Hanna Instruments

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BL-983321-0 TDS Mini Controllers (Range 0.00 to 19.99 ppm)

BL-983321-0 TDS Mini Controllers (Range 0.00 to 19.99 ppm)

Hanna BL-983321-0 TDS Mini Controllers (Range 0.00 to 19.99 ppm)

BL-983321-0 TDS Mini Controllers (Range 0.00 to 19.99 ppm)

Complete with mounting brackets
2 year manufacturer warranty
In Stock
£190.00 (exc. VAT) £228.00 (inc. VAT)

The instruments have been designed for TDS control in hydroponics, horticulture and water conditioning. The BL-983321 is a compact, panel mounted, process controller for measuring total dissolved solids (TDS) of a process stream that is within the 0.00 to 19.99 ppm (mg/L) range. The device features a large LCD with protective cover.

BL-983321-0 TDS Mini Controllers (Range 0.00 to 19.99 ppm) information

Hanna's extended description

Users may choose from automatic or manual dosing modes. When in automatic mode the dry contact relay is activated when a reading is above the set point. The relay can be used to activate a solenoid that switches from one DI (deionised) tank to another or to open a valve that will allow lower TDS water to flow into a tank being monitored in order to lower its TDS. The BL-983321 can also be used to monitor the quality of water produced from ion exchange, reverse osmosis (RO) or distillation.

*The BL-983321 uses a 0.5 conversion factor in which 1.00 μS/cm = 0.50 ppm.

Adjustable Dry Contact Dosing Relay

The BL-983321 features a dosing relay that is activated when the reading is above a user programmable set point.

Programmable Overdose Protection

For enhanced safety the mini controller can be programmed to deactivate the dosing relay if the set point is not reached within a specified time interval. The overdosing timer is programmable from 5 to 30 minutes or disabled.

Relay Control Override

With the flick of a switch the mini controller's relay can be disabled (Off), placed in control (Auto), or be activated for manual operation (On) which is useful for priming a dosing pump.

Multicolour LED Indicator

Multicolour LED indicator allows an operator to quickly check the status of the controller.

  • Green = Meter in measurement mode and reading is below the set point
  • Orange/Yellow = Reading is above the set point and the relay is activated
  • Blinking Red = Indicates an alarm condition such as when the maximum dosing time has been exceeded

  • Fuse Protected Dosing Contacts

    The relay dosing contact is rated for up to a 2A load and is fuse protected.

    Labelled Termination Connections

    Quick-connect terminal blocks are clearly labelled for easy connection to power, conductivity probe and relay that can be used to operate a dosing pump, valve, audible alarm, or light.

    1/2" NPT Male Threaded Amperometric Probe for Mounting In-line*

    The BL-983321 mini controller uses the HI-7634-00 conductivity probe that is available with different cable lengths.

    *HI-7634-00 is not included and must be ordered separately.

    Order Information:

    The BL 983321 is supplied with mounting brackets, transparent cover, and instructions.

    Mains powered - All mains operated equipment is compatible with UK AC voltage and frequency – 230V, 50Hz.

    Water Resistant – Can withstand temporary exposure to water, but should not be submerged or washed under running water.


    Specifications list


    Range 0 to 19.99 ppm
    Resolution 0.01 ppm
    Accuracy ±2% F.S.
    TDS Conversion Factor 0.5
    Probe HI 7634-00 (not included)
    Temperature Compensation Automatic, 5 to 50°C (41 to 122°F) with ß = 2%/°C
    Calibration manual, with CAL trimmer
    Dosing Relay 1, max 2A (fuse protected), 250 Vac, 30 Vdc
    contact closed when reading exceeds setpoint value
    Setpoint adjustable from 0 to 19.99 ppm
    Overtime adjustable, typically from 5 to approx. 30 minutes
    Power Supply 12 VDC adaptor included
    Dimensions 83 x 53 x 99 mm (3.3 x 2.1 x 3.9")
    Weight 200g

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