About fixed electric fire pump control cabinet introduction

Abstract: This paper introduces a new type of fixed electric fire pump control cabinet designed according to the requirements of national standard GBT21208, elaborates its working principle and functional characteristics, and gives the corresponding design block diagram. In the analysis of the traditional fire pump control cabinet defects at the same time put forward the advantages of the new controller.

Overview

Electric fire pump is a widely used in hospitals, shopping malls, office buildings and residential buildings and other high-rise buildings in a water supply device, when an accidental fire, start the fire pump can ensure that the pipe network pressure reaches the fire extinguishing device Requirements, so that the fire be promptly saved. In China's fixed electric fire pump water supply system generally uses one (or more) main pump with one (or more) standby pump mode, and equipped with a dedicated control cabinet to achieve the fire pump control.

Fire pump start and stop, the traditional fire pump control cabinet generally through the secondary circuit in the middle of multiple relays and time relay to achieve, this control method despite the lower cost, but there are a large number of components, wiring complexity, poor versatility And other shortcomings, to the equipment maintenance and upgrading has brought great difficulties. With the improvement of the fire fighting system to the fire pump control cabinet, some control cabinet manufacturers have developed some functions such as dual power switching function, fire pump automatic inspection function and remote control according to the needs of customers. Control cabinets greatly improve the reliability and automation of the fire pump control system, but these new function modules and fire pump control independent of each other, but the two systems are functionally simple integration, and many control cabinets are all functions Modules are provided by different manufacturers, which makes it very difficult to maintain and upgrade these systems with relatively high costs. In addition, the existing fire pump control cabinet are generally based on "Civil Building Fire Extinguishing System Design Code" and "Fire Design Code for High-rise Civil Buildings" (hereinafter referred to as "civilian regulations" and "high regulations") related to the design requirements, due to These norms apply to the entire building fire-fighting system, fire pump control cabinet specific requirements and norms are not perfect, resulting in the current domestic market fire pump control cabinet features a wide range of functions and reliability exist defect.

In order to standardize the design of the electric fire pump control cabinet, proposed by China Electrical Equipment Industry Association, drafted by Shanghai Electric Apparatus Research Institute (Group) Co., Ltd. and Shenzhen Taiyong Technology Co., Ltd. participated in jointly developing a fixed electric fire pump controller Special national standards - "low-voltage switchgear and control equipment - fixed fire pump drive controller" (GBT21208-2007), and in 2007 officially released.

This paper presents a new type of fire pump control cabinet is based on GBT21208-2007, combined with "civil regulations" and "high regulation" of the relevant requirements and design.

2, system composition

The new fire pump control cabinet mainly by the electric drive components, outside the operating device, intelligent controller, the specific layout shown in Figure 1.
The electrical driving part in the control cabinet is similar to the driving devices used in the control cabinet on the market at present, and is composed of disconnecting switch, circuit breaker, lightning arrester, TSE, step-down and full-voltage starting device, but with the traditional control cabinet All devices are arranged in a shell. The difference is that the cabinet inside the control cabinet is divided into common and spare two compartments by a fireproof board. The common driving components are arranged in independent compartments on the right. The spare driving components, TSE and The intelligent controller is placed in the spare compartment on the left. The advantage of this arrangement is that when the common driving device generates arc or spark due to abnormal conditions such as short circuit and so on, even if the common driving device is burned, the spare device will not be affected due to the function of the fireproof board, The role of traditional control cabinet to take the device layout can not achieve this effect.

In the control panel panel installed isolation switch and circuit breaker outside the operating handle, engineers and technicians fire pump control cabinet for maintenance and overhaul, you can use these hand-operated device to power down before opening the door operation. Avoid the traditional control cabinet often occurs when the operator opened the door to bring the dangers of electricity and maintenance must be removed when the main switch of the drawbacks and greatly enhance the safety and regulatory control cabinet operation.

Intelligent controller installation is the core part of the system control, installed in the control panel panel, the composition of the block diagram shown in Figure II. The intelligent controller takes the PIC microcontroller as the main control unit and the surrounding area is equipped with a sampling processing module, a clock module, a 485 communication module and a human-machine operation unit of the LCD liquid crystal display, which are mainly composed of a special power processing chip ATT7026A. Integrated intelligent dual power switch function, fire pump automatic periodic inspection function, remote communication function, motor protection and system parameters real-time query and modify functions.

Function and features

3.1 fire pump start

The electric fire pump control cabinet based on the majority of domestic buildings with a configuration with a fire pump to the actual design to provide local start, emergency start, start the fire and remote start four start-up mode, in addition to emergency start, the other three Kinds of start-up methods are connected to the intelligent controller. When the start signal is received, the intelligent controller will automatically start the common pump. When the common pump encounters a fault such as a short circuit or overload, the system will stop the common pump first, then start the standby pump by delay 10s, Fault alarm and record. Emergency start is not controlled by the intelligent controller startup mode, usually only when the intelligent controller does not work properly when it comes into operation; the operator can start the pump through the emergency start button on the control panel.

Control cabinet also supports full-fire pump and stellate delta buck start mode, in the design, the control cabinet reserved for step-down and full-pressure starter installation location, the intelligent controller also reserves a control interface. Using different start-up methods, just install the corresponding starter, do not need to change the structure and wiring control cabinet.

3.2 dual power switch function

At present, the dual power supply cabinets and fire pump control cabinets in the fire protection market are generally provided by two independent manufacturers. The traditional fire pump control cabinet with dual power switching functions is generally controlled by a single dual power supply cabinet with a fire pump control Cabinet to achieve. Such a dual-power fire pump control cabinet is not only costly, but also has a complicated structure and a large floor area due to the addition of a control cabinet, which presents great difficulties in maintenance and system upgrade.

As a leading ATSE production and design company in China, our company has advanced technology and rich field experience in smart ATSE. In the new fire pump control cabinet we embedded intelligent dual power switching technology, based on the same ATSE ontology, the ATSE controller software integrated into the intelligent controller to achieve two power switching function, the system In the space of only one cabinet, the intelligent dual power switch function and the electric fire pump control function are realized.

3.3 cycle automatic inspection

Leakage currents flow through stationary fire pumps over a long period of time when the fire pump is not working, carrying sand, building concrete, lime, rust, etc. and accumulating in the fire pump, causing the pump body, bottom valve and check valve to jam Or rust, so that the device can not play a role in the event of a fire, causing undue loss. GBT21208, "civil regulations" and "high regulation" for the pump of this problem, are clearly required fire pump to be regularly commissioning. Traditional fire pump maintenance is usually carried out by manually testing the pump for a period of time to prevent the pump from catching or rusting.

The new fire pump control cabinet using powerful clock chip RX8025, through the software to achieve the pump's automatic periodic inspection function, greatly reducing the workload of the fire pump maintenance. Through the LCD operator interface on the control cabinet door, the operator can conveniently set the period (month and week) and the specific time (hour and minute) of the fire pump inspection. The system uses the interrupt trigger method to start the pump inspection function, the default interval of one month (adjustable cycle). After the inspection time, if there is no fire, the system first opens the relief valve for 10 minutes, and then starts the common pump for 10 seconds after the water in the building pipe network flows out. After the common pump test run time stops the common pump, and then Delay 5 minutes to start the standby pump 10s, spare pump test run time to stop the standby pump and close the pressure relief valve on the panel LCD screen output Chinese inspection report, at the same time through the 485 bus test information sent to the central Control room. In the inspection process, if suddenly received a fire start signal, immediately exit the fire pump inspection, into the normal fire pump program.

3.4 Motor Protection

The intelligent controller integrates two power supply voltage and current sampling circuits and function modules, wherein the current acquisition adopts the two-level sampling as shown in FIG. 1 and FIG. 2, so that the control cabinet of different models and power needs only to connect the control cabinet The replacement of the high-current transformers in the backup housing into the appropriate model without changing the sampling circuit in the intelligent controller.

The system samples the current and voltage in the circuit every 330ms, and judges the working status of fire pump and ATSE according to the sampled data. When the fire pump overload or stall due to anomalies, the system will immediately send an alarm, and according to the design requirements to make the appropriate action. As a result of a fire, shutting down the fire pump to protect the equipment may result in the fire pump being destroyed by the fire, together with the building and its internal property. The standard GBT21208 stipulates that while starting a faulty fire pump may cause temporary damage to the conductors, equipment and motors Sexual or permanent damage, but should still be started, and the fire pump in the event of stalling should be able to continue to run 8 to 20 seconds, 3Ie over-current, the fire pump to be able to keep running at least 3 minutes. In order to meet this requirement, the new type of control cabinet uses a special circuit breaker of our company, and removes the bimetal in the circuit breaker so that it does not have the thermal trip performance. At the same time in order to ensure that the circuit breaker has enough overload capacity, and we have carried out the re-release of the solenoid design. In addition, through the software design, the function of delay and automatic shutdown of the fire pump under blocking and overcurrent conditions is realized, and the protection of the fire pump motor is realized under the requirements of meeting the requirements of the national standard and extinguishing fire.

3.5 remote monitoring

The system integrates 485 communication module, remote alarm and remote start module, which can be conveniently connected to the central control computer in the building. When the fire pump system fails, the intelligent controller will immediately send the corresponding alarm information to the central control room computer. The central control room can also query or modify the system parameters of the fire pump control cabinet and the running status of each device in real time through a computer. With the development of network technology, if the fire pump system in the building is to be networked, only a network adapter in the control cabinet or a network to serial port module in the intelligent controller can be easily implemented upgrade.

3.6 Human Machine Interface

The new fire pump control panel panel installed 192 * 64 dot matrix LCD screen, the use of full Chinese display, the user can easily through the intelligent controller on the system parameters (such as current, voltage, inspection time, historical failure Etc.) to query and modify. In addition, the system also provides LCD screen, LED indicator, buzzer and sound and light alarm four alarm mode, when a fault occurs, the system immediately according to the severity of the fault using the national standard requirements for alarm. If the fire pump can not start, the LCD screen pops up the prompt interface of Chinese promptly, and the audible and visual alarm will be immediately called (this fault is serious, without LED lamp and buzzer alarm), meanwhile, the system can not pass fire pump through 485 bus Start the fault passed to the central control room computer to remind the monitoring staff to deal with.

The new type of control cabinet in strict accordance with the national standard requirements, the use of programmable controller for control system design, not only greatly increased the electric fire pump control automation and intelligence, but also makes the entire system structure is more simple and further improve the fire System reliability and normativity. The system fully considered the development trend of fire pump control system and high-rise building fire pump control cabinet higher and higher requirements in the hardware and software design reserved control interface and software modules can be easily based on the actual situation For function expansion and system upgrade.

In addition, the system's intelligent controller has a strong compatibility, for different power of fire pumps and different start-up mode, without replacing the intelligent controller, only through the LCD screen for key operation or remote set by the computer, change the appropriate The system parameters can be.

At present, the new type of fire pump control cabinet developed by our company has completed the prototype production. All the functions meet the design requirements. The EMC test of the hardware has reached the requirement of GBT21208-2007 and the electrical performance has also passed the test of special testing organization Testing, it has now entered the marketing phase.