real image of my complete machine

on the post before, I've shown my incomplete "Automatic smoke absorber machine", but on this post, I will show off my real image of my complete machine. Below are the image:-

Automatic smoke absorber machine on the front view with the water tank

on the back view of machine

control system board stay under the machine, surface on the water tank

on the side view ( last stage) where exhaust fan located and behind the exhaust fan had sensor where functioning to sense the quality of air for the last stage.

all the part of my machine are completed, so it can be test before present it on Industrial Day on 8th November 2012.

alter the PLC program...

in the post before, I've put my PLC program, but while running the programme, it's not fulfil the specification for my main objective. So that, the programme have been alter by adding edge triggered wiping relay and remove the on delay from the programme.

Edge triggered wiping relay Short description

 An input pulse generates a pre-set number of output pulses with a defined pulse/pause ratio (re-trigger able), after a configured delay time has expired.

above is the programme that have been altered by adding edge triggered wiping relay where the pulse for the red line is about 20m which equal to 20 seconds.

above is the last result output while the programme run. after the 3 system function simultaneously ( water pump 1, water pump 2, exhaust fan) about 20 seconds, the last output will get out  with the green color where shows the smoke at the last stage are not dirt, if the smoke on the last stage still dirt, last sensor will shows the red color of LED. the red LED are not programme through PLC Logo because the sensor was in separate system. It just to show the smoke still dirt or not.

added new simple circuit to project

smoke sensor MQ2 used DC supply to operate,the output from sensor cannot be entered to PLC Siemens Logo because that things used  AC supply to operate, so that I need to convert output from MQ2 to AC form. I need to combine the comparator circuit with relay to the output of MQ2, then the input for Siemens Logo can be operate normally in AC form.

above is the circuit for the comparator design. the output from the comparator circuit will be connected to relay and the output from the relay will connect to the input for the PLC Logo. To construct this circuit, it needs amplifier OP07 with the variable resistor and 1k ohm resistor.

Voltage comparator is a circuit which compares two voltages and switches the output to either high or low state depending upon which voltage is higher. A voltage comparator based on opamp is shown here. Fig1 shows a voltage comparator in inverting mode

In non inverting comparator the reference voltage is applied to the inverting input and the voltage to be compared is applied to the non inverting input. Whenever the voltage to be compared (Vin) goes above the reference voltage , the output of the opamp swings to positive saturation (V+) and vice versa. Actually what happens is that, the difference between Vin and Vref, (Vin – Vref) will be a positive value and is amplified to infinity by the opamp. Since there is no feedback resistor Rf, the opamp is in open loop mode and so the voltage gain (Av) will be close to infinity. So the output voltage swings to the maximum possible value ie; V+. Remember the equation Av = 1 + (Rf/R1). When the Vin goes below Vref, the reverse occurs.

So that, the output from the comparator circuit can be supported by the AC voltage because the voltage gain  close to infinity.

the program using Siemens LOGO ( programmable relays)

image above is the example of the LOGO programming.

LOGO programming is the easy programming to be program because it just use logic gate to program.

LOGO programming is the alternative to replace the relay circuit that more complicated and need to build much circuit to function it. this system can be insert 4 input and maximum output are 8 output.

image above show the first simulation for the first counter. the counter count for 20 minutes before the circuit follow up for the next function. red wire in the circuit shows the simulation running but in blue wire means that the system hold until the counter finish to count.

added new part to the machine

image above is the top view of the machine after the water mist system and water pump connect together

on the side view of the machine after connecting water pump and water mist system.

on the next time, the complete image of the system together with the system will be uploaded to show the real of smoke absorber machine. now, I am doing the the control system using Siemen's LOGO programmable relays.