Siena LED Grow Light 40W

The Siena LED Grow Light from IHS has been designed for easy installation in vertical farms, rack systems and bench lighting. The lightweight design incorporates an integrated heatsink for optimal thermal management. Additionally, the inline connectors allow for easy connection to a LED driver. The spectral output from the Siena LED Grow Light is broad spectrum including hyper and far red. Plants are subjected to multiple wavelengths across the spectrum. Hyper red light is beneficial for plants as this specific wavelength is absorbed by the plant’s phytochrome pigment.

The Siena LED Grow Light mix of LEDs has been developed to increase and improve overall plant growth. The spectra has been designed to complement a growing environment where there is already available daylight.

With a built-in lens providing a 120 degree coverage, large areas of target plants can be illuminated with a single Siena LED Grow Light. With a 100-240VAC mains input that can be installed by any standard electrician, no complicated wiring or installation processes are required. With brackets included, and a weight of only 0.8kg, installation is very simple in any application. Each LED Grow Light is fitted with an IP65 connector which allows for easy connection.

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Product Code: SIENA-40W-UK Categories: ,


  • Horticultural lighting

  • Environmental chambers

  • Propagators

  • Indoor farming

  • Polytunnels

  • Small greenhouses

  • Indoor home growing

  • Schools and universities

  • Research institutes




System efficacy

1.9 umol/J @ 220Vac

PPF Output

76 umol/s

Input Power

100-277Vac 50-60Hz

Current Range

0.40A @ 100V , 0.14A @ 277Vac

Isolation Class

Class I

Heat BTU Generated


Power Factor



1-10V 0-10V optional

Beam angle





Brackets and screws

Type of Protection

IP65 (dust and watertight)






5 years


1116 x 55.8 x 35.1mm

Operating Temperature

0°C to 40°C

Storage Temperature

-40°C to 70°C


Supplied with each Siena LED Grow Light are the following accessories.

Mounting brackets x2 (included with each light) LED driver with 1-10V dimming (sold separately)

LED Driver

Lamps per Driver













Spectral Characteristics Calculations Explained

Below you will find specific photometric information for SIENA-40W-UK. This includes:

  • Spectral power
  • Spectral output
  • Spectral distribution patterns.

These three sets of spectral measurements have been obtained by testing a standard production unit, rather than a ‘special’ engineering unit. All readings were carried out in IHS’s in-house test facility in order to provide real life values that you can use in your own calculations.

The SIENA-40W-UK was suspended using a single chain and powered according to our Siena installation manual.

The height of the unit was then varied so the front face of SIENA-40W-UK, that is at lens level, was measured to the sensor level at varying increments: 300mm and 450mm.

The unit was powered and left switched on for 2 hours before readings were taken to ensure thermal stability within the product had been achieved. Ambient temperature stood at approximately 20°C, whereby the average heatsink temperature increase was noted to be 50°C after stabilisation.

The spectral output graph below shows the percentage in flux for each wavelength. For example if 660nm shows 90% and 455nm shows 10%, then you know the ratio of 600nm to 455nm is 2:1.

The spectral power illustration below represents the umol/m2/s reading taken at the central point at each of the varying heights. This value corresponds to a reading area of 750mm2.

The spectral distribution patterns provided below for each of the varying heights show the total umol/m2/s readings taken at 150mm intervals. If you look at the central value, the number either side depicts the umol/m2/s reading 150mm further out from the centre.

So a 0.45m2 area is shown on the chart as 3×3 squares.

Spectral Output

Spectral Power

Spectral Power and Distribution Patterns

Technical Drawing

Important Precautions

  • The LED module when powered up, are very bright. Thus it is advised that you do not look directly at them. Turn the LED module away from you and do not shine into the eyes of others.

  • LED modules, when operated, can reach high temperatures thus there is a risk of injury if they are touched.

  • DO NOT TOUCH or PUSH on the LED as this can cause irreparable damage.


Safety Information

  • The LED module itself and all its components must not be mechanically stressed.

  • Assembly must not damage or destroy conducting paths on the circuit board.

  • To avoid mechanical damage to the connecting cables, the boards should be attached securely to the intended substrate. Heavy vibration should be avoided.

  • Observe correct polarity! Depending on the product, incorrect polarity will lead to emission of red or no light. The module can be destroyed!

  • Pay attention to standard ESD precautions when installing the LED module.

  • Damage by corrosion will not be accepted as a materials defect claim. It is the user’s responsibility to provide suitable protection against corrosive agents such as moisture and condensation and other harmful elements.

  • For outdoor usage, a housing is definitely required to protect the board against environmental influences. The design of the housing must correspond to the IP standards in the application. It is also the responsibility of the user to ensure any housings or modifications keep the Tc junction temperature to within stated ranges.

  • To also ease the luminaire/installation approval, electronic control gear for LED or LED modules should carry the CE mark and be ENEC certified. In Europe the declarations of conformity must include the following standards: CE: EC 61374-2-13, EN 55015, IEC 61547 and IEC 61000-3-2 – ENEC: 61374-2-13 and IEC/EN 62384.

  • The evaluation of eye safety occurs according to the standard IEC 62471:2006 (“photobiological safety of lamps and lamp systems”). Within the risk grouping system of this CIE standard, the LED specified in this data sheet falls into the class “moderate risk” (exposure time 0.25s). Under real circumstances (for exposure time, eye pupils, observation distance), it is assumed that no endangerment to the eye exists from these devices. As a matter of principle, however, it should be mentioned that intense light sources have a high secondary exposure potential due to their blinding effect. As is also true when viewing other bright light sources (e.g. headlights), temporary reduction in visual acuity and afterimages can occur, leading to irritation, annoyance, visual impairment and even accidents, depending on the situation.

Installation and Mounting

For details about the installation and mounting of the Siena LED Grow Lights please refer to our documentation.

Siena LED Grow Light – Installation Manual

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