KJ GROUP ZDF-5227CX Dual-Sensor Composite Vacuum Gauge
| Brand | KJ GROUP |
|---|---|
| Origin | Liaoning, China |
| Manufacturer Type | Authorized Distributor |
| Country of Origin | China |
| Model | ZDF-5227CX |
| Price | Upon Request |
| Measurement Range | 1.0×10⁵ to 1×10⁻⁵ Pa (Effective Range: 3×10³ to 1×10⁻⁵ Pa) |
| Compatible Gauges | ZJ-52T (thermocouple), ZJ-27 (Pirani) |
| Measurement Channels | 4 independent channels |
| Display | 4 five-digit LED windows with scientific notation (e.g., 1.2E−1 = 1.2×10⁻¹ Pa) |
| Control Outputs | 4 relay channels (expandable to 6) |
| Control Modes | Point control & zone control with power-loss memory |
| Relay Load Rating | AC 220 V / 3 A or DC 28 V / 10 A |
| Power Supply | AC 220 V ±10 %, 50 Hz, 45 W |
| Dimensions (W×H×D) | 480 × 88 × 260 mm |
| Cutout Size | 440 × 80 mm |
| Weight | ~4 kg |
| Analog Output Options | 0–5 V / 4–20 mA |
| Communication Interfaces | RS-232 / RS-485 |
| Gauge Cable Length | Standard 5 m (custom lengths available) |
| Gauge Flange Options | ZJ-52T/ZJ-27 compatible with glass, metal direct-insert, DN16/25/35 CF, DN10/16/25/40 KF |
Overview
The KJ GROUP ZDF-5227CX Dual-Sensor Composite Vacuum Gauge is a microprocessor-controlled vacuum measurement and process control instrument engineered for high-reliability operation across wide dynamic pressure ranges in industrial vacuum systems. It integrates two independent sensor input paths—one for ZJ-52T thermocouple gauges and one for ZJ-27 Pirani gauges—enabling simultaneous, real-time monitoring and closed-loop control of up to four distinct vacuum zones. Unlike single-principle gauges, the composite architecture leverages thermal conductivity (Pirani) and thermoelectric voltage (thermocouple) principles to deliver continuous coverage from atmospheric pressure (1.0×10⁵ Pa) down to high vacuum (1×10⁻⁵ Pa), with optimal accuracy maintained across the effective range of 3×10³ to 1×10⁻⁵ Pa. The embedded 8-bit microcontroller performs on-board non-linear compensation and temperature-corrected calibration, minimizing drift and improving long-term stability. Designed for integration into semiconductor processing chambers, vacuum coating lines, freeze-dryer control systems, and R&D vacuum furnaces, the ZDF-5227CX meets functional safety requirements for continuous duty under variable thermal load and electromagnetic noise environments.
Key Features
- Dual-sensor architecture supporting concurrent ZJ-52T (thermocouple) and ZJ-27 (Pirani) gauge inputs for seamless transition across low-, medium-, and high-vacuum regimes
- Four independent measurement channels with individual zero-offset and span calibration per channel
- Four dedicated LED display windows using scientific notation (e.g., 2.5E−3), enabling unambiguous interpretation of orders-of-magnitude pressure values
- Four programmable relay outputs with configurable point or zone control logic; expandable to six outputs via optional module
- Non-volatile memory retains setpoints and configuration after power interruption, ensuring process continuity in utility-outage scenarios
- Robust front-panel interface with tactile buttons and status LEDs for local operation without external software dependency
- Comprehensive analog and digital I/O: isolated 0–5 V and 4–20 mA outputs, plus RS-232/RS-485 serial interfaces compliant with Modbus RTU protocol for SCADA integration
Sample Compatibility & Compliance
The ZDF-5227CX is calibrated for use with dry air and nitrogen—standard reference gases per ISO 20487 and ASTM E1915. Its thermally based measurement principle exhibits gas-species dependence; therefore, measurements in hydrogen, helium, argon, or reactive process gases require correction factors or alternative gauge selection (e.g., capacitance manometers for inert gas applications). The instrument complies with IEC 61000-4-2 (ESD immunity), IEC 61000-4-3 (radiated RF immunity), and IEC 61000-4-4 (electrical fast transient burst) standards. While not certified for SIL-rated safety functions, its relay output architecture supports fail-safe wiring practices in accordance with IEC 61508. For regulated environments (e.g., pharmaceutical lyophilization or medical device manufacturing), the device supports audit-trail-capable data logging when paired with KJ GROUP’s optional PC-based supervision software—compatible with FDA 21 CFR Part 11 electronic record requirements when deployed with appropriate system validation protocols.
Software & Data Management
The ZDF-5227CX operates autonomously but supports bidirectional communication via RS-232 or RS-485. KJ GROUP provides a Windows-compatible configuration utility (v3.2+) that enables remote calibration coefficient upload, control setpoint programming, alarm threshold definition, and real-time waveform capture at user-defined sampling intervals (100 ms to 10 s). Logged data exports to CSV format with timestamping and channel identification, facilitating traceability in GLP/GMP workflows. The analog outputs (0–5 V / 4–20 mA) are factory-calibrated to full-scale pressure ranges and maintain linearity within ±0.5 % FS over 0–50 °C ambient. Optional firmware updates address field-reported edge cases—including thermal hysteresis compensation during rapid pump-down cycles—and are distributed through KJ GROUP’s secure customer portal.
Applications
- Process monitoring and interlock control in physical vapor deposition (PVD) and chemical vapor deposition (CVD) systems
- Vacuum integrity verification in sterilization autoclaves and pharmaceutical freeze dryers
- Chamber evacuation sequencing in electron microscopy sample preparation stations
- Leak detection support via pressure-rise rate analysis in sealed enclosure testing
- Quality assurance in vacuum brazing and sintering furnaces where pressure ramp profiles impact metallurgical outcomes
- Educational laboratory use for vacuum physics instruction, including mean free path calculation and Knudsen number estimation
FAQ
What gases can the ZDF-5227CX accurately measure?
It is factory-calibrated for dry air and nitrogen. Measurements in other gases require application-specific correction factors due to thermal conductivity and molecular weight dependencies.
Can the ZDF-5227CX operate without a connected PC?
Yes—the unit functions fully standalone with local keypad control, LED display, and relay outputs. PC connectivity is optional for configuration, logging, or system integration.
Is the 1×10⁻⁵ Pa lower limit achievable with all gauge types?
No. The ZJ-27 Pirani gauge contributes reliable readings down to ~1×10⁻⁴ Pa; the extended 1×10⁻⁵ Pa range relies on extrapolated behavior and should be validated with a calibrated cold cathode or Bayard-Alpert gauge for critical high-vacuum applications.
Does the device support NIST-traceable calibration?
KJ GROUP provides factory calibration certificates referencing national metrology institute standards. Field recalibration requires ZJ-series reference gauges traceable to NIST or equivalent NMIs.
How is electromagnetic interference mitigated in industrial settings?
The unit incorporates ferrite-core filtered power input, opto-isolated relay drivers, and twisted-pair shielded cabling recommendations for gauge and signal lines—reducing common-mode noise susceptibility per IEC 61326-1 Class A requirements.

