IMPORTANT QUESTIONS AND ANSWERS EVERY AUTOMATION ENGINEER NEED?
QN.Can I add more than one format module in PLC?
Answer:
No, but for S7 you can add 8 numbers on the left and 8 numbers on the right. Question 11 from a friend: Can ES add a temperature module without changing the PLC? Answer: The format module connects directly via RS485. So ES can communicate with other MPU modules via RS485.
QN Is Delta PLC controlled by SCADA?
Answer:
Yes, you can read or write the contents of the program from MODBUS or Ethernet via PLC address. Question 13: A friend: How to connect to the 300 and 400 series PLCs using the SMP port Answer: The MPI port is used to communicate with the computer and put the program inside the PLC.
QN. What is the role of the capacitor in starting single-phase motors?
Answer:
In three-phase motors, because there is a phase difference between the three phases, there is a counter-phase in the motor, which causes a rotating field, which rotates the rotor, but in single-phase motors, such as phase and zero, we have this field on the way. There is no starter that can turn the rotor, so these motors use an auxiliary starter coil and series this coil with a capacitor called a starter capacitor to phase difference between the main winding field and Aid is created and causes the engine to start. This capacitor is no longer needed after starting and is removed from the circuit by the centrifugal switch.
QN About how to test three-phase capacitors that are used to modify the network power factor, as well as about the resistors that are connected to these capacitors and the size of these resistors, whether it depends on the capacitance of the capacitor Explain or not.
Answer:
The best way to test a capacitor is to use a clamp ammeter and the current size of the capacitors and its resistances have nothing to do with the capacitance and are related to the connection of the capacitors triangle.
QN. friend of Bimetal adjustment is selected according to the rated current of the motor with the starting current of the motor?
For example, should the type of startup be considered or not? What is the amp of thermal & magnetic switch to power the motor for direct start mode and for triangle star start mode ?? If the power of the 15 kW motor with a rated current of 29 amps, a power factor of 0.89 and an efficiency of 0.87)
Answer:
Generally, when buying, the rated current of the motor is in the middle of the bimetallic range, but according to the standard, the current is 1/1 to 1/1 times the rated current. The motor is tuned because the motors can withstand this percentage of overload, but this adjustment is not absolute and some adjust the bimetal current to the same rated current for more protection and more reliable motor.
QN Hello, I wanted to know what is the difference between applying ac voltage to a coil and dc voltage to the same electrical coil.
Answer:
In addition to having an ohmic resistance, each coil also has an inductive resistance, which ohmic resistance is almost constant in dlc, ac current, but the inductive resistance is directly related to the frequency. There is an ohm, but in ac it is a frequency of 50 and the inductor resistance has a value commensurate with the frequency.
