ICTS-New Sensors Replacement ReliabilityTest

We managed to get two samples from Keyence and Omron for testing of reliability. Both works on same principal but come with 20% pricing different.

PZ-V31 Keyence Self Contained Photosensor Switch Reflective 300m/LCD


Automatic Calibration Photoelectric Sensors
• Detections are unaffected by variations in target color or angle
• Excellent resistance to dust and dirt
• One touch, fully automatic calibration
• Unaffected by highly reflective target backgrounds
• 40 model variations available including quick disconnect types
• High-power red LED(Except for PZ-M71/V71)
Automatic calibration type. Virtually eliminates all detection and stability problems inherent with conventional photoelectric sensors.


Visible Red Beam (All models)
Allows for easy positioning of the beam spot on the target and quick alignment of the sensor heads.
M3 Stainless Steel Internal Thread
Improved Mounting Strength
• The PZ-V/M has an M3 thread.• This ensures the PZ-V/M is securely mounted bydoubling the mounting strength
High-power Custom E-max LED
Suitable for Dusty Environments
• A high-powered LED allows the PZ-V/M to function normally in very dustyenvironments.
IP-67 Rated Waterproof Housing
All Models IP-67 Rated
• IP-67 means the PZ-V/M can be used in even the harshest environments.• The sensor will also operate environments subject to water and other liquids.
HighIntensity Pass/Fail Indicator
Improved Visibility
• The sensor has a largevisual display and high-intensity LED. • Pass/Fail conditions can be easily seen allowing for remote monitoring of sensor operation.



E3S-CL Omron Background Suppression Sensor

Photoelectric Sensor With Adjustable Setting Distance in Rugged Metal Housing
Background suppression sensor with stable detection regardless of color, material, or size of a detecting object.
Adjustable setting distance: 2% or less differential travel at 20 cm.
Sensing unaffected by dirty lens.
Compact and with a long detection distance of 50 cm (E3S-CL2).
Solid body provides excellent durability.
Eliminates background influences with a hysteresis of only 2% max. (E3S-CL1).NPN/PNP output is switch selectable for easy application anywhere.
Light on/Dark on selectable.
Easy distance adjustments with a six-turn adjustment with indicator.
Mutual interference prevention function.


Test Method
1- Day and night time
2- Stationary and moving conveyor
3- Stationary and moving mooncakes
4- Actual production


Observation
1- The frequency of malfunction (missing signal or unnecessary signal triggered)
2- Sensor recalibration time for different product input

ICTS-Problem after actual run

Since the day one when we have the actual run of the mooncake season, suddenly out of nothing all 6 sensors are started to giving problem of unreliabilities. Sensor 5 and sensor 6 almost out of order. Sensor 7 cannot detect at all. Sensor 1,2,3, and 4 cannot give stable green light signal most of the time. As such now only box motion Fuji machine is being used now.

Call OMRON to inform, and when he come to check, he even do not understand why these E3Z-D62 cannot operate properly as the settings for this application are OK already. As such he would go back and do some testing with other type of sensors and would only give his result by Wednesday 27/6/07.

Meanwhile, Keyence will come by tomorrow to show their sensor capabilities that will suit our application. The decision to use which sensor type and brand would only be make by Mr YU TT once both parties already shown their test result together with the right price later on.

On PLC panel box wiring, all wiring are completed already. It just a matter of program transfering from PC to PLC. However, for safety reason I'm not going to use it yet until the hardwires circuit and sensors are all OK to avoid unnecessary problem.

While waiting for sensors replacement, I upgrade the PLC ladder diagram so that later on, only 5 units of sensor required rather than 7 now. I eliminate the sensor 4 and sensor 6. Next I put back the emergency switch for better handling of the machine. Here is the new ladder.

ICTS-Final Trial Run

Yesterday, we managed to do final trial run together with the contract workers to give them some feel of how this year production would looks like with the additional of the ICTS. Next, it also acts as our final analysis of what to do to improve the project so that some kaizen can be done. While this project is actually a manpower reduction project, it's intrinsict purpose is to slowly automate the process to reduce process tacttime as well as to reduce unnecessary proceses as well.
Since the packaging area has been accustomed to the traditional way of documenting and doing manual processing, the changing of the norm will have some resistance. In fact this is a normal and already expected as part of human nature.
In order to do fully automation, there are many more simple manual processes that have to be upgraded. However as for the time being, this ICTS will pioneer the kaizen activity that will stroll on in future. This ICTS will serve as example of how the rest of the process can be automated as well. While simplifying the processes automation also will lead to the decrease of the per unit cost of the mooncake.

Anyway, there are a few suggestions for ICTS improvement based on the trial run yesterday. They are :
1- The mooncake input to the conveyor system need improvement. Now everytime the operator put on 4 mooncakes he has to align them to the guide. While wasting time this job is actually unnecessary. The job can be eliminated if there is a better slider guide that allow the operator to simply insert the mooncake inside the slider tunnel where the alignment will be done by the slider itself. By doing this, only one operator is required to input rather than two for the time being. As for the design, the smoothness and the angle of the slider is very important where the gravity is the main force to pull the mooncake to the conveyor continuosly.
2- The sensors position between conveyor D and conveyor C, as well as conveyor C and conveyor B nned to be adjusted a bit to avoid collisions whenever the front conveyor stop.
3- The sensors S1 and S2 were a bit unreliable where sometimes the signal is not stable. When this thing happen, a collision in front of the pusher might happen causing mooncake damage. A solution could be changing to better sensor ssuch as keyence brand that cost more than RM500 aeach.
4. The switch box for START STOP and EMERGENCY needs to be install rather than switchews only for better access to the ICTS hardwires.

Meanwhile, since this year we are going to produce 4 colors (GREEN, PURPLE, PINK, BLACK) for snowy mooncakes, samples are needed ASAP to ensure that our existed sensors can work with them. Yet for small mooncakes, samples also needed ASAP as the alignment and ICTS adjustment are needed to ensure smooth operation of the machine.

ICTS-Panel Box Wiring

Yesterday after spending sometime reading the CPM1A I realize the I/O wiring mistake with the PLC. First I thought all the inputs switches must be tie to common. Instead I found out that whatever connected to input common must pass through a DC 24V supply before connecting to the inputs. The good thing the power supply orientation is optional. The common input can be connected to positive or negative of DC power supply as long as all the input are passed through the same supply.

As for the output, it also the same thing. I chose COM3 because it has 4 ports tied to it, output 4, output 5, output 6, and output 7. I connect output 4 to pneumatic valve, output 5 to conveyor D, output 6 to conveyor C, and output 7 to conveyor B. Since both input and output were connected already, then due to this wiring problem, I have to rework it today.

Due to unavailability of right switches for START STOP and EMERGENCY, I decided to use one simple toggle switch to replace the EMERGENCY. As for START STOP I will take it out from the Programmable Logic Controller (PLC) program. The new switch I call it RUN/STANDBY. This one switch will do both of those two switches job. The logic behind this change is, once the panel box is ON, all of the I/O basically are ready to operate. By having EMERGENCY and START STOP it just a matter of stopping the conveyors and pneumatic valve from operating only.

By installing RUN/STANDBY, it is set to RUN when machines are ready to be run and STANDBY while feeling up the conveyor with the moon cakes. During standby, the valve will be shut off meaning the packaging machine and auto feeder sachet machines can run as usual. Once all 3 conveyors (BCD) are full, then if the operator switch the control box to RUN, the valve will turn ON if there is a cutter signal received by PLC.

As to replace EMERGENCY switch, just turn OFF the panel box power supply to switch off all, or switch off the individual AC source at respective conveyors, or turn the switch box to STANDBY mode. One thing for sure, any of these action surely will stop the supply of moon cake to packaging conveyor. This is the revise ladder diagram.

ICTS-PLC first ladder diagram

After studying the manual for sometime, lastly I managed to come out with this one few days back. As you can see now I add the START STOP and EMERGENCY. To run the program, just turn ON the STARTSTOP while for emergency it is set to OFF by default.

Actually for the past one week, not much can be done for project ICTS due to company production planning suddenly change. Now they want to start the operation by 13 June 2007 which meant last week we have to take care other stuffs like machinerries services and many more. As a result the progress for the project was affected.