Hanna Instruments

Scientific Equipment

HI-981420 Groline Monitor

HI-981420 Groline Monitor

HI-981420 Groline Monitor

HI-981420 Groline Monitor

3-in-1 pre-amplified probe measures pH, EC/TDS
New green light technology
In Stock
£295.83 (exc. VAT) £355.00 (inc. VAT)

The HI-981420 GroLine Monitor provides 24 hour continuous monitoring of pH, conductivity (EC or TDS), and temperature in hydroponic nutrients.


Results every 15 minutes . . .

The GroLine Monitor automatically logs your results every 15 minutes over the last 30 days. Minimum, maximum, and average values are stored so you can recognise when patterns arise and help prevent future problems.

Simultaneous display of all 3 essential readings on an easy to read large LCD with plant-safe green backlighting.

No need for separate probes. Supplied complete with a durable, polypropylene body 3-in-1 probe which measures pH, EC/TDS, and temperature.

Frequently Bought Together

Price for all:
£325.83
Buy All 2 for: £309.54

HI-981420 Groline Monitor information

Hanna's extended description

HI-981420 GroLine monitor

Make your nutrient solution easy to manage with the GroLine Monitor and combined pH/EC/Temperature probe. Quick to setup and simple to use, the monitor was designed for hydroponics, aquaponics, and greenhouses.


Benefits include:

  • High and low alarms with LED indicator
  • Easy viewing on the large LCD with plant-safe green backlighting
  • Calibrate pH and EC with a single Quick Cal solution

Measure like a pro . . . !

The GroLine Monitor has been developed by growers and scientists who are committed to helping you take your growing operation to the next level.


At a glance . . .

A large clear LCD shows all of your essential readings so you know what your water is doing 24/7. High and low alarms flash to warn you if something needs adjusting.

Professional accuracy

Advanced algorithms and greater pH and TDS/ppm accuracy ensure operational consistency and a finer understanding of your plant’s needs.


One probe. Three measurements.

The 3-in-1 pre-amplified probe measures pH, EC/TDS, and temperature in a single, durable, polypropylene body making the GroLine Monitor easy to handle and easy to set up.


Quick Cal . . .

A single calibration solution for pH and conductivity makes calibration fast and ensures all of your measurements are accurate resulting in better plant health and better yield.

Key features

  • 3 sensors combined in a single rugged probe body: pH electrode with renewable cloth junction, amperometric EC/TDS sensor, and an internal temperature sensor for temperature compensated readings
  • IP65 rated enclosure: designed to withstand harsh growing environments
  • Wide pH Range: measure pH from 0.00 to 14.00 pH
  • Selectable EC to TDS ppm conversion factor: choice of either a 0.5 or 0.7 conversion factor
  • Ambient light sensor: for automatic LCD dimming

  • Automatic Temperature Compensation: all readings are compensated for variations in temperature, temperature displayed in °C or °F along with pH, EC or TDS reading
  • Large LCD with plant-friendly green backlighting: meter displays a clock tag that will disappear when the reading has achieved stability
  • Data logging for 30 days: logs every 15 minutes for last 30 days, stores min, max, and average values
  • Data transfer: USB-C port for easy data transfer to memory stick or PC
  • High and low alarms with LED indicator: warns when process is out of desired range by flashing display and message
  • Specifications

    Specifications list

    Specifications

    pH Specifications
     pH Range 0.00 to 14.00 pH
     pH Resolution 0.01pH, (0.1pH)
     pH Accuracy ±0.05pH, (±0.1pH)
     pH Calibration Automatic buffer recognition, at one or two points using standard buffers (pH4.01, 7.01, 10.01)
     Temperature Compensation Automatic
    Conductivity – EC/TDS Specifications
     EC Range 0.00 to 10.00 mS/cm
     EC Resolution 0.01mS/cm
     EC Accuracy ±0.1 mS/cm (0 to 5 mS); ±0.2 mS/cm – 10 mS/cm)
     EC Calibration Automatic recognition, one-point at 1.41 mS/cm or5.00 mS/cm
     EC/TDS Temperature compensation Automatic with β set at 1.9%/°C
     TDS Range 0 to 5000 ppm (TDS conversion factor 0.5 (0.5 CF)); 0 to 7000 ppm (TDS conversion factor 0.7 (0.7 CF))
     TDS Resolution 10ppm
     TDS Accuracy ±2% f.s.
    Temperature Specifications
     Temperature Range 0.0 to 60.0°C
     Temperature Resolution 0.1°C
     Temperature Accuracy ±0.5°C
    General specifications
     Display 128 x 64 pixel B/W LCD with green backlight
     Connectivity USB Type-C
     IP Rating IP65
     Alarms High and low with enable/disable option for all parameters
     Log Feature Automatic logging for last 30 days at 15 minute intervals
     GLP Last 5 calibrations with date and time stamp
     Probe HI-1285-8 polypropylene body, pre-amplified multiparameter probe with internal temperature sensor, DIN connector and 2m cable
     Power supply 12VDC adapter (included)
     Environment -5 to 50°; RH max 95% non-condensing
     Dimensions 125 x 185 x 38mm
     Weight 333g
     Ordering Information HI-981420 is supplied with HI-1285-8 multiparameter probe, HI-50036-0 Quick Cal buffer solution sachet (3), HI-700661 pH electrode cleaning solution sachet for agriculture (3), DC Power adapter (1), and instructions.
     Warranty 2 years (probe 6 months)
    Compatible solutions: HI-50036p Quick Calibration Solution for GroLine pH and EC Meters, 25 sachets; HI-5036-023 Quick Calibration Solution for GroLine pH and EC Meters, 230 mL; HI-7061-023 GroLine General Purpose Cleaning Solution, 230 mL; HI-70300-023 GroLine Electrode Storage Solution, 230 mL. HI-7004-023 GroLine pH 4.01 Calibration Buffer, 230 mL; HI-7007-023 GroLine pH 7.01 Calibration Buffer, 230 mL; HI-7010-023 GroLine pH 10.01 Calibration Buffer, 230 mL.

    Product Literature

    literature - PDF

    Hanna Instruments Literature

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