Hello all

I have been an electrical engineer in manufacturing for the auto industry for 10 years and 3 years in the pharmaceutical industry. Recently I have been asked by the head of our companies Quality Assurance department to run a qualification analysis(C&Q) on the 120VAC wall plugs in one of our rooms. They want to know what Voltage and what Current the wall outlet is outputting without any devices plugged into them. This would verify the wall outlet meets the electrical statics required by the machines. In the pharmaceutical industry it is very common to have to verify every last detail of every thing with calibrated equipment.

However I have never been asked to verify the output current of a wall receptacle while nothing is plugged into it. This QA person will not budge they say I need to measure the current in the wall receptacle with a calibrated multi meter, They "have been in the pharmaceutical field for 20+ years and have never had anyone say they cannot measure current from an empty 120VAC wall receptacle".

Am I missing something here? is there some way to measure the current in the way they are asking? Does anyone else have experience with this in the pharmaceutical industry?

Thank you in advance for any help

 

How do you intend measuring a current when no load is present?
Does not make much sense?
What qualifications does the QA person have?
Possibly they mean measure/test it at the rated current capacity ??

 

Welcome to AAC!

This QA person will not budge they say I need to measure the current in the wall receptacle with a calibrated multi meter, They "have been in the pharmaceutical field for 20+ years and have never had anyone say they cannot measure current from an empty 120VAC wall receptacle".

How can you possibly measure current from an outlet if you don't apply a load?

Wouldn't it be more important to apply the rated breaker load at the far end of a run to see how much line voltage droops?

 

Welcome to AAC!
How can you possibly measure current from an outlet if you don't apply a load?

Wouldn't it be more important to apply the rated breaker load at the far end of a run to see how much line voltage droops?

 

They have a Masters Biology and a Masters in Chemistry and they have been in charge of Qualification/Calibration/Verification for pharmaceutical companies such as Pfizer for 20 years, I do not doubt their qualification and respect the individual which is why this is so frustrating for me.

I have suggested checking for droops or verifying the current when the machine is plugged in but they are dead set on knowing the current running through the outlet without anything plugged into it.

I am tempted to just blow the companies expensive calibrated multi-meter up by measure current from hot to neutral

I was hoping there is some specific test they do for pharmaceutical verification that I am not aware of

 

I would ask the individual for some clarification and explain that in-and-of itself, that the statement in the general sense of normal testing, it does not make sense.
Some kind of possible leakage to GND etc??
Ask for a reference to a particular standard regarding pharmaceutical requirements.

 

They have a Masters Biology and a Masters in Chemistry and they have been in charge of Qualification/Calibration/Verification for pharmaceutical companies such as Pfizer for 20 years, I do not doubt their qualification and respect the individual which is why this is so frustrating for me.

I have suggested checking for droops or verifying the current when the machine is plugged in but they are dead set on knowing the current running through the outlet without anything plugged into it.

I am tempted to just blow the companies expensive calibrated multi-meter up by measure current from hot to neutral

I was hoping there is some specific test they do for pharmaceutical verification that I am not aware of

It looks like you're going to have to figure this out or resign. Personally, when confronted with such idiocy I'd resign immediately if not sooner.

 

Admit to them that you unaware of the procedure required to perform the test. Typically, such tests have associated procedures, as part of the qualification. Be open, as there may be a learning opportunity.

 

The method of measuring the open circuit current is simple: First, connect one meter probe to the line side with the other probe in the air. Record the reading. Then connect to the neutral side and the air in a similar manner, record that reading. Then add the two measurements and that is the total current with nothing connected.
Caution is required to avoid a shock from the probe connected to the air,so follow standard safe measuring procedures.
Keep in mind that you are measuring current into an open circuit and so the numbers are likely to be very small, THAT is OK.

 

The method of measuring the open circuit current is simple:
Keep in mind that you are measuring current into an open circuit and so the numbers are likely to be very small, THAT is OK.

Do you have to turn around three times before you take the measurement?

 

Do you have to turn around three times before you take the measurement?

Max, no!! Consider that the process I described certainly will deliver exactly the demanded information, which is"leakage current into air", It is sometimes useful to let fools have their way, and when it can be done in a manner that actually does conform to the demanded process, it can save a lot of wasted intellect trying to convince a fool.
The data gathered does need to be presented in the correct format, the same format used to report the current used by other items.

 

The data gathered does need to be presented in the correct format, the same format used to report the current used by other items.

Also Include some air quality information, atmospheric pressure, altitude etc, which may affect the reading ! This will be sure to boost your apparent knowledge of the required information !
(Add the cost to the submitted bill for the assessment)!

 

Thank you for the responses guys, I am glad I am not crazy in thinking that this was not really possible/practical.

When I asked what procedure they used in the past I was referred to this article on, all about circuits
https://www.allaboutcircuits.com/textbook/experiments/chpt-2/ammeter-usage/#:~:text=Introduction%20to%20Measuring%20Current&text=It%20is%20measured%20in%20the,also%20go%20through%20the%20meter.
Which further backed up what I was trying to tell them.

Measuring the room temp/humidity is part of the qualification protocol already.

The individual decided to hire an outside company to get this current reading. I requested to be present to learn how the outside company does it. So far they have not found a company that does this kind of thing.

 

It will be very interesting to see if they can locate an HONEST company that is willing to do such a un-needed test proceure.

What equipment was used to measure the current drawn by the devices that have been checked?
I have a very good ammeter package that includes an adapter that plugs into an outlet and then the item to be measured plugs into it. A similar adapter setup could be purchased to use with the present meter. Then it would be a simple matter to plug the adapter into each outlet and record the reading.
Using that identical procedure to measure the no load current should be satisfactory.
I would rent you my meter except that it is an analog meter not recently calibrated to NBS standards.

 

. So far they have not found a company that does this kind of thing.

Wow that is surprising!
I would volunteer, but I don't think they could afford me, it takes a natural gift to read the elements this way and plot them in order for a layman to understand.

 

It sounds simple to me. I would measure the current the same way I do in any other device. Put an ammeter between the power lead and the connector to the socket.

 

The test procedure would be exactly the same as it is for testing actual equipment, except that the connection will be to "thin air", and the reading will be zero, within the stability of the measuring device.
Use exactly the same procedure, but connecting to nothing will require some effort to avoid laughter or smirking.

 

Hello all

I have been an electrical engineer in manufacturing for the auto industry for 10 years and 3 years in the pharmaceutical industry. Recently I have been asked by the head of our companies Quality Assurance department to run a qualification analysis(C&Q) on the 120VAC wall plugs in one of our rooms. They want to know what Voltage and what Current the wall outlet is outputting without any devices plugged into them. This would verify the wall outlet meets the electrical statics required by the machines. In the pharmaceutical industry it is very common to have to verify every last detail of every thing with calibrated equipment.

However I have never been asked to verify the output current of a wall receptacle while nothing is plugged into it. This QA person will not budge they say I need to measure the current in the wall receptacle with a calibrated multi meter, They "have been in the pharmaceutical field for 20+ years and have never had anyone say they cannot measure current from an empty 120VAC wall receptacle".

Am I missing something here? is there some way to measure the current in the way they are asking? Does anyone else have experience with this in the pharmaceutical industry?

Thank you in advance for any help

My surmise is that they are using imprecise language because they don’t know the difference. They could mean:

1. The voltage at the outlet
2. The capacity and functioning of the breaker
3. The proper wiring of the outlet (Land N properly connected and ground present)
4. Or even something surprising like the operation of a GFCI/RCD

I think I would ask them for an example report which might reveal the nature of the test(s). “I am not sure what it is you need certified but if you can share an example report I’m sure we can figure it out.”, &c.

 

Simple. Present your results with supporting documentation. Show photographs of your voltmeter and ammeter under no-load conditions.

 

All of those suggestions might work, but it is also likely that you are up against one who will not acknowledge that there is anything that they do not understand completely. The ten foot tall ego attached to some slight authority is rather a pain to deal with.
Worse, demonstrating that they made an error may make an enemy out of them. THAT is a serious error to make.