Portable instrument MFD79

The MFD79 is a compact measuring device, suitable especially for operative measurements in the field or industrial technologies, or for occasional use in the laboratory. The device is available with different input configurations, allowing simultaneous measurement of one or two quantities (with corresponding sensors) as well as temperature.

Operation of the device is easy thanks to the high-contrast dot-matrix LCD display, which is easy to read in the dark and in the sun, and a simple menu-based system controlled by only 6 buttons. Several levels of password protection protect the device against unwanted changes to the settings, or against unwanted interventions by less qualified operators or unauthorized persons. Semi-automatic calibration procedures greatly facilitate the preparation for measurements.

The MFD79 is suitable for a wide range of applications thanks to its small size and weight, high degree of protection and easily replaceable batteries of commonly available type (AA), with a long battery life ensured by low device consumption. In the field, the device and sensors are best protected by the recommended transport cover, which also protects against water immersion and drop damage (to some extent).

Log of measured values is an additional function that records the measured data in the device for later inspection (only on the device display). The data may also be displayed in the form of simple graphs.

An alternative for more demanding applications is the MFD80 instrument with extended range of supported measurements, support for data interfaces and a number of other improvements.

Oxygen concentration measurement

The MFD79 instrument is offered in two variants, depending on the type of oxygen sensor supported. Modern optical oxygen sensors CSOT53L (supported in the red version of the device) are characterized by greater endurance and long life of the membrane, zero consumption of oxygen during measurement and minimal maintenance requirements (virtually no need for recalibration).

To measure high oxygen concentrations, or when the fastest possible response of the sensor is required, the classic sensor of the Clark type CSOT43L (supported in the blue version of the device) may be more suitable. Even these sensors are characterized by a very low oxygen consumption, allowing for measurements in still water. Thanks to the advanced design of INSA instruments, there is also no need to wait for the polarization of the sensor, which is maintained even when the device is switched off.

The measured data may be displayed as concentration (mg/l) or as percentual saturation. All INSA oxygen sensors are also equipped with temperature measurement and automatic temperature correction.

pH and ORP measurements

Classic glass sensors with an integrated reference electrode are used for pH measurement. The supplied sensors are equipped with plastic transport covers.

ORP can also be measured through the same input of the device if a corresponding sensor is connected. Separately stored calibration enables alternating measurements of both quantities (only one at a time).

Additional measurement of temperature

All inputs of the MFD79 device also support temperature measurement. Each connected sensor can therefore be equipped with an integrated temperature sensor, or a separate temperature sensor (type TTK21L) may be connected to any input. Any available temperature reading may be used for temperature correction of the measurement.

Dimensions	120 x 65 x 22 mm
Weight	ca 200 g
Enclosure	IP 54
Power supply	2x AA size batteries (alkaline 3 V or NiMH 2.4 V)
Battery life	ca 300 - 1000 h (backlight off, depends also on configuration and battery type)
Data log capacity	min. 500 values
Digital interfaces	none

Version	MFD79 OPTO	MFD79
Color code	Red	Blue
Oxygen input compatibility	Optical sensor CSOT53L	Clark-type sensor CSOT43L
Oxygen measurement range	0.1 - 20 mg/l or 0.1 - 150 %	0.1 - 30 mg/l or 0.1 - 200 %
Oxygen measurement accuracy	± 1 % (of full scale, at 25 °C)
pH measurement range	0 - 14
pH measurement accuracy	± 0,5 % (of full range, at 25 °C)
pH calibration	2 points
ORP measurement range	± 1000 mV
ORP measurement accuracy	± 1 mV
Temperature measurement range	-4 to +50 °C
Temperature measurement accuracy	± 0.2 °C