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PQS 1 PAR Quantum Sensor

PQS 1 PAR Quantum Sensor

Quick Overview

The PQS 1 measures the Photosynthetically Active Radiation (PAR) from the Sun, or artificial light sources. The PAR light is absorbed by chlorophyll in plants and crops for photosynthesis. It is a key parameter for agriculture, horticulture and greenhouse automation. The PQS 1 offers a response with an excellent match to the ideal PAR response. The rugged construction allows the sensor to be used under all weather conditions and is well protected from harsh weather conditions and from exposure to pesticides and fertilisers. Spectral range 400 to 700nm. The PQS 1 is ideal for permanent, or portable field testing, for both indoor and outdoor agricultural, horticultural and greenhouse environments.
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Light from the Sun plays a crucial role in plant and crop growth. Plants absorb light (mostly by chlorophyll) to drive the photosynthesis process whereby Carbon Dioxide and water are photo-chemically converted into Glucose and Oxygen. Light which a plant can use for this process is called Photosythetically Active Radiation (PAR). The actual response differs depending on the plant or crop but a measurement of PAR can be used as a means of evaluating agricultural investment potential.

The PQS1’s sensitivity has been optimized to provide reliable and accurate measurements regardless of the PAR source, either from natural light or artificial light sources, eg. high pressure sodium lamps, making the PQS1 instrument perfect for studies of crop growth in greenhouses or out in the field.


Spectral range: 400 to 700nm ± 4nm
Sensitivity: 4 to 10µV/µmol/m²·s
Response time (95%): < 1µs
Non-linearity: < 1%
Temperature dependence: < -0.12%/ ºC
Sensitivity change per year: < 2%
Directional response (up to 80°): <30µmol/m²·s
Impedance: 240Ω
Field of view: 180°
Operating temperature: -30 to +70°C

The mounting flange incorporates a bubble level and adjustment screws, for easy leveling. A threaded hole takes the accessory screw-in mounting rod for fitting to masts and poles. Two PQS1 sensors can easily be bolted back-to-back, and fitted with the mounting rod, to make a simple PAR albedometer. The standard cable length is 5m, with an option of 15m.

The PQS1 can be used with a suitable handheld display logger to provide a suitable test unit for site evaluation on established or proposed agricultural sites

Field Data Logger Options

Meteon is an accurate handheld display unit and data logger suitable for connection to a single PAR Quantum sensor. Its small size, long battery life and universal input make it an ideal tool for many test and field applications. Meteon comes in a carrying case that also has space for the PQS1. The Meteon can store up to 3500 readings with min, max and average values per logging period.

SQ2010 is a multichannel handheld display unit and data logger suitable for up to 8 input channels with universal inputs suitable for mV, V, mA and PT100 or thermocouple inputs. This would allow for a complete field monitoring kit to accept inputs from multiple radiometer, pyranometers, an albedometer, thermocouples for air temperature, etc. The SQ2010 comes in a carrying case and we can supply the other sensors and suitable customised portable carry cases to suit your own requirements.

Availability: Stock Item


Components / Downloads

For further information, technical advice, or a quotation please call or email us. If you are not sure which product you need one of our technical sales advisors will be happy to discuss your application. We also accept company purchase orders by fax or post. Credit card orders can also be placed over the phone for any product.

PQS 1 PAR Quantum Sensor
PQS 1 Quantum Sensor for Photosynthetically Active Radiation. Spectral range 400-700nm, response time 1ss, non-linearity 1%, directional error 3% (at 80 solar zenith angle), sensitivity 4 - 10V/mol/sm, operating temperature -30C to +70C. Photo-diode detector, diffuser and optical interference filter, mV output and standard captive cable of 5m length.
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PQS 1 Quantum Sensor for Photosynthetically Active Radiation. Spectral range 400-700nm, response time 1ss, non-linearity 1%, directional error 3% (at 80 solar zenith angle), sensitivity 4 - 10V/mol/sm, operating temperature -30C to +70C. Photo-diode detector, diffuser and optical interference filter, mV output and standard captive cable of 15m length.
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Mounting Options
Mounting rod for Kipp & Zonen Pyranometer, Pygeometers and Radiometers sensor. The rod screws into the instrument housing to enable the attachment of the above instruments to poles, masts or walls when used in combination with the CMB 1 mounting bracket. The rod has a diameter of 12mm and a length of 300mm. Suitable for use with the SP-Lite 2, CMP series pyranometers, CGR3 and PQS1 sensors.
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CMB 1 Mounting Bracket. This bracket is suitable for various mounting rod sizes, from 12mm to 20mm diameter, and can be secured via u-bolts to masts or poles from 22mm up to 60mm diameter. The bracket can also be secured directly to a wall, or other flat surface.
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Handheld Meteon Irradiance Data Logger
Configured Meteon Irradiance Data Logger with a large 4-digit LCD display for real-time readings in W/m. Logs 3,518 sets of min, max and average values with programmable logging start delay and interval. Single channel differential input, 6.25 to 200mV. Two 4mm input sockets for banana plugs or bare wires. Logger dimension 70 x 146 x 25mm. IP40. Operating temperature -10 to +40 C. Supplied in a tough carrying case together with: 2 x AA batteries, software and manual on a CD-ROM, USB interface cable and space for a radiometer with up to 10m cable. Suitable for all CMP pyranometers, CM 4, PAR Lite, SP Lite2, NR Lite2 and CUV 5. Meteon data logger will be configured to suit the supplied radiometer.
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SQ2010 Data Logger
Squirrel 2010 data logger, 4 differential or 8 single ended channels, suitable for PT100, thermocouple, mV, V and mA inputs, 24bit resolution, memory 14 million readings. 8 digital inputs, 2 pulse inputs, 2 digital alarm outputs, 5v sensor supply @ 50mA (external 8-28V at 100mA when powered), LCD display with keypad (setup via software or 4 button interface). Up to 10Hz logging rate, USB interface, includes SquirrelView Plus software, USB cable, carry case, batteries and plug in UK/US/EUR power supply.
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View FileManual
   Size: (8.21 MB)
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Enclosure Mounted Amplifier
5331A3B programmable transmitter with a 7.2-35vDC power supply. Single channel unit for PT100, thermocouple, Resistance or bi-polar mV input, producing a 2-wire 4-20mA output. 1.5kvAC galvanic isolation. Programmed to suit the connected sensor. Transmitter fitted in weatherproof enclosure with 2 cable glands.
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5114A Programmable Transmitter
Single channel 5114A programmable transmitter. Single channel unit for RTD, TC, mV, linear resistance, mA and V inputs, producing a (0)4-20mA, 0-10vDC output. 3-port 3.75 kVAC galvanic isolation. Can be mounted vertically or horizontally on a DIN rail. Power Supply 21.6 to 253vAC or 19.2 to 300vDC.
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Complete programming and configuration of programmable amplifiers to client specifications. Standard input ranges would be 0-1600Wm² or 0-3200µmol/m²s depending on the attached solar instrument.
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