Automation of process equipment of central heating station - Administrative building
- Added: 01.07.2014
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1. Purpose and composition of automation system
The automation system is designed to automate the operation of individual heat station equipment as part of the following process systems:
hot water supply systems;
heating and ventilation makeup systems.
The main elements of the automation system are:
- SHA automation cabinet with Excel Web microprocessor controller (XL1000C100).
- peripheral devices of a system of automatic equipment (sensors of temperature and pressure, pressure difference sensors relays, differential sensors of pressure, actuators);
- elements of switching and start-up equipment of control cabinets (signal contacts of frequency converters, intermediate relays, magnetic starters, control switches).
2. Control modes.
Two control modes are provided by the ITP processing equipment: automatic (A) and manual (P).
Automatic control mode is the main mode and is intended for control of process equipment by algorithms of microprocessor controller programs.
Change of control modes is carried out by service staff by transfer of the P0A switches located on the front panel of the control cabinet to the relevant provision.
In automatic control mode, the automation system performs the following:
- maintaining the coolant temperature in the heating system (according to the set temperature schedule of the heat supply organization) by changing the flow rate of the network coolant through the CO heat exchanger;
- maintaining the water temperature in the ventilation system by changing the flow rate of the network coolant through the CB heat exchanger;
- maintaining the water temperature in the hot water supply system by changing the flow rate of the network coolant through the WAN heat exchanger;
- maintaining coolant pressure in the reverse circuit of heating and ventilation systems by controlling solenoid valves;
- control of pump groups.
Manual control mode is used to start pumps during commissioning and maintenance
3. Guidelines for ASW development.
Application software should be developed by a specialized organization. During development of control algorithms and ASW of controllers provide:
- PID control in all control circuits;
- possibility of temperature schedule correction;
- program protection against temperature excess (in relation to the specified temperature schedule) in the return network pipeline.