3.696.5275.210
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Water Temperature in Pre-Heating/Degassing Tank
(Fig. 14)
Water temperature is revealed in pre-heating tank by a three wire heat-resistant temperature
probe, fitted with a measure transmitter which is installed in mid-tank on the primary steam
supply side. The temperature probe sends the 0-10 V signal (equivalent to 0÷100°C range)
to PLC control unit, which elaborate it and consequently transmits the modulanting control
signal to the piston control valve on the primary supply line to inlet steam into the steam
generator tank.
Water Level in Pre-Heating/Degassing Tank
(Fig. 14)
The pre-heating tank water level is relieved by the level transmitter installed at the bottom
of the tank.
The level transmitter sends the 0-10 V signal (equivalent to 0÷ 100 mbar range) to PLC
control unit, which elaborates it and consequently transmits the ON-OFF control signal
to the piston control valve on the feed water line, to inlet feedwater into pre-heating tank.
Clean Steam Pressure
(Figg. 15 and 16)
Clean steam pressure is relieved by the relevant pressure transmitter which is installed on
the tank head of the boiler. The pressure transmitter sends the 0-10 V signal (equivalent
to 0÷6 bar g range) to PLC control unit, which processes it with a PID algorithm and
consequently transmits the adjusting control signal to the pneumatic control valve to
modulating inlet of steam into heat exchanger coils integrated into the steam generator.
Fig. 14
Level
(differential pressure)
transmitter
(pre-heating tank)
Probe and temperature
transmitter
(pre-heating tank)
Pressure
transmitter
(clean steam)
Pneumatic
control valve
(primary steam)
Fig. 15
Fig. 16
Summary of Contents for CSM-C
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