Keterangan
The HD2156.1 and HD2156.2 are portable instruments with a large LCD display. They measure pH, mV, redox potential ( ORP) , conductivity, liquid resistivity, total
dissolved solids ( TDS) and salinity using combined 4-ring and 2-ring conductivity/
temperature probes. Temperature only is measured by Pt100 or Pt1000 immer-
sion, penetration or contact probes.
The pH electrode calibration, as well as manual, can be carried out on one, two or three points and the calibration sequence can be chosen from a list of 13 buffers. The probe calibration can be performed automatically in one or more of the 147¼ S, 1413¼ S, 12880¼ S or 111800¼ S/ cm conductivity calibration solutions. The HD2156.2 instrument is a datalogger. It memorizes up to 20, 000 sets of
three measurements composed of pH or mV, conductivity or resistivity or TDS or salinity and temperature: these data can be transferred from the instrument connected to a PC via the multi-standard RS232C serial port and USB 2.0. The
storing interval, printing, and baud rate can be configured using the menu. The HD2156.1 and HD2156.2 models are fitted with an RS232C serial port and can transfer the acquired measurements to a PC or to a portable printer in real time.
The Max, Min and Avg function calculates the maximum, minimum or average values. Other functions include: the Auto-HOLD function and the automatic turning off which can also be disabled.
The instruments have IP67 protection degree.
INSTRUMENT TECHNICAL CHARACTERISTICS
Instrument
Dimensions
( Length x Width x Height) 185x90x40mm
Weight 470g ( complete with batteries)
Materials ABS, rubber
Display 2x41D2 digits plus symbols
Visible area: 52x42mm
Operating conditions
Working temperature -5� 50° C
Storing temperature -25� 65° C
Working relative humidity 0� 90% RH without condensation
Protection degree IP67
Power
Batteries 4 1.5V type AA batteries
Autonomy 200 hours with 1800mAh alkaline batteries
Power absorbed with instrument off 20¼ A
Mains Output mains adapter 9Vdc / 250mA
Security of memorized data Unlimited, independent of battery charge
conditions
Time
Date and time Schedule in real time
Accuracy 1min/ month max error
Measured values storage - model HD2156.2
Type 2000 pages containing 10 samples each
Quantity 20, 000 sets of three measurements composed
of pH or mV, � or © or TDS or salinity and temperature.
Storage interval 1s� 3600s ( 1hour)
Serial interface RS232C
Type RS232C electrically isolated
Baud rate Can be set from 1200 to 38400 baud
Data bit 8
Parity None
Stop bit 1
Flow Control Xon/ Xoff
Serial cable length Max 15m
Immediate print interval 1s� 3600s ( 1hour)
USB interface - model HD2156.2
Type 1.1 - 2.0 electrically isolated
Connections
pH/ mV input Female BNC connector
Conductivity input 8-pole male DIN45326 connector
Serial interface and USB 8-pole MiniDin connector
Mains adapter 2-pole connector ( positive at centre)
Measurement of pH by Instrument
Measurement range -2.000� + 19.999pH
Resolution 0.01 or 0.001pH selectable from menu
Accuracy ± 0.001pH ± 1digit
Input impedance > 1012©
Calibration error @ 25° C | Offset| > 20mV
Slope > 63mV/ pH or Slope 106.5% or Sensitivity < 85%
Measurement of mV by Instrument
Measurement range -1999.9� + 1999.9mV
Resolution 0.1mV
Accuracy ± 0.1mV ± 1digit
Drift after 1 year 0.5mV/ year
Measurement of conductivity by Instrument
Resolution with K cell= 0.1 0.01¼ S/ cm in range 0.00� 19.99¼ S/ cm
Measurement range ( K cell= 1)
Resolution 0.0� 199.9¼ S/ cm / 0.1¼ S/ cm
200� 1999¼ S/ cm / 1¼ S/ cm
2.00� 19.99mS/ cm / 0.01mS/ cm
20.0� 199.9mS/ cm / 0.1mS/ cm
Accuracy ( conductivity) ± 0.5% ± 1digit
Measurement of resistivity by Instrument
Measurement range / Resolution 4.0� 199.9© / 0.1©
200� 999© / 1©
1.00k� 19.99k© / 0.01k©
20.0k� 99.9k© / 0.1k©
100k� 999k© / 1k©
1� 10M© / 1M©
Accuracy ( resistivity) ± 0.5% ± 1digit
Measurement of total dissolved solids ( with coefficient � / TDS= 0.5)
Resolution with K cell= 0.1 0.05mg/ l in range 0.00� 19.99mg/ l
Measurement range
( K cell= 1) / Resolution 0.0� 199.9 mg/ l / 0.5 mg/ l
200� 1999 mg/ l / 1 mg/ l
2.00� 19.99 g/ l / 0.01 g/ l
20.0� 199.9 g/ l / 0.1 g/ l
Accuracy ( total dissolved solids) ± 0.5% ± 1digit
Measurement of salinity
Measurement range / Resolution 0.000� 1.999g/ l / 1mg/ l
2.00� 19.99g/ l / 10mg/ l
Accuracy ( total dissolved solids) ± 0.5% ± 1digit
Automatic/ manual temperature
compensation 0� 100° C with ± T that can be selected from
0.00 to 4.00% / ° C
Reference temperature 20° C or 25° C
� / TDS conversion factor 0.4� 0.8
Cell constant K ( cm-1) 0.1, 0.7, 1.0 and 10.0
Standard solutions automatically detected ( @ 25° C)
147 ¼ S/ cm
1413 ¼ S/ cm
12880 ¼ S/ cm
111800 ¼ S/ cm
Measurement of temperature by Instrument
Pt100 measurement range -50� + 200° C
Pt1000 measurement range -50� + 200° C
Resolution 0.1° C
Accuracy ± 0.25° C
Drift after 1 year 0.1° C/ year