Microprocessor automation system for towers EVAPCO.
Developed and manufactured automation system for cooling towers EVAPCO.
Here, the table selection and automation schemes for cooling tower EVAPCO ATW at 2010.
Below is an example of the implemented project automation ATW cooler 284 for cooling the turbo, implemented in 2006. The equipment is currently running without comment. These controllers are now replaced by more modern.
Here you can download fragments of the automation project.
Here you can download table of cables to the draft cooling tower automation
Baseline data for the preparation of the project:
Terms of Reference.
Figure 1. The configuration of the cooling system for turbocompressors. Structural scheme.
Specifications of tower ATW 284-5J2
-Type cooling towers - two sections, with forced air cooling,
-Number of circulating pumps - 2, (22kW, 380V, star / triang.)
-Number of fans - 4, (11kW, 380V - 2 level fan motors.), Two fans per section
-Number of irrigation pumps - 2 (4kW, 380V.)
-Number of sections of the heater - 2 (9kW, 380.)
-Water level sensor in the pan - 2 -220V,
-Dimensions 11,04 m * 2,4 m * 4,1 m,
DESCRIPTION OF AUTOMATION SYSTEMS
The scheme of powering system
Automatic control system of cooling the turbo-compressor stations.
How the system works.
To ensure the independent operation of each cooling tower system is divided into 4 identical subsystems in each of which "master" information exchange controller supports KU. Controllers KSHIU-GR in each subsystem is installed on 2 pcs.
1. In a heated room on the first floor
2. In a heated room on the second floor.
The system has the ability to work in both automatic and manual mode.
The efficiency of the system remains in automatic mode even in the event of failure of controllers KSHIU-GR or damage information network.
When power is initialization and survey the status of all input circuits installed. If there is no accident, the system is ready for use. Moreover, if you select "Automatic", there is a transition system in standby mode.
If you receive a digital signal "Start cooling towers", with the CPU is consistent running circulation pumps, irrigation pumps continue to run (depending on system parameters) and more consistent execution of fans and the regulation of cooling power of system.
The regulation is carried out separately for the two sections by the on / off levels of fans. Всего возможны 5 градаций производительности установки по воздуху: Total possible 5 gradations by fan power:
1.Both fans are off
2. First step of first fan is on, second fan off,
3. First step of first fan is on, First step of second fan is on,
4. Second step of first fan is on, First step of second fan is on,
5. Second step of first fan is on, Second step of second fan is on,
Thus, regulation is carried out more smoothly, starting current in the network are reduced by reducing the number of simultaneously switching high-power loads.
Productivity of circulators does not change depending on the temperature drop at the inlet and outlet of the cooling tower.
Management of irrigation pumps is carried out manually. Regardless of the mode of the system (manual / automatic).
Connecting heaters can be either manually or automatically.
The current state of the system (which of the units are included and what the performance) is stored in nonvolatile memory controller and even when your power goes out and back on, the system goes into that mode of operation in which he had to power down. If you selected the first step on the fans in the manual mode, after a power outage and the back of the input, the system immediately goes into manual mode and will continue to work on the early stages of the fans. At the same fans turn on rather than simultaneously with 5-second spread in time to avoid inrush current. The same applies to the circulating pump.
Also, handing control of the circulation pumps to pressure on discharge pipe. When pressure drops below the minimum level is off. When the "pre-crash" pressure is sound and light alarm. When the maximum pressure is off the system.
Each subsystem is the minimum required level of control system, a fall below a specified alarms is "Crash" and stop circuit.
Upon full launch of the cooling circuit is given a discrete signal "system is working correctly" on the CPU.
If receive a digital signal "Stop" from the CPU circuit and stops the system , entering to standby mode.
The system includes the possibility of transmission of signals of the equipment is part of the circuit for transmission to the central processor for subsequent display the status of the cooling system on the operator panel.
In manual mode, the system can start / stop of equipment such as remote and on site.
The system is a rough estimate of electricity consumed by summing included in this time motors. There are mapping the current energy consumption in kW and the amount of accrual consumption in kilowatt hours. When configuring the system in the nonvolatile memory controller KU recorded estimates of real consumption by each unit by measuring at each operation of the plant.