Fully Protected Star Delta Circuit With Liquid Level Relay
It will protect the motor by putting devices such as thermal relay, phase protection, ptc in the fully protected star-delta circuit with liquid level relay.
The thermal relay will protect the motor from current. The phase protection relay will protect the motor by controlling the absence of phase and phase sequence.
Ptc relay will protect the motor from heat and prevent damage to the windings.
Therefore, by using such protection devices, the engine will be protected against sudden problems.
Fully Protected star delta circuit control circuit connection with liquid level relay
We get out of the control fuse and connect it to the terminal 95 of the thermal relay closed contact (NC).
By removing the cable from the thermal relay closed contact (NC) terminal 96. We connect the voltage protection relay to the common (COM) terminal.
Voltage protection relay is a relay that monitors 3-phase undervoltage, overvoltage, phase sequence and absence.
Instead of using multiple relays, we can control all processes with a single relay.
Open contact or closed contact changes according to the voltage protection relay you will use.
We leave the voltage protection relay closed contact (NC) terminal and connect it to the PTC Thermistor relay com terminal.
By removing the wire from the Ptc Thermistor relay open contact (NO) end.
We connect the emergency stop closed contact (NC) to the input terminal.
We leave the emergency stop closed contact (NC) output and connect it to the stop button closed contact (NC) input terminal.
Leave the stop button closed contact (NC) output end and connect it to the com terminal of the liquid level relay.
We leave the liquid level relay open contact (NO) end and connect it to the A1 terminal of the M contactor.
Therefore, we make the neutral connection to the A2 terminal of the M contactor.
Star Delta Controller Connection
Then, we take a cable from the level relay open contact (NO) output end and connect it to the closed contact (NC) input end of the delta contactor.
We connect the triangle contactor to the time relay A1 terminal by leaving the closed contact (NC) output. We make the neutral connection to the time relay A2 terminal.
Then we take a cable from the closed contact (NC) input end of the delta contactor that we have just connected.
We connect the cable we bought to the com end of the time relay. We leave the time relay closed contact (NC) end and connect it to another closed contact (NC) input end of the delta contactor.
leave the closed contact (NC) output end of the delta contactor and connect it to the A1 terminal of the star contactor.
Therefore, we make the neutral connection of the star contactor to the A2 terminal.
We do not operate according to the project, as we have connected to the com end of the time relay before.
Leave the time relay open contact (NO) end and connect it to the closed contact (NC) input end of the star contactor.
We connect the star contactor to the A1 terminal of the delta contactor by leaving the closed contact (NC) output end. Then, we make the neutral connection to the A2 terminal of the delta contactor.
We take a cable from the com end of the time relay and connect it to the open contact (NO) end of the delta contactor.
By leaving the open contact (NO) output of the delta contactor. We connect the star contactor to the previously used closed contact (NC) terminal input. Thus, the connection of the control circuit is finished.
Connection of liquid level phase protection thermistor relays
In order for the phase protection relay to work in the circuit. We connect 380 volt power cables to the L1 L2 L3 terminals.
And we make the neutral connection to the N terminal of the phase protection relay. In the thermal relay, we need to adjust the current.
Then we connect the ptc cables coming from the motor to the PTC terminal of the PTC thermistor relay.
This PTC cable has two wires and connects in any way.
In order for the PTC thermistor relay to work, we make the neutral connection to the part where L is written, to the place where the phase N is written.
In order for the liquid level relay to work, we make a neutral connection to the place where L is written and phase N is written.
If we want only enable/disable operation, two probes must be connected. If you want it to work at the upper level and at the lower level, you must use three probes.
Or if you want it to work at a higher level, you need to make three probe connections again. These two or three probe cables are connected to the places written with letters.
Thus, there is no missing process for the operation of the control circuit.
Operation of the control circuit
If the emergency stop is pressed when we energize the control circuit. The circuit will not work because there will be no electrical voltage transition.
We remove the emergency stop button. The thermal relay will be installed and electrical voltage will pass through its closed contact.
When the phase voltage protection relay detects that it is 3 phase balanced and 3 phase. İt will close its contact and transmit the electrical voltage.
The thermistor relay will detect that the motor is not hot and will transmit electrical voltage by closing its contact.
The last process for the operation of the circuit will come to the liquid level relay.
If we use the liquid level relay to empty a tank. İt will close its contact when water reaches the upper level.
When the liquid level relay closes its contact. İt will command the star delta circuit to operate.
It will draw the M contactor at the first moment, while the star contactor will also be drawn. And the engine will run stellar at first.
At the same time, since the time relay will be energized, it will start counting the set time.
At the end of the set time. The timer will open its closed contact and stop the star contactor. It will close the open contact and activate the delta contactor.
Therefore, the motor will now start working in delta.
It immediately passes from star to triangle. Then, when the water in the well decreases. The level relay will stop the system by opening the contact that it closed. And the lower probe is not short-circuited.
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Good luck with your work. You have set up a very nice circuit. Thanks to you, I made the circuit myself. Thank you very much.
thank you.
Thank you