Product details
Compact Process pH Sensor — Analog mV Output
The InstroDirect IDH-100T Compact Process pH Sensor – 12mm Body is a compact 12mm-body industrial pH electrode designed for general process water, cooling tower, and wastewater monitoring. Standard glass bulb with double-junction Ag/AgCl reference and integrated Pt1000 temperature sensor. Analog mV output pairs with any pH transmitter.
Technical Specifications
| Parameter | Specification |
|---|---|
| Measuring range | 0 – 12 pH |
| Temperature range | 0 – 60 °C |
| Pressure range | ≤ 0.2 MPa |
| Temperature compensation | NTC10K, NTC30K, NTC2.252K, PT100, PT1000 can be customised |
| Response time | ≤ 10 s |
| Factory slope | ≥ 95% |
| Zero potential | ± 10 mV |
| Reference type | Industrial reference |
| Reference material | Ag/AgCl |
| Reference electrolyte | Industrial Gel |
| Salt Bridge | Ceramic sand core |
| Membrane resistance | < 80 MΩ |
| Mounting Thread | Upper and lower 3/4″ NPT pipe threads |
| Shell material | PP |
| Length | 170 mm |
| Cable Connection | Integrated direct connection |
Typical Australian Applications
- Cooling tower pH monitoring
- Potable water neutralisation control
- Wastewater treatment plant (WWTP) aeration
- Chlorine dosing feedback
- Industrial process water
Why Engineers Choose the IDH-100T
- Glass bulb is the industry-standard reference for regulatory pH measurement
- Double-junction reference extends life in sulphide and chloride-rich wastewater
- Pt1000 ATC built in — no separate RTD lead required
- PG13.5 thread fits any standard pH pipe boss or flow cell
- Economical workhorse electrode for general process duties
Installation & Calibration
Install through a 3/4″ NPT pipe boss with the pH bulb fully submerged. Calibrate two-point using pH 7 and pH 4 (acid process) or pH 7 and pH 10 (alkaline process) buffers. Typical recalibration interval is 1–3 months depending on fouling load.
Frequently Asked Questions
What transmitter does this work with?
Any standard pH transmitter accepting high-impedance mV input: Yokogawa FLXA21, Endress+Hauser Liquiline CM14, HACH pHD, or generic 4–20 mA pH transmitters. For digital RS485 integration choose the IDH-100P Pro variant.
How long does the electrode last?
Typical life is 12–24 months in clean water and 6–12 months in dirty wastewater. Life is shortened by very high temperatures, chlorine, and organic solvents.
Australian Technical Support & On-Site Calibration
- Australian field engineers with 20+ years of industrial automation experience — phone and email support during AEST business hours.
- On-site pH calibration service across QLD, NSW, VIC — two-point buffer calibration (pH 4 / 7 / 10) with formal calibration certificate.
- Sensor health diagnostics — slope, offset, glass impedance, and reference junction checks.
- Replacement electrodes and buffer solutions available from InstroDirect’s broader water-analysis range.
Why InstroDirect vs Endress+Hauser or HACH in Australia
InstroDirect supplies the same grade of pH sensor that Australian councils, WWTP integrators, pharma plants, and food & beverage operators specify from Endress+Hauser (CPS11D, CPS31D, CPS41D, CPS71D) and HACH (pHD, Differential pH) — at a significantly lower landed cost and without vendor lock-in.
| Factor | InstroDirect | Endress+Hauser / HACH |
|---|---|---|
| Digital protocol | Open RS485 Modbus RTU — integrates with Allen-Bradley, Siemens, Schneider, Beckhoff, or any SCADA | Proprietary Memosens / HACH SC — locked to the vendor’s transmitter |
| Technical support | Australian field engineers with 20+ years automation experience | Offshore ticket queue or authorised distributor |
| On-site calibration | InstroDirect service across QLD, NSW, VIC with formal certificate | Third-party authorised service network, longer turnaround |
| Price | Parallel-import, no distributor margin stack — typically 30–50% below equivalent E+H / HACH pricing | Premium brand with distributor markup |
| Replacement parts | Standard glass-bulb and reference cartridges | Proprietary Memosens head, tied to the brand |
Moving away from Memosens or SC digital protocols frees you to mix and match sensors with any Modbus-capable transmitter or PLC. InstroDirect pH electrodes drop straight into an existing control system without a new proprietary transmitter.
Request a Trade Quote
Panel builders, integrators, council water departments, and pharma/process teams get volume trade pricing. Submit a quote request and we’ll respond within one business day.
