Differential Pressure Controller High Low Alarm Digital Display Dust Collector

Differential Pressure Controller High Low Alarm Digital Display Dust Collector

Product Overview

The differential pressure controller is a panel-mounted instrument that continuously measures the pressure drop (ΔP) across filter media in baghouse and cartridge dust collectors. It displays the value on a bright digital screen and provides independent high and low limit alarms with relay outputs. When ΔP rises to the high setpoint, it signals that filter bags are loaded and pulse-jet cleaning is due. When ΔP drops suddenly, it detects a torn bag or failed filter before emissions exceed limits. The controller replaces unreliable mechanical gauges with a stable, temperature-compensated silicon piezoresistive sensor. Optional 4–20 mA and RS485 Modbus RTU outputs allow connection to PLC, DCS, or BMS for remote monitoring and logging. It is designed for simple front-panel setup with field zeroing, making it easy for maintenance teams to use without special training. Suitable for all dust collection systems, this single instrument is the most cost-effective safeguard for filter performance and regulatory compliance.

Cause: Guesswork Leads to Downtime, Wasted Energy, and Emissions

Maintenance teams face recurring problems without reliable ΔP monitoring:

• Readings jump or false alarms due to blocked impulse lines or electrical noise from VFDs.
• Mechanical gauge needles stick and are hard to read in dark, dusty locations; they have no alarm function.
• Torn bags are discovered too late, after emissions exceed limits and the plant faces fines.
• Filter bags are replaced too early or too late because there is no continuous data to base the decision on.
• Operators struggle with confusing setpoint programming, leading to mistakes.
• Control rooms cannot see pressure trends because no signal goes to the PLC or BMS.

These problems result in higher fan energy, premature bag replacement, production downtime, and in combustible dust applications, increased fire or explosion risk.

Solution: Stable Digital Monitoring with High and Low Alarms

This controller eliminates guesswork. The high-limit relay can trigger pulse-jet cleaning automatically or activate an alarm beacon. The low-limit relay detects sudden ΔP drops caused by bag failure and shuts down the system immediately. A bright digital display gives a clear reading day and night. Field zeroing and signal filtering reject interference from dust, condensate, and electrical noise. The optional 4–20 mA and RS485 outputs provide continuous data to your control system. Setup is quick with simple front-panel buttons, and the high and low setpoints are independent for maximum flexibility.

Specifications

Application

• Baghouse and pulse-jet dust collectors in cement, steel, minerals, and wood processing.
• Cartridge dust collectors for welding fume, food, and pharmaceutical applications.
• Cleanrooms and laboratories monitoring room-to-room differential pressure.
• HVAC and AHU filter status monitoring.
• Paint spray booths and powder coating rooms.
• Boiler and flue gas dedusting systems.
• Pneumatic conveying and silo vent filters.

How It Works

Two pressure taps — one on the dirty inlet side and one on the clean outlet side — are connected to the controller. The sensor measures the difference between the two pressures. When filter media is clean, ΔP is low. As dust builds a cake, ΔP rises. When ΔP reaches the high setpoint, the relay closes and triggers cleaning or an alarm. If a bag tears, ΔP drops suddenly below the low setpoint, and the second relay activates to alert operators or stop the fan.

How To Choose

1. Determine your normal operating ΔP. Select a range where normal operation is 50–70% of full scale.
2. Choose the power supply: 9-24 VDC.
3. Decide on outputs: relay only, or add 4–20 mA and RS485 for remote monitoring.
4. Confirm the pressure connection type and enclosure requirements for your installation.

Contact us with your normal and maximum ΔP, and we will recommend the correct range within 24 hours.

FAQ

1. Can this controller trigger pulse-jet cleaning automatically?
   Yes. The high-limit relay can be wired to your cleaning controller to start cleaning only when ΔP requires it, saving compressed air and extending bag life.
2. How do I prevent false alarms?
   Most false alarms come from blocked or moisture-filled impulse lines. Slope the tubing downward from the taps, keep lines clean, and use shielded cable away from VFDs. Set the high limit with adequate margin above normal operation.
3. What range do I need?
   For most baghouses, 0–1500 Pa or 0–2000 Pa is typical. For fine cartridge filters, 0–3000 Pa may be needed. Provide your normal ΔP and we will confirm the best range.
4. Is there a 24 VDC version with 4–20 mA output?
   Yes. 9- 24 VDC power options are available, along with optional isolated 4–20 mA and RS485 Modbus RTU outputs.
5. How often should I recalibrate?
   We recommend field zeroing after installation and full recalibration every 6–12 months, depending on process conditions.
6. What does a sudden ΔP drop indicate?
   A sudden drop usually means a filter bag has torn or a seam has opened. The low-limit alarm detects this immediately, allowing you to shut down before emissions exceed limits.
7. How do I order?
   Tell us your normal and maximum differential pressure, power supply, outputs needed, and quantity. We will quote within 24 hours. OEM/ODM welcome.