Timepower TP121 Online Conductivity Analyzer
| Brand | Timepower |
|---|---|
| Origin | Beijing, China |
| Manufacturer | Timepower Measurement & Control Co., Ltd. |
| Model | TP121 |
| Output Signals | 0–10 mA / 0–20 mA / 4–20 mA (selectable) |
| Temperature Compensation | Manual or Automatic (Pt1000 sensor, 0–60 °C) |
| Measurement Ranges | (0.01–20.00) µS/cm (K=0.01), (0.1–200.0) µS/cm (K=0.1), (2–2000) µS/cm (K=1.0), (20 µS/cm–20 mS/cm) (K=10.0) |
| Accuracy | ±2.5% F.S. |
| Resolution | 0.01 µS/cm |
| Repeatability | <1% |
| Display | 128×64 dot-matrix LCD with bilingual English/Chinese interface |
| Operating Temp. | 5–60 °C (sample), 5–45 °C (ambient) |
| Humidity | ≤90% RH (non-condensing) |
| Storage Temp. | −25–55 °C |
| Power Supply | AC 85–265 V or 24 VDC |
| Power Consumption | ≤15 W |
| Enclosure Rating | IP65 |
| Mounting | Panel-mount / wall-mount / rack-mount |
| Electrode Mounting | Flow-through / immersion / flanged / in-line pipe |
| Data Storage | User-configurable logging with historical trend display |
| Relay Outputs | 2 SPST (AC 220 V / 3 A or DC 30 V / 3 A) |
| Memory Retention | >10 years after power loss |
| Dimensions | 98 × 130 × 98 mm (W×H×D) |
| Cut-out | 94 × 94 mm |
| Weight | 0.5 kg |
Overview
The Timepower TP121 Online Conductivity Analyzer is a microprocessor-based industrial process instrument engineered for continuous, real-time monitoring of electrical conductivity in aqueous solutions across diverse production and treatment environments. It operates on the principle of two-electrode or four-electrode conductometric measurement—applying an alternating current across a pair of electrodes immersed in the sample medium and calculating conductivity (σ) from the measured conductance (G) and cell constant (K): σ = G × K. The analyzer supports interchangeable conductivity cells with standardized cell constants (K = 0.01, 0.1, 1.0, and 10.0 cm−1), enabling precise range selection for applications spanning ultrapure water monitoring (e.g., pharmaceutical WFI systems), boiler feedwater control, wastewater effluent compliance, and chemical dosing verification. Its robust architecture integrates high-impedance isolation circuitry and surface-mount technology to ensure long-term stability under electrically noisy plant conditions.
Key Features
- Bilingual 128×64 dot-matrix LCD with intuitive menu navigation—switchable between English and Chinese without firmware reset
- Auto-ranging capability across four decades (0.01 µS/cm to 20 mS/cm) via user-selectable cell constant configuration
- Dual-mode temperature compensation using integrated Pt1000 RTD sensor (0–60 °C), supporting both automatic and manual offset adjustment per ISO 7888 and ASTM D1125 standards
- High-immunity analog output (4–20 mA default, configurable to 0–10 mA or 0–20 mA) with galvanic isolation (>1500 VAC) for noise rejection in distributed control systems
- Two programmable relay outputs (SPST, 3 A resistive load) for alarm staging, pump interlock, or valve actuation—each independently assignable to conductivity thresholds or rate-of-change events
- Onboard data logging with non-volatile memory retaining >10 years of timestamped readings; accessible via scrollable history curve on display
- IP65-rated front panel enclosure suitable for indoor industrial enclosures and outdoor NEMA-type housings with optional sunshade
Sample Compatibility & Compliance
The TP121 is compatible with standard industrial conductivity sensors employing stainless steel, titanium, or graphite electrodes—configured for flow-through cells (for pressurized pipelines), immersion probes (for open tanks), flanged assemblies (for sanitary or high-pressure vessels), or direct in-line mounting. It meets electromagnetic compatibility requirements per IEC 61326-1 (industrial environment) and conforms to safety standards IEC 61010-1 for electrical equipment used in measurement, control, and laboratory applications. While not certified for intrinsic safety (e.g., ATEX/IECEx), its 24 VDC option enables integration into hazardous-area barrier systems. For regulated industries—including pharmaceuticals, food & beverage, and power generation—the device supports audit-ready operation when paired with external SCADA/HMI platforms compliant with FDA 21 CFR Part 11 (electronic records/signatures) and EU Annex 11 (computerized system validation).
Software & Data Management
No proprietary PC software is required for basic commissioning or calibration; all configuration—including relay setpoints, temperature coefficient (β), damping time (0–30 s), and display units (µS/cm, mS/cm, or % NaCl)—is performed locally via membrane keypad. However, time-stamped conductivity logs and trend snapshots can be exported manually via RS-232 serial port (optional module) for integration into LIMS or MES platforms. The analyzer maintains full GLP/GMP traceability through internal event logging: each calibration, relay activation, or parameter change is timestamped and stored alongside operator ID (if enabled via external authentication gateway). Data retention remains intact during power interruption due to supercapacitor-backed memory architecture.
Applications
- Power plant cycle chemistry: condensate polishing, demineralizer effluent, and steam drum water quality surveillance
- Pharmaceutical water systems: PW, WFI, and pure steam condensate conductivity verification per USP and EP 2.2.38
- Food & beverage processing: CIP rinse water conductivity profiling, brine concentration control, and syrup dilution monitoring
- Municipal and industrial wastewater: influent/effluent salinity screening, membrane fouling detection, and desalination reject stream management
- Chemical manufacturing: acid/base titration endpoint tracking, electrolyte bath concentration control, and catalyst solution monitoring
FAQ
What cell constant options are supported, and how do I select the appropriate one?
The TP121 accepts probes with K = 0.01, 0.1, 1.0, or 10.0 cm−1. Selection depends on expected conductivity: K = 0.01 for ultrapure water (10 mS/cm).
Does the analyzer support linearization for non-aqueous or high-ionic-strength solutions?
No—it assumes ideal electrolyte behavior per Kohlrausch’s law and does not implement custom conductivity vs. concentration polynomials. For non-standard media, empirical calibration against reference solutions is recommended.
Can the TP121 be integrated into a Modbus RTU network?
Not natively—the standard unit lacks built-in Modbus. An optional RS-485 expansion module (sold separately) enables Modbus RTU slave functionality with configurable slave ID and baud rate (9600–115200 bps).
Is temperature compensation disabled by default?
No—automatic Pt1000-based compensation is active upon power-up. Manual compensation mode allows fixed temperature input (e.g., for ambient-corrected lab-grade comparisons) but disables real-time thermal correction.
What maintenance intervals are recommended for the conductivity cell?
Electrode cleaning frequency depends on fouling risk: weekly for wastewater, quarterly for boiler feedwater, and annually for ultrapure water loops. Calibration verification should occur before critical batches or at least every 30 days in GMP environments.

