Series RPH-260 Probe-type Residual Analyzer

The RPH-260 Probe-type Residual Analyzer from Hydro Instruments provides accurate, reagentless measurement of disinfectant residuals in a wide range of water treatment and industrial applications. With the ability to operate with one or two disinfectant probes, the RPH-260 Residual Analyzer functions as both a free chlorine analyzer and a total chlorine analyzer, delivering continuous monitoring, fast response times, and built-in PID control for superior process management. As an advanced on line analyzer, it provides real-time data and can integrate directly with system controls for optimized performance.

Dual Probe Capability – Supports up to two disinfectant probes, pH electrodes, ORP electrodes, and temperature sensors for flexible monitoring. This allows the RPH-260 to operate as both a free chlorine analyzer and a total chlorine analyzer simultaneously.

Multi-Chemical Detection – Compatible with sensors for:

• Free Chlorine
• Total Chlorine
• Chlorine Dioxide
• Chlorite
• Ozone
• Hydrogen Peroxide
• Peracetic Acid
• Bromine

EPA Compliant – Meets U.S. EPA 40 CFR 141.74 and 40 CFR 141.131, Method 334.0 for on line chlorine analyzers.

Advanced Control Functions – Two independent PID control loops for set point or compound loop control. These can be paired with an automatic valve or an automatic chemical feed valve to regulate disinfectant dosing in real time.

Reliable Flow Cell Design – Gravity-fed, constant-head flow cell with bubble trap and cross-flow diverter for stable readings; pressurized flow cell available for self-cleaning probes.

Easy Operation – Graphical color display (320 x 240 resolution) and straightforward calibration.

Connectivity – Four programmable 4-20 mA outputs, four alarm relays, Modbus RS485 communication, and optional Profibus.

Data Logging – Optional logging capability with removable MicroSD card for compliance and record-keeping.

Durability – NEMA4X (IP66) rated controller suitable for demanding environments.

• Measurement Range (Free Chlorine): 0–0.5, 0–2, 0–5, 0–10, 0–20, or 0–200 PPM
• Measurement Range (Total Chlorine): 0–0.5, 0–2, 0–5, 0–10, or 0–20 PPM
• Response Time (T90): ~30 sec for Free Chlorine; ~2 min for Total Chlorine
• Sample Flow Rate: 4–8 GPH (15–30 L/h) for open flow cell; 12–24 GPH (45–90 L/h) for self-cleaning probe
• Sample Pressure: 5 PSI (0.3 bar) for open flow cell; 15 PSI (1 bar) for pressurized flow cell with cleaning head
• Resolution: 0.01 ppm or ±1% of range
• pH Measurement Range: 4–10 pH (±177 mV)
• ORP Measurement Range: ±2000 mV
• Power Requirements: 100–240 VAC (50/60 Hz) or 12–24 VDC