The EC TDS temperature tester HI98312, better known as the Hanna DiST 6, is a waterproof three-in-one pocket meter that reports electrical conductivity, total dissolved solids and temperature from a single graphite probe. It turns a job that once needed a benchtop instrument into a ten-second check you can run anywhere on site.

EC TDS temperature tester HI98312 Hanna DiST 6 waterproof pocket meter

Why the HI98312 EC TDS temperature tester is a site favourite

When the original DiST was launched it made conductivity and dissolved solids testing affordable for everyone, and the DiST 6 carries that idea forward. One button gives you a stable conductivity reading, a second press converts it to TDS, and the temperature value updates alongside it. Because all three parameters come from the same probe there is nothing to swap, nothing to rinse twice and no second instrument to keep calibrated.

High-range measurement for treated and raw water

Conductivity: 0.00 to 20.00 mS/cm, resolution 0.01 mS/cm, accuracy ±2% F.S.
TDS: 0.00 to 10.00 g/L (ppt), resolution 0.01 g/L, accuracy ±2% F.S.
Temperature: 0.0 to 60.0 °C / 32.0 to 140.0 °F, resolution 0.1°, accuracy ±0.5 °C

That high range covers everything from softened municipal supply and RO feed water to brackish bore water and nutrient solutions, so one meter handles most of a service engineer’s day.

Replaceable graphite electrode

The HI73311 graphite electrode resists the salt deposits and contamination that ruin stainless steel pins, which keeps readings honest over a long service life. When the probe finally wears out you simply unscrew it with the supplied HI73128 removal tool and fit a new one instead of replacing the whole meter.

Temperature compensation you can tune

Automatic temperature compensation is applied to every reading, and the beta coefficient is adjustable from 0.0 to 2.4% per °C so you can match the chemistry of the solution you actually work with. The EC to TDS conversion factor is adjustable from 0.45 to 1.00, which lets the meter agree with whatever standard your laboratory or client specifies.

Waterproof, floating and built for the field

The casing is fully waterproof and, unusually, designed to float, so a dropped meter is retrieved rather than lost down a tank. A HOLD button freezes the reading so you can lift the probe out and write the value down, and the BEPS battery error prevention system warns you when power is too low to give a trustworthy result. Auto shut-off kicks in after eight minutes of inactivity, and four 1.5V batteries deliver roughly 100 hours of continuous use.

Simple one-point automatic calibration

Calibration is automatic at a single point, either 12.88 mS/cm for conductivity or 6.44 g/L for TDS. Three sachets of each standard ship in the box, so the tester is ready to certify from the moment it is unpacked. A quick calibration before an important set of readings takes under a minute.

Where an EC TDS temperature tester is used

Reverse osmosis plants: feed, permeate and reject checks, plus membrane performance tracking
Water softeners and demineralisation plants: verifying regeneration and resin condition
Drinking water quality checks in homes, villas, schools and hotels
Hydroponics, greenhouses and landscaping irrigation nutrient control
Aquariums, fish farms and swimming pools
Boilers, chillers and cooling towers where dissolved solids must stay in range
Laboratories, food and beverage production and general QC sampling

Technical specifications

SKU	HI98312
EC range / resolution / accuracy	0.00 to 20.00 mS/cm \| 0.01 mS/cm \| ±2% F.S.
TDS range / resolution / accuracy	0.00 to 10.00 g/L (ppt) \| 0.01 g/L \| ±2% F.S.
Temperature range / resolution / accuracy	0.0 to 60.0 °C (32.0 to 140.0 °F) \| 0.1° \| ±0.5 °C
Calibration	Automatic, one point at 12.88 mS/cm or 6.44 g/L
Temperature compensation	Automatic, beta adjustable 0.0 to 2.4% / °C
EC to TDS factor	Adjustable from 0.45 to 1.00
Probe	HI73311 replaceable EC/TDS graphite electrode (included)
Auto shut-off	After 8 minutes of non-use
Power	4 x 1.5V batteries, approx. 100 hours continuous use
Environment	0 to 50 °C (32 to 122 °F), RH max 100%
Dimensions / weight	163 x 40 x 26 mm (6.4 x 1.6 x 1.0 in) \| 100 g
Warranty	1 year

What is in the box

HI98312 meter with HI73311 EC/TDS graphite probe fitted
HI70030 12880 µS/cm conductivity standard, 20 mL sachets (3 pcs)
HI70038 6.44 ppt TDS standard, 20 mL sachets (3 pcs)
HI73128 probe removal tool
1.5V batteries, quality certificate and instruction manual

Frequently asked questions

What is the difference between EC and TDS?

Electrical conductivity measures how easily a current passes through water, which depends on the dissolved ions present. TDS is that same measurement converted into an estimated weight of dissolved solids using a conversion factor. This EC TDS temperature tester displays both, so you can quote whichever figure your report needs.

How often should the tester be calibrated?

Calibrate weekly for routine service work, or before any set of readings that will be recorded on a certificate. Always calibrate after fitting a new probe.

Can the probe be replaced?

Yes. The HI73311 graphite electrode is a user-replaceable spare, which makes the HI98312 far more economical over its life than sealed testers.

Is the meter suitable for reverse osmosis permeate?

It is ideal for feed, reject and general process water. For very pure permeate below roughly 10 ppm a dedicated low-range meter will give finer resolution.

Buy the EC TDS temperature tester HI98312 in Oman

Water Filter Oman stocks genuine Hanna Instruments testing equipment with local support and quick delivery to Muscat, Sohar, Salalah and across the Sultanate. Explore our full range of water testing meters and instruments, or talk to our team about calibration standards, spare probes and bulk pricing for service contracts. Manufacturer documentation for this model is published on the Hanna Instruments DiST 6 page.

TDS meter Oman

EC TDS Temperature Tester HI98312 – Hanna DiST 6 Waterproof Meter