QUESTION

 

 

ANSWER

 

About the Problem

“A meter with a very nice color screen is designed to measure, ohms, volts, or amps, depending on the setting and connections. The meter works fine for ohms and volts, but we can’t seem to get any data when we try to measure amps.”

Manufacturing processes that include the usage of electronics equipment like weld machine, solder, etc. also need a huge amount of voltage capacity to support the process. But, there’s always a critical limit of the voltage beyond which the process can become a damaging instance. On the other hand, if the amount of voltage is below that critical limit, it becomes difficult to smoothly channel the process. Hence, a fine balance on the thin line is much required.

Introduction

The above-mentioned problem is quite commonly seen in many multi meters. A multi meter is a device which is connected to the voltage input rod and shows readings on a screen about how much voltage or current input is given. It is there to control the input.

“A multi meter is a device which is connected to the voltage input rod and shows readings on a screen about how much voltage or current input is given.”

The problem explained in the assignment is quite a common issue with multi meters. There can be many reasons for the multi meter to behave in such a manner. For this assignment I’ll list ten of them in various categories such as human error, manufacturing error, etc.

Human Error:

1. Lose connections: There are many wires and leads which are interconnected between the multi meter and the device working to know the electrical readings. A lose connection can result in certain failure.
2. Zero Error: Zero error is present in almost every metrological and electrical device that takes readings from outer sources. For example, if the default reading on the multi meter is 2 amps, it will always show an increased value of current by 2 from the original value.
3. Charging issues: Multi Meters use batteries to stay connected with their process. Once the cells are discharged, the user must recharge them again.

Manufacturing Error:

1. Faulty Fuse: Due to heavy voltage or current, which is an overload for the multi meter specification, the device is not able to take the excess load and before damaging the device it transfers the load to fuse. Fuse are specifically designed for a particular load. Due to over load the fuse burns.
2. Faulty Display: Sometimes due to discharged battery, or due to abrupt fall of the devices from a certain height, the display loses its control and doesn’t give a clean look of the readings.
3. Power issues: The electric power rod is not able to supply enough current to show on the screen. Another issue which is neglected many times. The electric power rod which cannot deliver or use enough power, which is required to show the readings on the display.

Mechanical Error:

1. Software issue: As multi meters are digital reading devices, they have motherboard built inside itself. There are many devices in which the motherboard has pretty loosely soldered integrated circuit chips on its face.
2. Physical Damage: Due to abrupt handling of the multi meter or careless utilization, the internal parts might get broken.
3. Settings: There are inbuilt setting that are needed to be reconfigured when changing the multi meter usage from device to device.
4. Short Circuit: The cell voltage reading drops to 0 when the wirings inside the multi meter gets short circuit.

Mind map

FAILURE MODE ASSESSMENT AND ASSIGNMENT

Event/sheet	Hypothesized failure cause	Assessment	Assignment
1	Lose Connections	Likely	The lose connections can be manually checked and should be plugged properly. If the probe leads are not fitting well in the plug junction, they should immediately be replaced.
2	Zero error	Likely	Either the zero error can be reduced from the taken value during the calculations.
3	Charging issues	Likely	The user should keep the batteries charged when they are discharged.
4	Faulty Fuse	Likely	Do not use the multi meter where there is a possibility of getting fused.
5	Faulty Display	Likely	Reconfirm if the display is working and the readings are not coming broke. If so, please check the display wiring inside.
6	Power Issues	Likely	Check the electrical power rod. If it’s not supplying enough power, it needs to be replaced.
7	Physical damages	Likely	The user should keep it with care as there are delicate parts inside. A proper leather cover for the multi meter will also do.
8	Settings	Likely	In settings, contrast is an issue. If the contrast is very low or high, the readings will not be visible to the user.
9	Software issues	Likely	The motherboard should be properly soldered with the integrated chips. Otherwise, the soldering issues can lead to the software damages.
10	Short circuit in cell voltage, dropping the cell voltage to zero.	Likely	Make sure that the multi meter is not getting over heated and aiding to the short circuit condition inside the device.

References

1. https://www.goconqr.com/
2. https://www.researchgate.net/post/Why_can_I_not_measure_current_and_voltage_both_in_parallel_by_using_two_multimeters
3. https://www.circuitspecialists.com/blog/dmm-troubleshooting-repair/