Surface LED series SFL-UV

The common technical data give a uniformity of typically more than 90 % at a distance of 10 mm from the emitting window, with a standard deviation of 5 %. The area also stays uniformly irradiated at a greater distance - the photograph shows an SFL-UV-L ECO flood lamp with 385 nm UV LEDs.

These are orientation values: they depend on the emitting area, the wavelength, the power level and the distance. The greater the distance, the larger the irradiated area and the lower the irradiance.

The LedControl can be controlled through the programming interface on the rear - USB, RS485 or RS232 as required. Communication uses ASCII, here with "switch on" as an example:

• the control sends: LOnOff:1!
• the LedControl answers: LOnOff: 1 (CRC-16)

Every channel can be controlled individually. The LedControl only sends when the control asks for it, and any number of LedControl units can be cascaded.

Through the PLC interface option the LED power (0 to 10 V), switching on and off (trigger input 24 V) and the status (trigger output 24 V) are set and queried. With its robust signals this option suits simple integration into a plant.

Control uses short ASCII commands. A selection:

If the emitter is supplied with a programming interface, remote example software for testing straight away is included. The test and control software shows the channels with intensity and status, switches them individually, sets timers and presets and logs the communication with the device.

To make machines safe and to meet the requirements of the machinery directive 2006/42/EC, safety functions are needed in the controls. Usually the required performance level PLr is determined for every safety function. This is where the first difficulty with UV installations begins: the severity of the injury, the frequency and duration of exposure and the avoidance of the UV hazard have to be determined.

In the short term, UV exposure of the skin leads to erythema, elastosis and skin cancer; exposure of the eye can lead to photokeratitis, conjunctivitis and cataractogenesis. Skin cancer is a severe and usually irreversible injury.

Directive 2006/25/EC on artificial optical radiation permits regular exposure up to a daily exposure limit of 30 J/m². The severity of the injury can therefore be reduced through the duration and the intensity of the exposure without having to achieve absolute zero exposure: if the limit is observed, healthy adults can be expected to be exposed repeatedly without acute harmful effects. In the event of a fault, a short exposure may cause a reversible injury such as a slight erythema. The boundary is not reliable, however, and measures and safety functions are needed in every case.

Measurements are possible on existing installations; during the planning phase they are not, or only with additional effort, which is why a higher PLr is often demanded. This is exactly what the LedControl and the PLready option are for - already at the planning stage.

The PLready safety option is suitable up to PL category 4 according to EN ISO 13849-1 and SIL 3 according to EN 62061, provided that cross-faults in the control of the LED module and in the sensor circuit can be excluded.

It works with a safety extra-low voltage (SELV) of 48 VDC that is safely separated by an external circuit and can switch the LED modules off completely in the event of a fault.

The optional shutdown for the performance level separates the LED modules through an external contact:

A two-channel safety door monitoring with automatic start is shown in the following example. Compared with simply separating the DC voltages, the advantage is the monitoring of the external contactors. The example is suitable up to category 4, PL e (EN ISO 13849-1) or SIL 3 (EN 62061), provided that cross-faults in the control of the actuator and in the sensor circuit can be excluded.

The device emits UV-A and blue light. UV radiation is invisible. Any visible light is only luminescence excited by the radiation; it is usually much weaker than the exciting UV radiation. The irradiance of the device is several hundred times stronger than that of sunlight.

UV-A radiation can cause cataracts in the lens of the eye and inflammation of the retina. Always wear suitable UV protective goggles when operating the device. UV-A also causes skin discolouration and skin ageing; use suitable clothing, gloves and further personal protective equipment - depending on the irradiation dose.

The devices are designed and classified according to DIN EN 62471:2009-03 "Photobiological safety of lamps and lamp systems"; the SFL falls into risk group 3. Do not look into the LED and do not expose the skin to the UV radiation permanently.

We are glad to support you in setting up UV workplaces and with the risk assessment according to DIN EN 14255:2005.

The sizes M, L and XL differ in the irradiated area.

Scope of delivery: the SFL-UV module, the LedControl, a cable of 3 m and the manual; when the optical feedback option is ordered, also a UV sensor with a factory calibration certificate. Please state the wavelength and the options with your order.

The order number is made up of the version and the wavelength - for the SFL-UV-M ECO at 365 nm therefore 860616-M-365 nm. The peak wavelength lies within ± 5 nm.

The HO version (high output) delivers the higher irradiance.

The emitters are operated through a LedControl - S for mains operation, DC for operation at 24 V.

The interfaces and the PLready safety option are ordered together with the control unit.

* including the PLC interface option.

The connecting cable is 3 m long, on request up to 10 m; further metres are charged individually.

The UV protective goggles protect the eyes and the surroundings from stray radiation; the emitters are classified in risk group 3 according to DIN EN 62471.

The irradiance can be measured with the RMD radiometer and the UVA+ sensor; the sensor is also used to calibrate the optical feedback.