TDS | Thermometer Handheld Pen Meter
R250.00
The TDS | Thermometer Handheld Pen Meter is a practical accessory for water treatment and filtration setups. In stock now at Monster Mechanical.
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TDS-3: Handheld TDS Meter with Carrying Case
The Handheld TDS Thermometer Pen Meter is a compact, accurate tool designed for measuring Total Dissolved Solids (TDS) and water temperature in a wide range of applications. It helps you assess water purity quickly — whether for filtration systems, water dispensers, aquariums or food processing. Because it features a dual‑range measurement and built‑in thermometer, you can track both dissolved solids and temperature to ensure optimal water quality.
Key Features
- Dual‑Range TDS Measurement: Reads 0‑999 ppm with 1 ppm resolution, and up to 9990 ppm with 10 ppm resolution.
- Integrated Temperature Read‑out: Measures water temperature so you can interpret TDS results accurately.
- Hold Function: Freezes the reading on screen for easy recording and review.
- Auto‑Off Function: Automatically powers down after a period of inactivity to save battery.
- Portable and Easy to Use: Compact pen design allows users to carry it, test on the go, and store it easily.
- Wide Application Use: Suitable for home drinking water, water dispensers, hydroponics, aquariums, and food‑service systems.
Technical Specifications
- Accuracy: ±2% typical.
- Measurement Range: 0‑999 ppm (1 ppm resolution); 1 000‑9990 ppm (10 ppm resolution)
- Size & Weight: Approx. 155 mm × 28 mm × 15 mm; 68 g weight.
- Battery: 2 × 1.5 V button‑cell batteries included.
- Range of Use: Drink water testing, RO systems, aquariums, hydroponics, pools, spas.
Why Use the Handheld TDS Thermometer Pen Meter?
Monitoring TDS levels ensures your water system performs correctly. Moreover, high TDS can signal filter/membrane failure or contamination — so this meter gives you a quick diagnostic tool. For example, when the reading spikes above expected levels, you may need to service or replace the filter cartridge. In addition, tracking temperature helps you interpret readings accurately since TDS results can vary with water temperature. Altogether, this pen‑meter helps you maintain reliable water quality with minimal effort.
Usage & Maintenance Tips
- Rinse the probe in clean water before each use to avoid residual contamination.
- Insert the pen into the water sample, wait for the reading to stabilise, then press “HOLD” if you need to record the value.
- Store the pen dry and shut it off when not in use — the auto‑off helps prolong battery life.
- Replace batteries when the screen dims or fails to hold a stable reading.
- For accurate long‑term monitoring, keep a log of readings and check if unexpected spikes occur — that often signals filter, softener, or RO membrane issues.


Shipping and Delivery
Monster Mechanical delivers nationwide across South Africa. Orders are processed once payment is confirmed, and dispatch timing depends on product type, stock availability and whether your system is built to order.
Delivery Information
- In-stock components and smaller items are usually dispatched within 1–3 business days.
- Larger RO systems, custom assemblies and project orders may require additional build or handling time before dispatch.
- Delivery times vary by destination and courier service, with major centres typically faster than regional or outlying areas.
For bulky equipment, installation-related deliveries or urgent requirements, please contact our team before ordering so we can confirm lead times, freight options and the best delivery solution for your location.



