Industrial dust removal systems (such as bag filters and electrostatic precipitators) Current transformer CT require monitoring and control of key electrical parameters during operation to ensure effective removal and equipment safety.

Current transformer ct, a commonly used electrical sensor, are used for measurement, protection, and control. In dust removal systems, CTs isolate high voltages and currents, providing a safe measurement method for personnel and real-time current data for power control systems.

Industrial dust removal systems involve multiple electrical devices and control links. Current transformer ct play a monitoring and control role in the system :

It is mainly reflected in the following aspects

1.for induced draft fans and forced draft fans 

Bag filters and electrostatic precipitators require high-power fans to extract dust-laden gases.

Installing a current transformer ct in the fan motor circuit enables real-time monitoring of the fan motor’s operating current.

This helps determine whether the fan is operating normally and whether the load is abnormal.

Therefore , environmental regulators monitor changes in the dust collection fan’s current to determine whether the dust collection facility is operating as required.

2.Electrostatic precipitator high-voltage power supply monitoring

Electrostatic precipitators rely on a high-voltage electric field to collect dust. The primary current of the high-voltage power supply is often as high as hundreds of amperes.

This current must be converted to a standard signal (such as 5A or 1A ) via a current transformer ct for data acquisition by the control unit.

The control system simultaneously monitors parameters such as primary current and voltage, as well as secondary current and voltage , to adjust the ESP power output and implement spark discharge detection and flashover control .

The primary current signal provided by the current transformer can be used to determine the transformer load, detect overcurrent faults, and protect the power supply equipment.

3.Pulse Cleaning Control Systems

Current transformers also have applications in compressed air pulse cleaning systems for bag filters.

For example, installing a current transformer in the drive circuit of an electromagnetic pulse valve can monitor the power supply to each solenoid valve coil , thereby determining whether the pulse jet is operating successfully.

If any pulse valve coil current is abnormal (no current or current overload ), the control system will promptly issue an alarm .

4.The operating status of auxiliary drive equipment in dust removal systems (such as the dust removal unit’s motor and vibrating motor) can also be monitored using current transformer ct. When these devices malfunction, their current characteristics change significantly.

The feedback from the current transformers can be used to trigger protection measures or alarms, preventing further escalation of the fault.

For example, CT monitoring can help promptly detect blockages in the screw conveyor motor of a dust removal system and initiate shutdown for protection.

In the above application scenarios, the main purpose of the current transformer is to monitor the operating status and provide protection control basis:

collecting current records under normal circumstances and triggering protection mechanisms under abnormal circumstances.

The use of current transformers to achieve motor protection mainly includes the following aspects:

1.The fan motor is the power equipment of the dust removal system and its reliable operation is related to the dust removal effect.

If the overload, stall (stuck) or phase loss during motor operation is not handled in time, it may burn out the motor or cause a safety accident.

As a detection device for the motor protection device , the current transformer can effectively improve the sensitivity and stability of the protection. This is mainly reflected in the following aspects.

2.Overload protection

When a motor’s current exceeds its rated value for a prolonged period due to excessive load, the secondary current output by the current transformer increases.

Thermal relays rely on the bending of a bimetallic strip due to heat, which can be unstable and easily affected by the environment.

Current transformers, on the other hand, can more accurately sense overload currents and achieve inverse-time tripping through their time-delay characteristics, simulating the motor’s thermal model.

Statistics show that the vast majority of asynchronous motor failures are caused by stator winding overheating and damage, while phase failure is relatively rare .

Thermal relays offer significant uncertainty in protecting against phase failure overloads , while protectors based on CT detection can effectively identify such overloads, thereby more effectively preventing motor overheating and burnout.

3.Stalled-rotor/short-circuit protection

When a motor stalls, the current instantly increases to its rated value.

Short-circuit faults generate extremely high currents.

CT can quickly sense the sudden current surge and, in conjunction with relays or electronic protection devices, trip the circuit .

Electronic overcurrent relays use CT to detect current.

When the current exceeds the rated value , they disconnect the circuit, preventing equipment damage caused by short circuits or stalls.

Severe short-circuits are generally protected by instantaneous tripping.

Stalled-rotor faults can be protected by short-delayed rapid tripping.

Symmetrical overloads utilize inverse-time characteristics. The current signal provided by the CT forms the basis for these protection criteria.

4.Phase loss and imbalance protection

A phase loss or three-phase current imbalance in a three-phase motor can cause stator winding overheating.

Thermal relays have insufficient phase loss protection and cannot reliably detect phase loss .

Motor protectors use three-phase current transformers to detect the three-phase current.

If any phase current is too low or the three-phase amplitudes are asymmetrical, they detect a phase loss or imbalance and initiate a trip command.

Phase loss protection using CT detection can effectively reduce motor burnout, especially in high-temperature and dusty environments .

Compay：HEYI Electrical Co., Ltd.

Brand: HEYI/ASCT

Contact: Bethy

E-mail: heyi@heyiele.com             

Tel: 86-13968747975

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