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

In Stock 3 Items available


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.

Conductivity & TDS

£225.80 (exc.VAT)
£270.96 (tax incl.)
Full Description Specification Manuals

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.

Read More

Range0 to 19.99 ppm
Resolution0.01 ppm
Accuracy±2% F.S.
TDS Conversion Factor0.5
ProbeHI 7634-00 (not included)
Temperature CompensationAutomatic, 5 to 50°C (41 to 122°F) with ß = 2%/°C
Calibrationmanual, with CAL trimmer
Dosing Relay1, max 2A (fuse protected), 250 Vac, 30 Vdc
contact closed when reading exceeds setpoint value
Setpointadjustable from 0 to 19.99 ppm
Overtimeadjustable, typically from 5 to approx. 30 minutes
Power Supply12 VDC adaptor included
Dimensions83 x 53 x 99 mm (3.3 x 2.1 x 3.9")