LEAK ALERT 75
Product Descriptions
The PCME LEAK ALERT 75 is a TUV approved Filter Leak Monitor suited to filter control applications after fabric filter type (baghouse) dust arrestment plant. The instrument is certified according to BlmSchV 27 class 3 (EN 15859)* and offers a rugged and reliable filter leak monitoring capability for plants requiring license, and is similarly suitable for meeting US ASTM D7392-07 for Bag Leak Detectors. Options for ATEX / IECEx category 1/2/3 for Dust Zones 20, 21, 22 and integrated or stand-alone control unit add to the system flexibility.
* equivalent to MCERTS ‘Performance Standards for Automated Dust Arrestment-Plant Monitors’ version 1, class 3 PM-CEM (August 2010)
Using ENVEA UK’s patented ElectroDynamic™ Probe Electrification technology, the instrument extracts a specific frequency band from the induced AC current signature and filters out the DC current caused by particle collisions. The technology outperforms conventional DC triboelectric systems and alternative AC systems by extending the velocity range over which the instrument has no cross sensitivity to changing velocity, and is unaffected by contamination of the sensor rod eliminating concerns of signal drift.
• High quality leak response with sufficient dynamic range and time response to track emissions from single and multi-compartment pulse cleaned bagfilters
• System self-checks to validate measurement integrity including automatic Zero and Span checking
• ATEX / IECEx category 1D/2D/3D for dust zones 20, 21, 22
• Insulated sensor rod option for unmatched performance in high humidity applications
• Powerful integrated user interface with keypad and display for intuitive instrument set-up
• 0-100% or user scalable display, of assistance to plant operators wishing to manually scale the display to an approximate known dust level
Durable Sensor Options for Varied Applications
Standard sensors for probe electrification instruments will only perform under certain process conditions. For example, conductive particulate matter, high levels of humidity and explosive atmospheres will present different challenges to probe electrification technologies, can cause errors in measurement or potentially damage the instrument. The PCME LEAK ALERT 75 offers a range of rugged, durable sensor options to address challenging stack conditions:
• Patented insulated sensing rod option, significantly increases the maintenance interval required for probe electrification type instruments used in humid flue gases or where conductive dusts are present, and provides unrivalled performance in process drier applications
• ATEX/IECEx certified for dust zones 20, 21, 22
Automatic Functionality and Quality Assurance Checks
The PCME LEAK ALERT 75 features comprehensive self checks to ensure regulatory compliance and to provide plant operators with pre-emptive warning of potential sensor issue to allow preventative maintenance scheduling, lower process down times and confidence of data integrity.
• Manual or automated zero and reference drift detection checks to ensure any electronic and signal measurement malfunction is automatically detected. This Quality Assurance Feature is required by European and ASTM (US) performance standards for Filter Leak Monitors.
• Probe rod short circuit check enables operator to know when the sensing rod may be electrically shorted to the stack and avoid associated errors
Advanced Signal Processing and Diagnostics
Accurate emission measurement with rapid dynamic ranging allows plant operators to locate the position of leaking bags in multi-compartment bag filters. When integrated with ENVEA UK’s Predict PC software this provides ultimate arrestment plant fault finding capability:
• Rapid dynamic ranging of 10,000:1 permits bag cleaning pulses to be accurately monitored while maintaining high accuracy in background emission monitoring. Sufficient dynamic ranging is provided to follow “on-line” and “off-line” bag cleaning cycles for predictive filter failure and faulty bag location detection
• Rolling (‘walking window’) digital average calculations for accurate emission measurement
Process Conditions
The PCME LEAK ALERT 75 is suitable for:
• Stacks after bag filters, cartridge filters, cyclones
• Constant or variable velocities within range 8-20m/s (typical bagfilter velocity ranges), constant velocity required outside this range
• After process driers
• Explosive atmosphere zones 20, 21 and 22
• Non-condensing / dry flue gases*
• Not suitable for electrostatic precipitators or applications with water droplets*
* For wet / condensing flue gas applications see PCME STACK 181 WS
Typical Applications
The PCME LEAK ALERT 75 is used to monitor emissions from the following types of processes:
• Quarrying (eg Rotary Dryers, Roller Mills)
• Carbon Black filter plant
• HEPA filters (eg pharmaceutical / biomedical plant)
• Coal Mill / Cement Mill/ Cement Kiln arrestment plant
• Humid applications eg Dryers, Calcinators
• Wood cutting & chipping plant
| APPROVALS | TUV ‘Filter Leak Monitor’ according to BlmSchV 27 (EN 15859), |
| equivalent to MCERTS ‘Performance Standards for Automated Dust Arrestment-Plant Monitors’ version 1, | |
| class 3 PM-CEM (August 2010) | |
| MEASUREMENT CAPABILITY | 0-500 mg/m3 (Leak monitoring) |
| LONG TERM ZERO DRIFT | < 0.1 mg/m3 |
| AIR PURGE REQUIREMENT | May be required on some applications (consult PCME), 5-10 litres/min of dry, clean, oil free instrument air |
| INSPECTION FREQUENCY | 6 months (dependant on application) |
| STACK DIAMETERS | 100mm – 6m (flow profile dependant on large stacks) |
| STACK TEMPERATURES | 0-250°C (option to 400°C) |
| COMBINED SENSOR & | • 316 stainless, or fully insulated PTFE coated option for conductive dust or |
| CONTROL UNIT | humid flue gas application (Sensor Probe) |
| • IP65 die-cast aluminium (Enclosure) | |
| • Stack temperature ranges 0-250°C, 0-400°C | |
| • Alarming: Local and via 2 x relay outputs | |
| • RS232/RS485 data output option for Modbus networking, PC interface | |
| • 1 x 4-20mA output (scalable) | |
| • Power: 100-240VAC or 24VDC | |
| • User setup: 4 digit display and internal or external keypad | |
| • ATEX/IECEx category 1D/2D/3D for dust zones 20, 21, 22 | |
| • Air Filter and Regulator assembly for plant instrument air | |
| (air purge typically not required for most applications) | |
| • Optional Bag Pulse Display Module, for visual tracking of multi-chamber baghouse cleaning cycles |
