DCP007 Industrial Photometer

The Kemtrak DCP007 is an easy to operate industrial fiber optic photometer designed to accurately measure the concentration and color of process samples. Measurements are real time and in-line.

The Kemtrak DCP007 uses a long life high performance LED light source with robust industrial grade fiber optics to provide drift and noise-free measurement with very high precision.

A proprietary dual wavelength four channel measurement technique and advanced digital electronics design allows deep absorbance measurement to 5 AU. A range of shorter optical pathlengths allow for deeper absorbance measurements. Automatic compensation for sample turbidity and/or fouling of the optical windows ensures trouble free operation. Maintenance free measurement cells with sapphire windows have no electronics or moving parts making the unit suitable for hazardous area use.
FeaturesTechnical DataApplications
  • Real time in-line measurement
  • Drift and noise-free measurement
  • Down to 5 AU (1 cm OPL), deeper absorbance measurements with shorter pathlengths
  • Zero maintenance measurement cells & fiber optics
  • Long life LED light source that is easy to change
  • Analogue output (0/4-20 mA)
  • Modbus (slave) over TCP/IP & Profibus (optional)
  • Local & web based graphical user interface (TCP/IP)
  • ATEX Exd IIB + H2 T6 IP66 Category II 2 G (optional)

Measuring Principle

The Kemtrak DCP007 photometer measures at two wavelengths. A primary “absorbing” wavelength is used to measure the substance being monitored while a “non absorbing” reference wavelength is used to compensate for turbidity, air bubbles and/or fouling.

Kemtrak industrial UV-VIS-NIR process photometer dual wavelength detection

Fiber optics are used to shine a precisely focused light beam through the process medium and back to a silicon photo-detector. A second photo-detector is used directly on the lamps to compensate for temperature effects and aging. The resulting measurements are very accurate with low drift and long-term calibration stability.

The attenuation of the transmitted light beam caused by light absorbing substances in the process medium is mathematically described by the Beer-Lambert law.


Applying the Beer-Lambert law (below), the concentration of the sample can be calculated.


Kemtrak industrial process photometers - Beers law

A = ε l c
absorbance (= – log transmittance)
molar absorptivity coefficient
optical path length
concentration of absorbing species

The Kemtrak DCP007 photometer is ideally suited for industrial environments where simplicity, stability and low maintenance is vital.


Stainless steel EN 1.4301 (X5CrNi18-10), AISI 304 (V2A)
Captive lid screws & external mounting brackets stainless steel
244 x 215 x 105 mm (L x W x D)
IP 65 / EN 60529
16 x 4 alphanumeric white on blue dot matrix LCD display
LED background illuminated
Measurement updates every second
LED 1 (green): Power on
LED 2 (red): System fault
LED 3 & 4 (orange): Alarm 1 & Alarm 2
LED 5 (blue): Clean / Hold
4 push buttons
Remote HTML/Java interface (TCP/IP connection via Ethernet port)
Software Features:
• Auto gain: Fully automatic photometer gain switching
• Auto zero: Automatically, locally or remotely activated zero
• Calibration: 16 linearization tables for concentration & mA output
• Damping: From 0 to 9999s with noise (air bubble / particle) filter
• Memory: Nonvolatile – all data retained upon power failure
• Security: Alphanumeric password protection
Data Logger
• >17000 data points (timestamp, average, max. & min.), ring buffer
• Configurable log time interval 1s to 24hr
Event Logger
• >16000 events, ring buffer
• Timestamp, alarms, zeroing, cleaning, product change, calibration &
system events (power, system warning & error messages)
Automatic Cleaning Control
• Automatic cleaning sequence, triggering dedicated relay output
• Manual trigger or external trigger via digital input
• Configurable automatic cleaning interval, 15min to 2months
• Configurable cleaning duration from 0 to 9999s
• Auto-zero after clean option
• Hold value after clean (to equilibrate) 0 to 9999s
PID Controller
Control method: Pulse width modulated relay output or
0/4-20mA output
Control period: 2 – 99s
Proportional gain: 0.0000 – 999999
Integral time: 0.0000 – 999999s
Derivative time: 0.0000 – 999999s
Remote Input
5 x Digital input (potential free contact) for:
• Input 1-3: Product/range selection
• Input 4: Zero, instant zero, clean or clean & Zero
• input 5: Hold (freeze output), data log control or light source control

Light Source
High performance light emitting diode (LED)
Wavelength range: 350 – 1050nm
Full Width-Half Maximum (FWHM): 10nm
Central Wavelength (CWL) Accuracy: ±1nm
Typical lamp lifetime: >100000hrs
Note: Measurement wavelengths must be factory installed.
Typical specifications provided for 500nm
Photometric Range
0.000 – 5AU at 500nm, 10mm OPL
Photometric Accuracy
±0.001AU at 1AU
Photometric Noise
±0.0001AU at 1AU
± 0.5% of respective measuring range
mA Output
1 x selectable 0 – 20mA / 4 – 20mA (NAMUR, max 21.6mA)
Optional second mA output
Galvanically isolated, tested during final inspection to 500 VDC
Accuracy: < 0.1%
Resolution: 0.025%
Load: 0 – 600Ohm
Relay Outputs
1 x 1A 240VAC Failsafe output (active when system is ok)
2 x 1A 240VAC User configurable (alarm, PID)
1 x 1A 240VAC Automatic cleaning control
Fuses: 4 x 1A (type: MXT), max 100A breaking capacity
LED status indicators flash when relays are active
Dedicated relay output, 1A 240 VAC
mA output value used to signal a system fault (NAMUR <3.6mA or >21.0mA)
Network interface (remote communications):
TCP/IP, 10Base-T and 100Base-TX Link
Connector: RJ45
1) HTML/Java interface using native protocol over TCP/IP
Software: Web browser with Java version 6 or later
2) MODBUS server (slave) over TCP/IP (V1.1b3 compliant)
Functions: (0x03, 0x04, 0x2B/0x0E – conformity 0x01)
Operating Conditions
Ambient temperature: 0°C to +50°C (32°F to 122°F)
Transport: -20°C to +70°C (-4°F to 158°F)
Power Supply
100-240VAC, 50-60Hz, & 22 – 30VAC/VDC
Mains fuse: 1A (type MST), Max breaking capacity 35A

ISO 9001:2008, CE, ATEX Ex d IIB + H2 T5 IP66 Category II 2 G (option)

The Kemtrak DCP007 color & concentration analyzer consists of three components:

  1. Control Unit. The control unit contains allelectronics including light source and detectors.
  2. Measurement Cell. Robust in-line (flow through) industrial process connection.
  3. Fibre Optics. Industrial grade fibre optic assembly connects the control unit to the flow-cell.


The configuration shown here is a 316L stainless steel DIN DN50 flange measurement cell with stainless steel fully interlocked fibre optic assembly. Both measurement cell and fibres can withstand 250°C (482°F)

Industrial in-ine fiber optic photometer for chemical, color, concentration, hazen, platinum cobalt, chlorine, chlorine dioxide, ICUMSA, ASTM and saybolt.