 have been implemented in different colours than usual 230 volts mains voltage cables, such as in a high visibility colour, for example in yellow. This has the advantage, that cables and connections of the lighting system implemented in high visibility colour can be clearly distinguished from other connections, which further reduces the number and possibility for wrong connections, and increases the durability and resiliency of the system. Advantageously the quick-connect fittings of the cables are protected against water and dust, which further improves the reliability and safety of the system.

In an advantageous embodiment of the invention the lighting system according to the invention comprises also a moisture and dust protected plug, which can close an open output in a continuation or a branch piece, connection cable, or light. This further protects the system for dust or moisture and thereby improves the safety and reliability of the system.

In an advantageous embodiment of the invention the lighting system is arranged to directly use 230 volts alternating voltage. In this embodiment lights 1 10 and specifically the driver circuit in them is arranged to receive and use 230 volts alternating voltage. In this kind of embodiment the cables 130 and T-pieces 120 have advantageously three conductors. Of these three conductors, one is a protective earth and two form a power transmitting circuit. In this kind of embodiments the quick-connect fittings are advantageously different from those in low-voltage lighting systems and on the other hand also different from those in the standard 230 volt systems, i.e. different than the usual "Type F" or "CEE 7/4" plug. This is in order to avoid mixing of a low voltage system and its components in a 230 volts system, and also in order to avoid connection of other devices such as work machines or similar to such a 230 volts system.

A lighting system accoding to the invention has several benefits. For example, due to special connectors normal mains powered devices or work machines cannot be connected to the lighting cables or lights of a system according to the invention. Thereby overload of an electrical network used for lighting due to work machines can be avoided, increasing reliability of the lighting. Along with increased reliability of lighting also work safety in the work site is improved. In a system according to the invention it is both possible and economically worthwhile to implement cables 130 as cables protected by a sheath, whereby the cables are able to withstand several uses, i.e. they can be connected and disconnected a plurality of times. Such a cable is therefore also more durable and safe than cables implemented via connection of single leads using screw connections or other simple quick connectors. If the starting point of design and implementation of a lighting system of a work site is single use, less well protected and mechanically more easily damaged leads are often used. This in turn can in work site conditions easier lead to a fault, which can lead to reduction in lighting and danger situations. This kind of troubles and instances of danger can be avoided by using a system according to the invention and sturdy cables 130. In addition, when the cables 130 have been implemented to be able to withstand several times of use, the lighting system according to the invention is very well suited to be used in rental business. Traditionally 230 volt lighting systems using fluorescent lights and implemented using individual wires, suit a rental-type business very badly, since fluorescent lights are very susceptible to getting dirty during installation, use, and removal. A system according to the invention therefore enhances business especially in rental activity.

In the following embodiments of the invention according to an aspect of the invention are described. In a first embodiment the work site lighting system comprises at least

- a cable system (130, 120) that comprises a plurality of cables (130) having quick-connect fittings and a sheath with a high visibility colour and T-pieces (120), and

- one or more work site lights (1 10), which comprises one or more light emitting diodes and a driver unit for supplying current to said light emitting diodes and at least one quick-connect fitting for connection of a cable of the cable system.

In a second embodiment of this aspect the work site lighting system further comprises at least a transformer unit (100) for producing a low voltage to work site lights, whereby said low voltage is advantageously roughly 48 volts, and in addition, said connection cables (130) have two conductors.

In a third embodiment of this aspect the transformer unit has an overload indicator. In a fourth embodiment of this aspect the transformer unit comprises at least one timer device.

In a fifth embodiment of this aspect said transformer unit comprises at least three low voltage outputs (101 ). In the previous, the invention has been described with reference to certain advantageous embodiments of it, but it is clear to a man skilled in the art that the invention can be varied in many different ways according to the inventive concept defined by the attached patent claims.

Claims

1. Work site lighting system, characterized in that it comprises at least

- a cable system (130, 120) that comprises a plurality of cables (130) having quick-connect fittings and a sheath with a high visibility colour and T-pieces (120), and - one or more work site lights (110), which comprises one or more light emitting diodes and a driver unit for supplying current to said light emitting diodes and at least one quick-connect fitting for connection of a cable of the cable system.

2. A work site lighting system according to claim 1 , characterized in that it further comprises at least a transformer unit (100) for producing a low voltage to work site lights, whereby said low voltage is advantageously roughly 48 volts, and in that, that said connection cables (130) have two conductors.

3. A work site lighting system according to claim 2, characterized in that the transformer unit has an overload indicator.

4. A work site lighting system according to claim 2, characterized in that the transformer unit comprises at least one timer device.

5. A work site lighting system according to claim 2, characterized in that said transformer unit comprises at least three low voltage outputs (101).