Hanna HI8734 Three-Range Portable TDS Meter 0-19.99 g/L

Hanna HI8734 three-range portable TDS meter

The Hanna HI8734 is a portable total dissolved solids meter with three ranges from 0.0 mg/L to 19.99 g/L, supplied with the HI76301D four-ring conductivity probe. It converts conductivity to TDS using a 0.5 factor and suits water-quality checks where the limit is written as mg/L. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.

It uses the same manual as the HI8733 EC meter, but the model number selects TDS units, a three-position range switch and a calibration sachet of 1382 mg/L (HI70032).

HI8734 technical specifications

How the HI8734 works

The meter measures the conductivity of the sample through a four-ring probe and multiplies it by a conversion factor of 0.5 to display TDS. The factor is a convention and real TDS depends on the ion mix, so for non-standard waters a laboratory gravimetric comparison can be used to check suitability.

Temperature correction on this model is fixed to a beta coefficient of 2 % per degree C and applied for samples between 0 and 50 °C, so very precise work should measure close to 25 °C. Calibration is a single manual adjustment of the TDS knob with the probe in the HI70032 1382 mg/L standard.

Where HI8734 fits: sensors, accessories and related models

The HI76301D four-ring probe is supplied with the meter. Four-ring designs are less sensitive to coating and sample volume than two-pole cells, which helps in dirty process waters. Calibration standards beyond the 1382 mg/L sachet are separate consumables.

The table contrasts the HI8734 with the HI8733, since buyers sometimes order the wrong parameter.

HI8734 family comparison

If your specification mentions both conductivity and TDS, the HI98195 or HI98194 multiparameter meters give EC, TDS, salinity and resistivity together from a single probe.

Selection and ordering checklist for HI8734

• Confirm TDS in mg/L or g/L is the required unit
• Check that the 0.5 conversion factor suits your water, or plan laboratory cross-checks
• Quote additional calibration standards if needed
• Decide on a spare HI76301D probe
• Plan for a 9 V alkaline battery

Installation, calibration and maintenance of HI8734

Rinse the probe with deionised water and the sample, immerse it fully and tap out bubbles, then calibrate with the TDS knob in the 1382 mg/L standard on the matching range. Recalibrate each shift or after a range change.

Clean the four rings with the manual-recommended method if a film forms, avoid scratching them, and store the probe clean and dry. Because temperature compensation is fixed, let cold or hot samples approach room temperature before the final reading.

In field audits it is useful to note the sample temperature next to the TDS value, because a reading taken at 40 °C with a fixed beta of 2 % per degree carries more uncertainty than one at 25 °C.

Keep a small bottle of calibration standard in the carrying kit and replace it after it has been opened for some weeks, since evaporation and contamination alter its value.

Because TDS values are derived and not measured directly, state the conversion factor used whenever results are reported, so that a reader who prefers a different factor can recompute. When comparing two sites, use the same range, the same temperature and the same calibration standard, and avoid reading in moving water that carries air bubbles past the rings. A short soak in deionised water between samples prevents carry-over between very different TDS levels. If the instrument will be used in the field for several days, carry spare batteries, because a weak 9 V cell causes unstable readings before it fails completely, and check the probe cable for kinks after each trip.

Typical applications of HI8734 in Oman and the GCC

Typical uses in Oman include screening of drinking water and bottled water, reverse-osmosis permeate checks, irrigation and aquaculture water assessment, cooling-water and boiler make-up screening, and quick TDS verification at tanker filling points.

The three-range switch lets one meter handle both low-TDS permeate and higher-TDS brackish sources without changing the probe.

Information to send with an RFQ for HI8734

• Quantity and spare probes
• Calibration standards required
• Expected TDS range and application
• Delivery location and lead time
• Project or tender reference

Storage, handling and spares for the Hanna HI8734

Store the Hanna HI8734 in its case in a clean, dry place. Keep probes, electrodes and reagents as described in the user manual, as many of them need a storage solution or have a limited shelf life. In the GCC climate, keep reagents away from heat and direct sun and check expiry dates before use.

• Calibrate the instrument with fresh standards at the interval your procedure requires.
• Rinse probes and sample cells after each use and inspect them for scratches or deposits.
• Keep spare consumables, such as reagents, standards, cuvettes and electrode solutions, in stock.
• Record calibration results so that drift or probe ageing can be seen early.

When you order the Hanna HI8734, list the consumables and standards you need in the same RFQ, so the instrument can be used from the day it arrives.

Documents and quotation

The instruction manual for the HI8734 is attached on this page for specifications, calibration procedures and maintenance steps. The same document covers the HI8733.

Send the part number HI8734, the quantity and your delivery location and we will reply with availability and a quotation.