Section 1 specifications – Hach-Lange 1720E Low Range Turbidimeter User Manual
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Section 1
Specifications
Specifications are subject to change without notice.
Table 1 1720E Low Range Specifications
Range
0–100 nephelometric turbidity units (NTU)
Measurement Units
mg/L, NTU, TE/F, FTU, Degree
Accuracy
1
± 2% of reading or ± 0.02 NTU (whichever is greater) from 0 to 40 NTU;
± 5% of reading from 40 to 100 NTU (when calibration is performed at 20.0 NTU with the
offset turned off).
Linearity
Better than 1% 0–40 NTU on formazin. Allows for accurate calibration at high turbidity values.
Resolution (Displayed)
0.0001 NTU
up to 9.9999 NTU; 0.001 NTU from 10.000 to 99.999 NTU; 0.01 NTU at 100.00
NTU
Repeatability
Better than ±1.0% of reading or ±0.002 NTU, whichever is greater
Response Time
For a full-scale step change, initial response in 1 minute, 15 seconds. Varies with flow rate,
see the table below. The response time is also dependent on the signal averaging time, which
is user selectable.
Sample Flow Required
250 to 750 mL/minute
Storage Temperature
–20 to 60 °C (–4 to 140 °F)
Operating Temperature
0 to 50 °C (32–122 °F) for single sensor system, 0 to 40 °C (32–104 °F) for two sensor system
Sample Temperature
Range
0 to 70 °C
Operating Humidity
5 to 95% non-condensing
Power Requirements
12 VDC ± 5%, 12.5 Watts maximum
Sample Inlet Fitting
1
/
8
barb fitting to ¼-inch NPT male adapter
Signal Average Time
no averaging, 6, 30, 60, and 90 seconds, user selectable. Default is 30 seconds.
Dimensions
Turbidimeter body and cap: 25.4 x 30.5 x 40.6 cm (10 x 12 x 16 inches)
Sensor Cable Length
2 m (6.6 ft); Optional 7.62 m (25 ft)
Mounting Options
Turbidimeter Body and Head Assembly: Wall; floor stand
Shipping Weight
1720E Series 2 Turbidimeter and Controller: 6.31 kg (13.5 lb); 1720E Turbidimeter only: 4.71
kg (10 lb)
Calibration Methods
1.
StablCal
®
(stabilized formazin) – primary or wet calibration of the instrument.
Recommended at 20.0 NTU.
2.
Formazin – user-prepared primary or wet calibration of the instrument. Recommended at
20.0 NTU.
3.
Multi-sensor calibration – Performed with a specialized calibration procedure for up to
eight sensors on a single set of fresh StablCal
®
standards.
% Step Change
Flow Rate
750
500
250
10
1¼ minutes
1½ minutes
2½ minutes
50
2 minutes
2½ minutes
6 minutes
90
3½ minutes
3½ minutes
9 minutes
99
4 minutes
5 minutes
12 minutes