Cape-11A Standard RF Admittance Level Switch
Cape-11A is with modular design, easy for installation and virtually maintenance-free. The external LED light is ideal for long distance observation.
Cape-11A Standard RF Admittance Level Switch can detect capacitance as well as impedance between probe and vessel. It is flexible for various applications while consistently demonstrating immunity to buildup, especially for dust, coal ash and other powdery ashes level control. Cape-11A is with modular design, easy for installation and virtually maintenance-free. The external LED light is ideal for long distance observation.
In Cape-11 RF series, a probe is designed to detect the change of capacitance and impedance between probe and vessel wall to realize level measurement and control. In its electronic unit, reactance between the measurement electrode and the wall of an empty vessel constitutes a balanced bridge circuit which outputs a stable oscillation signal. As the level rises, the measurement electrode is covered by the medium, and reactance between the electrode and the wall of the vessel changes. It causes an imbalance of the bridge circuit and stops the oscillation as a result. A post-circuit is designed to detect the change of output signal from the bridge circuit and generate an alarm signal. In addition, oscillation signal at radio frequency is not only applied to the measurement electrode but also applied to a shield pole through a 1: 1 voltage-follower, so measurement electrode and shield pole have the same electric potential, phase, and frequency, but these two electrodes are insulated from each other. Even if there is medium buildup on the probe, because there is no electric potential difference between measurement electrode and shield pole, the reactance change on shield pole has no effect on the detection of post-circuit. Therefore, only reactance change on the measurement electrode induced by the filled medium between the measurement electrode and the wall of the vessel will be detected by post-circuit. It eliminates the effect of medium buildup on level measurement.
● Excellent flexibility, widely used for the level control of dust, fly ash, coal ash and other powdery ashes.
● With an external dual color LED indicator. Housing with electronic can be rotated to make the orientation of LED indicator convenient for long distance observation.
● Modular design offers high reliability. Easy installation and maintenance.
● Obtained Reliability Test Certifications by the authoritative third party, guaranteed high-performance.
● Long-lasting and high cost-effective ratio.
| Applicable medium | Types of the medium | Coal ash, fly ash, dust |
| Dielectric constant | ≥1.6 | |
| Probe data | Probe length | 250～2000mm |
| Shield length | 90mm/240mm/300mm /590mm or customized | |
| Probe diameter | φ8mm/φ10mm | |
| Materials | Housing | Aluminum alloy |
| Inner housing | Plastic | |
| Probe metallic parts | 304, 316L | |
| Probe insulation parts | PTFE | |
| Power Supply | AC | 85～264V AC |
| DC | 18～30V DC | |
| Power consumption | ≤3W | |
| Switching Delay | When immersed | 1s |
| When laid bare | 1s | |
| Output | Relay | DPDT，8A/250V AC/30V DC |
| Relay delay | 0～30s Continuous adjustable | |
| Installation conditions | Process temperature | -40～250℃ |
| Ambient temperature | -40～70℃ | |
| Storage and transport temperature | -40～80℃ | |
| Certificates and approvals | Ingress Protection | IP66 |
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