Automation
Automation of hydrophore unit
Hydrophore unit uses to provide freshwater or seawater under pressure to consumers. When pressure inside hydrophore tank reducing below working pressure, the pressure switch initiate pump start-up and supply water to the tank automatically. When pressure inside the tank exceeding upper limit of the working pressure, the pressure switch stopped the pump automatically.
Pressure switch setting (see figure below)
The range is set by using the setting knob 4 while at the same time reading the scale 3. For setting an adjustable differential the front cover 2 must be removed. The differential disc 1 must be set in accordance with suitable differential pressure. To ensure that the hydrophore unit functions properly, a suitable differential pressure is necessary. Too small a differential will give rise to short running periods with a risk of hunting. Too high a differential will result in large pressure oscillations.
Pressure switch DANFOSS type RT
1 – differential setting disc, 2 – front cover, 3 – range scale, 4 – setting knob, 5 – pressure switch body, 6 – cable holes, 7 – contact system, 8 – pressure connection
The production of hot water at constant temperature ensures automatically by temperature switch (calorifier heated by electricity) and temperature regulating system (calorifier heated by steam).
In case of calorifier heated by electricity, steam valves are closed and temperature regulating valve not using. Meanwhile utilizes electrical heaters with automatically temperature control by temperature switch.
Electrical heating capacity was generally divided as follows: small and large.
In the case of controlling of large electrical heating capacity operation will be done step by step from small capacity, for instance 15 kW plus 15 kW is large capacity 30 kW. According to the divided electrical heaters, temperature switch uses for setting of the temperature, regulator and then, em'cy temperature uses for setting of em'cy purpose. By setting point of temperature switch, heater will be operated automatically.
Commonly electrical heater is to be provided with an interlocked over
temperature
thermostat with manual reset.
Temperature switch (figure below)
Temperature switch DANFOSS type RT with temperature sensor
1 – capillary tube, 2 – differential setting disc, 3 – front cover, 4 – range scale, 5 – setting knob, 6 – temperature switch body, 7 – cable holes, 8 – contact system, 9 – cylindrical remote temperature sensor
The temperature setting point is set by using the setting
knob 5 while at the same time reading the scale 4. For setting an adjustable
differential the front cover 3 must be removed. The differential disc 2 must be
set in accordance with suitable differential pressure. To ensure that the
calorifier functions properly, a suitable setting point of temperature switch is necessary.
Temperature regulating system (see figure below)
Self-acting temperature regulating valve (briefly called as TRV) is applied for temperature auto-control in hot water circulates line.
The serials TRV are designed according to the principle of liquid expansion. The volume of sensor liquid reduces or increases with temperature, driving the regulating valve, adjusting the flowrate of the steam, with the changing of the flowrate, as required and automatically maintain hot water at constant temperature.
1 – steam valve, 2 – cooler, 3 – thermostat, 4 – temperature scale, 5 – slotted screw, 6 – indicating sleeve, 7 – adjusting handle, 8 – temperature senor, 9 – capillary tube
In order to reset the sensor temperature which should be of
the same scale to the thermometer installed in equipment, work loose the
slotted screw (5) and then arrange the temperature scale (4) at the end of the indicating sleeve (6). Tighten the
slotted screw.
A. For higher temperature setting: rotate slowly the adjusting handle (7)
clockwise (CW) for the precision temperature setting. The temperature changes
at range of ±10 per ℃ two revolutions of adjusting handle.
B. For lower temperature setting : it is the same of the case for higher temperature setting, except to rotate counter-clockwise (CCW).
Automatic control of the salinity in the FW
The FWG is furnished a salinity alarm which automatically continuously measures the salinity of the produced distillate. The salinity alarm gives an alarm if the salt content exceeds prescribed value. In addition to the alarm LED lamp, a solenoid valve is operated which automatically return improper produced water with high salinity to the evaporator.
When the salinity drops to the normal level, the alarm circuit automatically resets and consequently alarm LED lamp turns off, the solenoid valve closes, and the distillate with high purity again begins to flow into the FW tank.
UV sterilization unit automation
UV sterilizer JOWA UV1
The sterilising process is controlled by a microprocessor which collects data from the UV-sensor and the lamp monitoring system. It gives all necessary information to the user in a display window. If a lamp failure arises, it tells you which lamp to change. It also tells you when to change all lamps because of age. If the sterilizing dosage is below acceptance the unit shuts off the flow and call for attention.
Schematic diagram of UV sterilizer JOWA UV1
UV Sterilizer HANSUN UIV-1.3
The control system is arranged through a controller program, which collect information from UV sensor and lamp monitors, so that the solenoid valve on water outlet can be controlled at such conditions like the Lamp failure and the UV dosage lower, the solenoid valve will be closed, to protect unqualified water passing through to potable water system; meanwhile, a lamp running-hours accumulator will deliver alarm while running hours reaches to 7200 hours and valve will be closed when running hours reaches 8000 hours.
Schematic diagram of UV Sterilizer HANSUN UIV-1.3