Hi i have recently been studying PLC for work and i have had a task now which i believe i am close to finishing but i cannot think how to correct my problem. Any help would be much appreciated.
I need to run the mixing tank for 10 seconds and then empty the tank after but i can only manage to get them both to come on at the same time but i need the empty tank to come on after the 10 seconds. I cant see where i am going wrong as i have tried several ways and i just end up braking the rest of the circuit.
this is what i have been given if anyone could see a solution to my problem or let me know if i am way off.
• When the Start ‘push to make’ (not toggle) switch (I1) is pressed/released and gets latched on (B1: RS latch), the start ‘fill’ pump (Q1) will be energized and the tank will start to fill.
• The pulses generated by flow meter 1 (B5: pulse generator) should be used to increment the counter (B6: Up/down). Tank level full is when the counter function on = 10 and tank low level is when counter off = 1. These values can be used as feedback to control the pumps (instead of the high/low level sensors shown above) and can be called the ‘tank high/low level count indicator’ (Q5 or use a flag M1)
• When the full liquid level in the tank is sensed by the tank high/low level count indicator (Q5), the fill pump will be shut-off and the FULL light (Q2) on the control panel is to be energized.
• When the tank is full, start the mixer (Q3) and run for 10 seconds (B8: off-delay timer).
• When the 10 seconds has expired, stop the mixer (Q3) and start ‘empty’ pump P3 (Q4).
• Pump 3 (Q4) will be required to run until the tank is empty. Tank empty can be detected using the low-level sensor (I3).
• The pulses generated by flow meter 3 (B15) should be used to decrement the counter (B6: Up/down). Tank empty can be detected by the high/low level count indicator (Q5 or use a flag M1) to switch off the pump
• When the stop button (I2) is operated, the process must stop immediately (Q1, Q3, Q4).
Thanks
I need to run the mixing tank for 10 seconds and then empty the tank after but i can only manage to get them both to come on at the same time but i need the empty tank to come on after the 10 seconds. I cant see where i am going wrong as i have tried several ways and i just end up braking the rest of the circuit.
this is what i have been given if anyone could see a solution to my problem or let me know if i am way off.
• When the Start ‘push to make’ (not toggle) switch (I1) is pressed/released and gets latched on (B1: RS latch), the start ‘fill’ pump (Q1) will be energized and the tank will start to fill.
• The pulses generated by flow meter 1 (B5: pulse generator) should be used to increment the counter (B6: Up/down). Tank level full is when the counter function on = 10 and tank low level is when counter off = 1. These values can be used as feedback to control the pumps (instead of the high/low level sensors shown above) and can be called the ‘tank high/low level count indicator’ (Q5 or use a flag M1)
• When the full liquid level in the tank is sensed by the tank high/low level count indicator (Q5), the fill pump will be shut-off and the FULL light (Q2) on the control panel is to be energized.
• When the tank is full, start the mixer (Q3) and run for 10 seconds (B8: off-delay timer).
• When the 10 seconds has expired, stop the mixer (Q3) and start ‘empty’ pump P3 (Q4).
• Pump 3 (Q4) will be required to run until the tank is empty. Tank empty can be detected using the low-level sensor (I3).
• The pulses generated by flow meter 3 (B15) should be used to decrement the counter (B6: Up/down). Tank empty can be detected by the high/low level count indicator (Q5 or use a flag M1) to switch off the pump
• When the stop button (I2) is operated, the process must stop immediately (Q1, Q3, Q4).
Thanks
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