CI-PC986 Wide-Range Oxygen Transmitter — Measure 1ppm to 25% O₂ in One Unit

"How many ppm of oxygen is in this line right now?" — Why wide-range measurement matters

Oxygen (O₂) means very different things depending on the process. In air separation and high-purity gas lines, ppm-level residual oxygen in the product gas signals a purity defect, while in combustion and reaction processes, percent-level oxygen determines efficiency and safety. The problem is that most oxygen analyzers are split into ppm-only or %-only models, making it hard to cover both ranges at one site.

CHANG AI's CI-PC986 wide-range oxygen transmitter was designed to bridge exactly this gap. The CI-PC986 uses an electrochemical digital sensor to measure from 1ppm to 25% in a single unit, solving both ppm-level trace oxygen monitoring and %-level concentration management at once. Why do air separation and gas production sites choose this transmitter? The answer lies in its sensor principle and pressure-protection design.

Electrochemical oxygen sensor — Measurement principle

The CI-PC986 is equipped with an electrochemical oxygen sensor. Measurement proceeds in the following steps.

1. The automatic flow-control function delivers the sample gas to the sensor measurement chamber (test chamber) at a constant flow rate.
2. Oxygen molecules trigger an electrochemical reaction at the sensor electrode, and the resulting current is proportional to the oxygen concentration.
3. A built-in pressure compensation algorithm removes errors caused by pressure fluctuations, correcting the reading to the true concentration.
4. The microprocessor digitally processes the signal (zero/span correction and linearization), displays the concentration, and outputs it via 4-20mA and RS485.

Electrochemical sensors offer excellent sensitivity at ppm-level low concentrations while still enabling wide-range measurement, making them inherently well suited to covering trace through high concentrations in one unit. (Source: CHANG AI CI-PC986(K2) official operation manual and product datasheet)

Four standout strengths of the CI-PC986

① Wide-range measurement — ppm to 25% in one unit

General oxygen analyzers are fixed to a ppm-only or %-only range, so a separate device is needed when the process range changes.

The CI-PC986 is different. It measures the wide range of 0~10/100/1000ppm·1%·25.00% O₂ with a single transmitter, handling ppm-level purity management and %-level concentration monitoring at once.

② Digital sensor — No calibration after field replacement

Analog sensors require recalibration every time they are replaced, lengthening maintenance time.

The CI-PC986 uses a digital sensor, letting users replace the sensor directly in the field, and no separate calibration is required after replacement. Downtime is shorter and operation is simpler.

③ Pressure compensation & over-pressure protection — Stability in positive-pressure processes

Oxygen sensors are sensitive to pressure fluctuations, and excessive pressure damages the sensor.

The CI-PC986 removes pressure-induced errors with its pressure compensation function, and with its over-pressure protection function it automatically shuts off the gas path when the internal test-chamber pressure exceeds the set range. Combined with voltage regulation and automatic flow control, it is optimized for positive-pressure conditions.

④ Process automation integration — Both signal and communication supported

It supports 4-20mA (standard)/0-20mA (option) analog output and RS485 communication, connecting directly to PLC, DCS, and HMI. Its transmitter form factor makes it easy to integrate into distribution and instrumentation panels, and an optional 4.3-inch color touchscreen handheld unit enables on-site setup and checks.

General oxygen analyzer vs. CI-PC986 wide-range oxygen transmitter

Industries where the CI-PC986 is essential

1. Air separation industry — Precise monitoring of oxygen concentration in product gas during oxygen/nitrogen/argon production
2. Gas production & manufacturing inspection — Real-time measurement of oxygen concentration in gas shipped from production lines
3. Food production processes — Managing residual oxygen in packaging/filling to secure quality and shelf life
4. Petrochemical processes — Monitoring oxygen concentration during reaction/refining for safety and quality control
5. Inert-gas & hydrocarbon processes — Detecting trace oxygen in nitrogen/helium/argon/hydrocarbon background gases

CHANG AI's wide-range oxygen transmitter — CI-PC986

📌 CI-PC986 — Wide-range oxygen transmitter

The CI-PC986 is a transmitter-type online oxygen analyzer installed securely in a metal enclosure. It measures samples via automatic flow control, and with a Φ6.5 quick-fitting inlet and an anti-clogging powder-metallurgy outlet head, it is suited to positive-pressure processes. It is compact at about 1.3kg net weight.

📊 CI-PC986 technical specifications

※ Source: CHANG AI CI-PC986 product page specification table and CI-PC986(K2) official operation manual. Recommended calibration interval is once per year. Specifications may vary by configuration and options.

Why the CI-PC986 is the right answer for wide-range oxygen measurement

Typical oxygen measurement equipment hits limits in the following situations.

• Split measurement ranges — Divided into ppm/%-only, requiring two devices at one site
• Pressure fluctuations — Measurement errors from lack of compensation; sensor damage under over-pressure
• Sensor replacement burden — Recalibration on every replacement increases downtime

The CI-PC986 solves these limits simultaneously with an electrochemical wide-range sensor + pressure compensation/over-pressure protection + digital no-calibration sensor + 4-20mA/RS485 integration. A single unit secures measurement range, pressure stability, and process automation all at once.

Closing — Invisible oxygen determines purity and safety

Oxygen is everywhere, but what matters in a process is "exactly how much oxygen is in this line right now." Trace oxygen at the ppm level degrades product purity, and percent-level changes determine process safety. What you cannot measure, you cannot manage.

Are you seeing your process line's oxygen concentration accurately, in a single unit?

CHANG AI's official Korea distributor, RS Korea Co., Ltd., handles sales, repair, calibration, and technical support for the CI-PC986 and all CHANG AI products within Korea. RS Korea operates both its in-house technical team's calibration/maintenance capability and its sales team's on-site visits, processing everything from product selection consulting to sensor replacement and after-sales service through one local channel. If you'd like to learn about other CHANG AI oxygen analyzers, see also our CI-PC562 trace hydrogen analyzer article.