Question

MEMO

From: The Boss of the comapany

Subject: New Internet Cable Tension Machine installation Issue

Action: Your recommendation with detailed analysis and guidelines are required.

HINT: The question is worded like a businessman would write to you. There is more information than you need, ignore the fluff and focus on the objective. You should be able to do this in 10 minutes.

I received an urgent call this afternoon from our senior field service team leader Chuck R onboard the Japanese vessel K1. The vessel is dedicated to Internet cable installation in the ocean. This field service team is currently in charge of the installation of our new tension machine onboard the vessel. Chuck has indicated that they are in the final testing stage for our customer final acceptance test of the entire system. He is very stressed because this final acceptance test approval is tied to about $2.5 Million dollars payment. He needs our support.

Chuck has indicated to me that during the final test, the system computer screen (AKA Man Machine Interface, MMI) that is connected to the system controller that displays all the system parameters to the operators, indicates the correct tension up to the maximum rating of the machine of 100 KIP and was calibrated to this rating. The system controller has a 12-bit ADC resolution. However, when the system testing exceeds the machine rating, the MMI displays crazy tension numbers. Normally, the system MMI should display 1 KIP resolution.

In addition, Chuck told me that our new programmer on the team, Roger has diagnosed the problem and indicated that the load cells needs to be upgraded to higher capacity load cells. This is of course a showstopper. New load cells units cost only about $5000, but the helicopter cost is about $60,000. Chuck is not sure about the electronics and the digital issues but he thinks that no additional mechanical engineering or manufacturing is needed in case we decide to upgrade. We still need to check with the entire engineering group. However, he is sure that each load cell is connected to a signal conditioning electronic card that outputs 0-10 DC volt to the system ADC. Each card has adjustable knobs, one for zero percent and the other for span (100%).

As you know we are all off for the holidays next week, however I will dispatch the entire engineering group back to the office if I have to, but I need your analysis before I do that since you’re the only engineer on the premises today.

Chuck also indicated that Roger told the customer to apply 0-100 KIP force on the machine while he was calibrating the controller program to display the correct reading.

Our tension machine capacity is rated at 100KIP. However, our mechanical and manufacture design has 200% safety margin, we must not operate at that upper limit of course, but we should be able to operate and display above the machine rating within a reasonable limit. Our standard is twenty percent above the rating.

FYI, the machine has two load cells (SPWE-CA-50K) installed to measure the total tension. One installed on the starboard side and the second installed on the port side of the machine. Their total readings represent the total tension on the machine.

I included the load cell manufacture link below.

I need your recommendation with detailed analysis and guidelines to the field service team.

https://www.800loadcel.com/load-cells/pancake-shear-web-load-cells/spwe.html

Answer 1

You should write in this ,

I received an urgent call this afternoon from our senior field service team leader Chuck R onboard the Japanese vessel K1. The vessel is dedicated to Internet cable installation in the ocean. This field service team is currently in charge of the installation of our new tension machine onboard the vessel. Chuck has indicated that they are in the final testing stage for our customer final acceptance test of the entire system. He is very stressed because this final acceptance test approval is tied to about $2.5 Million dollars payment. He needs our support.

Chuck has indicated to me that during the final test, the system computer screen (AKA Man Machine Interface, MMI) that is connected to the system controller that displays all the system parameters to the operators, indicates the correct tension up to the maximum rating of the machine of 100 KIP and was calibrated to this rating. The system controller has a 12-bit ADC resolution. However, when the system testing exceeds the machine rating, the MMI displays crazy tension numbers. Normally, the system MMI should display 1 KIP resolution.

In addition, Chuck told me that our new programmer on the team, Roger has diagnosed the problem and indicated that the load cells needs to be upgraded to higher capacity load cells. This is of course a showstopper. New load cells units cost only about $5000, but the helicopter cost is about $60,000. Chuck is not sure about the electronics and the digital issues but he thinks that no additional mechanical engineering or manufacturing is needed in case we decide to upgrade. We still need to check with the entire engineering group. However, he is sure that each load cell is connected to a signal conditioning electronic card that outputs 0-10 DC volt to the system ADC. Each card has adjustable knobs, one for zero percent and the other for span (100%).

As you know we are all off for the holidays next week, however I will dispatch the entire engineering group back to the office if I have to, but I need your analysis before I do that since you’re the only engineer on the premises today.

Chuck also indicated that Roger told the customer to apply 0-100 KIP force on the machine while he was calibrating the controller program to display the correct reading.

Our tension machine capacity is rated at 100KIP. However, our mechanical and manufacture design has 200% safety margin, we must not operate at that upper limit of course, but we should be able to operate and display above the machine rating within a reasonable limit. Our standard is twenty percent above the rating.

FYI, the machine has two load cells (SPWE-CA-50K) installed to measure the total tension. One installed on the starboard side and the second installed on the port side of the machine. Their total readings represent the total tension on the machine.

I included the load cell manufacture link below.