Figure 1 C650 lathe electrical control main circuit
Figure 1 is the main circuit of the C650 lathe, equipped with three motors M1, M2, M3. The main motor M1 consists of stop button SB, jog button SB1, forward rotation button SB2, reverse button SB3, thermal relay normally open contact FR1, speed relay forward contact KS1, speed relay reverse contact KS2, forward contact The main contact KM1, the reverse contactor main contact KM2, and the brake contactor main contact KM3 are controlled.
Cooling pump motor M2 is controlled by stop button SB4, start button SB5, thermal relay normally open contact FR1, contactor main contact KM4, etc.; fast shift motor M3 is controlled by limit switch SQ and contactor main contact KM5; current meter A It is controlled by the intermediate relay contact KA. The I/O configuration of the PLC controlled by the electrical control components is shown in the following table. The I/O wiring of the PLC control of the C650 lathe is shown in Figure 2.
Table C650 lathe PLC control element configuration table
Electrical control symbolFeatures
PLC
Programming element
Electrical control symbol
Features
PLC
Programming element
SB
M1 stop button
X0
KS1
Speed ​​relay forward contact
X11
SB1
M1 jog button
X1
KS2
Speed ​​relay reverse contact
X12
SB2
M1 forward button
X2
KM1
M1 positive contactor main contact
Y0
SB3
M1 reverse button
X3
KM2
M1 reversal contactor main contact
Y1
SB4
M2 stop button
X4
KM3
M1 brake contactor main contact
Y2
SB5
M2 start button
X5
KM4
M2 contactor main contact
Y3
SQ
M3 limit switch
X6
KM5
M3 contactor main contact
Y4
FR1
M1 thermal relay normally open contacts
X7
KA
Ammeter relay contact
Y5
FR2
M2 thermal relay normally open contacts
X10
Figure 2 C650 lathe PLC control I/O wiring diagram
Figure 3 is a ladder diagram for the PLC control of the C650 lathe. The MC master command and the MCR master reset command are used for programming. After the lathe is powered, because the stop button SB and the thermal relay FR are not activated, X0 and X7 of the fourth branch are closed and M110 is energized, causing the fifth branch M110 to close, and the program executes the MC master command to the MCR master reset command. The master program between.
Fig. 3 Ladder of PLC control of C650 lathe
Second, the main motor positive control 1. Forward rotation control Press the main motor forward rotation button SB2, and the 6th branch X2 is closed. Since X3 and M102 do not operate, M101 is energized and locked by the M101 of the 7th branch. Cause the following 3 results:
1 The eighth branch M101 is closed, and T1 starts 0.5S.
2 The 12th branch of the M101 auxiliary normally closed contact is disconnected, so that the reversing start auxiliary relay M102 is powered off and the interlocking between forward rotation and reverse rotation is realized.
3 The M101 of the 17th branch is closed, Y2 is energized, and the KM3 is pulled in the main circuit to short the string resistance R.
When the eighth branch T1 delays 0.5s, it will cause the T1 branch of the ninth branch to close. Since the Y1 branch of the ninth branch is in the closed state, Y0 is energized; Y0 of the 15th branch of the 15th branch is disconnected, and the main circuit master Contact KM1 is closed. Motor M1 starts forward operation.
2. T1 delay action T1 delay 0.5S to ensure that the main circuit KM3 first pull, make the string resistor R short, and then connect the M1 forward control main contact KM1; otherwise, the contactor KM1, KM3 then The command to pass is issued from the PLC control software at almost the same time, which may cause the KM1 to be turned on first and the KM3 to be turned on. The string resistance R cannot be shorted first.
After the motor M1 is started, the rotation speed rises. When the rotation speed increases to 100r/min, the positive relay contact KS1 of the speed relay is closed, and the X11 of the 22nd branch is closed, which is a good preparation for forward rotation and reverse connection.
3. Reverse control and T2 delay Press SB3, motor M1 will start reverse running, through the role of T2 delay 0.5S to ensure that the main circuit KM3 first pull, make the string resistor R short, and then connect M1 Reverse the main contact KM2.
Third, the main motor jogging control When the forward jog button SB1 is pressed, X1 of the second leg and the fifth leg are both closed, M103 of the first leg is energized by X1 of the second leg, and is locked by the M103 of the third leg. At the same time, the M103 of the 22nd branch is also closed, ready for T3 power.
Once the lathe is powered on, the M110 of the 5th branch is immediately closed. At this time, because X1 in this branch is closed, the M100 is powered on, the 10th branch M100 is closed, the 9th branch Y0 is energized, and the 22nd branch is often The auxiliary auxiliary contact Y0 is closed.
In the main circuit of lathe electrical control, due to the energization of the ninth branch Y0, the main contactor KM1 of the contactor pulls in and the main motor M1 starts rotating in the forward direction. After the speed exceeds 100 r/min, the forward relay KS1 of the speed relay remains closed. At the same time, the X11 of the 22nd branch is closed, so that it is ready for the opposing system.
1. M1 power-off deceleration Loosen forward jog button SB1, X1 of the 2nd branch and 5th branch are all disconnected, M100 of the 5th branch is powered off, and M100 of the 10th branch is disconnected. The ninth branch Y0 is powered off, and the Y0 contact of the 22nd branch is closed. The main contact KM1 in the main circuit is disconnected, and the main motor M1 is de-energized and decelerated.
2. M1 reverse braking Due to the early deceleration, the speed relay contact KS1 is in the closed state, so the X11 in the 22nd branch is closed, and the Y0 contact in this branch is closed, so the T3 is energized and the delay begins.
After the T3 delay arrives, the T3 contact of the 16th branch is closed, leading to the energization of the 15th branch Y1. The main contact KM2 in the main circuit pulls in, and the main motor M1 is braked in reverse.
3. When the speed of reverse brake is reduced to less than 100r/min, the positive relay contact KS1 of the speed relay is disconnected, X11 of the 22nd branch is disconnected, and T3 is powered off, and the T3 contact of the 16th branch is turned off. Disconnected, Y1 of the 15th branch will be cut off.
In the main circuit, the KM3 main contact is disconnected, the reverse brake is ended, and the main motor M1 stops.
4. Delay function of T3 The role of T3 delay 0.5S is to ensure that the KM1 is disconnected first and then the KM2 is switched on; otherwise, the KM2 is connected before the KM1 is disconnected, which will cause the main motor M1 winding to burn.
Fifth, the main motor reverse brake 1. The main motor is de-energized and the stop button SB is pressed. The fourth branch X0 is disconnected and the M110 is de-energized. The normally open contact M110 of the fifth branch is disconnected, and the master control circuit between the MC and the MCR is no longer executed. Y0 of the 9th branch was cut off due to power failure.
The main circuit KM1 disconnected, the main motor M1 power down, but as long as the speed of the main motor M1 is greater than 100r/min, the speed relay's forward contact KS1 is still closed, and the first branch of M103 due to self-locking and power.
When the stop button SB is pressed, the normally closed auxiliary contact X0 of the ninth branch is disconnected, Y0 is de-energized, and the main contact KM1 controlled by Y0 in the electrical control main circuit is disconnected.
2. Enter the reverse braking state to release the stop button SB so that the SB is switched from the pressed state to the unpressed state. Then the fourth branch X0 is restored to be closed, the M110 is energized, and the M110 of the fifth branch is closed and is turned on. Perform the master control circuit between MC and MCR.
The normally-closed auxiliary contact X0 in the first branch also returns to the closed state, so the M103 is energized and the M103 of the 22nd branch remains closed. Since the speed of the main motor M1 is greater than 100 r/min, KS1 is in the closed state, and the X11 of the 22nd branch remains closed, causing the T3 to be energized, and the timing starts.
When the T3 time arrives, T3 of the 16th branch is closed, and Y1 of the 15th branch is energized. KM2 in the main circuit is closed, the motor M1 enters the reverse braking state, and the main motor M1 rapidly decelerates.
3. Effect of T3 delay T3 delay 0.5S is reflected in the main circuit of the electrical control, the first contact of KM1 is disconnected first, and the main contact of KM2 is closed again after 0.5S, which prevents instantaneous connection of KM1 and KM2. Helps to avoid motor winding burnout.
4. M1 stalls When the main motor M1 decelerates to below 100 r/min, the positive relay contact KS1 of the speed relay opens, causing X11 of the 22 branch circuit to be disconnected and T3 to lose power, causing the T3 of the 16th branch to disconnect. Y1 is de-energized, KM2 is disconnected in the main circuit, reverse braking is ended, and the main motor M1 is stopped.
5. Reverse stop Enter reverse brake If you press SB3 when starting, the main contacts KM3 and KM2 in the main circuit will be turned on at intervals of 0.5S, and the motor M1 will start reverse running. Then release the stop button SB, it will enter reverse rotation to stop the reverse braking process.
Six, the main circuit operating current monitoringDuring the start of the main motor reverse rotation, since one of the auxiliary relays M101 and M102 must be energized, T5 of the 19th branch is energized, and 10S begins. After the timing is reached, T5 of the 21st branch is closed, causing Y5 to be energized, the normally closed contact KT in the main circuit is disconnected, and the alternating current meter A monitors the operating current, thereby allowing A to avoid a large starting operating current.
VII. Cooling and Fast Motor Control The cooling pump motor M2 and the quick-moving motor M3 are all operated in one direction and the control is simple. When the cooling pump motor start button SB5 is pressed, X5 of the 25th branch is closed, Y3 is energized and self-locked, and the cooling pump motor M2 is started; and when the stop button SB4 is pressed, X4 of the 25th branch is disconnected and Y3 is disconnected. Electricity, cooling pump motor M2 power off.
According to the lower limit switch SQ, the X6 of the 27th branch is closed, Y4 is energized, and the quick-moving motor M3 is started; the limit switch SQ is released, and the quick-moving motor M3 is shut down and stopped.
Read the C650 lathe PLC control I/O wiring diagram and PLC ladder diagram.
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