scheme automation supply plant
Fig. 26. Scheme automation supply plant / - heated valves, 2 - oil filter: 3 - double-pass valve, 4 - heater, 5 - fan, 6 - electric motor, 7 - temperature controller, 8-regulating valve, 9 - control unit, 10 - knot regulation
Automatic Protection radiators from freezing is as follows:
(And if the system is off it gets cool air, the sensor mounted in front of the radiator, at a temperature below 4-3 В° C opens the valve on the coolant, thus achieving the heating radiators;
b) When the installer automatically opens the valve on the coolant, heaters warmed up, but then turn the fan motor;
c) for plant operation during the cold period in the event of coolant pressure drop, clogging radiators, etc. by installing a temperature sensor provided on the back of the tube or on the capacitor - the wire that turns off the system and opens the valve for heating radiators, the action of this sensor is eliminated at air heaters to + 3 В° C and above (due to the temperature sensor, installed in front of heaters).
With three shifts inlet protection system radiators from freezing the points "and" n "b" are usually not provided.
With automatic regulation of air handling systems in the event of exercise of the functions of heating should be provided to maintain a constant temperature in the premises, ie, the sensors must be installed in the characteristic points of the room. In regulating purely air inlet system provides the maintenance of constancy of supply air temperature, as shown in Fig. 26.
Automating the air curtain comes down to the automatic inclusion of the fan motor when you open the gate and disable it after the restoration of air temperature in the zone of the gate. Usually carried out as control parameters of the coolant.
Exhaust systems, performing general exchange hood, usually locked with the motor supply fan, and sometimes even with an electric exhaust fan with a valve in the exhaust shaft. This automation eliminates the work of only one of two systems - exhaust or fresh air.
For exhaust systems with local suction, especially in the allocation of toxic substances, provides for blocking the motor exhaust fan with production equipment. Blocking is carried out in such a way as to stop the fan motor stopped working would be served by their equipment. For example, electroplating and etching machines and semi-automatic with chrome and cyanide discharges must cease filing current, coolant flow, the movement of the conveyor, etc., at a stop serving their fans.