19 Mar PQ Surveys, Part 2 – Checklists
Over the next few months, iGround will be presenting a series of blogs to address the methods of approaching the various levels of Power Quality site surveys, depending on the location to be investigated.
This installment focuses on pre-survey checklists.
So…you field a call from someone that is experiencing an electrical problem (possibly grounding/bonding) and they need you to help them find out what it is. After a couple minutes of gathering background information, it’s not a stretch to see how some people that start out doing electrical investigations soon feel that they’re in over their head. There are a number of reasons for this.
- Most customers tell us their version of what the problem by describing it with their unique vocabulary (e.g., one customer described how he had ‘transients with harmonicas’. My response of ‘Do you mean hobos with mouth organs or something else?’ was met with ‘I’m not sure’).
- You’ve never been to the site.
- You don’t know the ‘players ‘involved.
- You’re not familiar with the equipment affected.
- The customer is usually only willing to pay for ‘one day’.
- They want you to locate the problem,
- …don’t shut anything off…
- …and need recommendations ASAP!
Yeah….so, like…it’s a challenge.
Best Place to Start
You can have all the confidence in the world as an electrical system investigator, but you still need to go in with a plan. Some of our customers think that we hang up the phone, don our superhero cape, and go solve the problem. (That only works in a very small percentage of scenarios.)
I recommend that you get the customer involved right off the bat by giving them a pre-survey checklist and making sure that someone knowledgeable about the problem has a hand in filling them out.
The ‘High-Level’ Checklist
This checklist is useful to finding out exactly what may be going on. Often, our customers don’t know how to describe the problem they’re experiencing so we give them a checklist that may have some key phrases on there.
>> High-Level Checklist (PDF)
See Checklist #1 for example. We want customers to focus on the left side of the page so, I recommend taking out any references to ‘WG’ (Wiring/Grounding), ‘VQ’ (Voltage Quality), or ‘HM’ (Harmonics) if you think they’ll misinterpret what/why you’re asking these things. Time of day/day of week correlation will be important for repetitive issues. Once this is filled out, then you can focus on the supplemental checklists.
The ‘Wiring/Grounding’ Checklist
This checklist is one that the customer can give their electrician or electrical maintenance person to fill out, especially if they’ve answered ‘YES’ to any of the questions on the ‘High-Level’ Survey checklist where ‘WG’ is likely. But, these items are the ones that would need to be checked anyway. So let those that are more qualified (electricians) do the work and have a chance to fill it out.
But, let’s state the obvious…
Without question, this author has mentioned AD NAUSEUM that the majority of ‘power problems’ and equipment operational issues are Wiring and Grounding. And, if that’s the case, don’t I run a financial risk for my company by having someone ELSE do my job and possibly find the problem before we had a chance to be the hero? Perhaps…
But, the customer is never going to forget who helped point them in the right direction in the first place. And, if they run into a future problem where that checklist doesn’t help, guess whom they’re going to call next…? Several of our clients have a long relationship with us now as a result of that strategy…everyone wins.
Voltage Quality/Harmonics Checklist
I struggle to write anything here that would accurately encapsulate the issues related to these two subjects. Having a checklist that could be ‘thorough’ would likely be 12-14 pages of questions. But this is a good start.
If you recall from Part 1 of our blog, a Level 2 survey is where the voltage quality survey would take place. This checklist might be helpful for the customer to fill out so you definitely want them to have it. But, you might want to have it handy for yourself after your Level 1 survey since your impression of the site’s voltage quality may change based on some other data you might gather.
Pre-survey checklists help gets the customer involved in properly identifying where to start your survey. In some cases, they can use it to solve their own problems. In that case, it’s invaluable as a customer-service tool. But, BEWARE…….if, for any reason, they can’t/won’t/don’t fill it out, you better have an idea of ‘what’ to look for and ‘how’ get that information…before you get there.
In our next blog, we are going to look at a Grounding Electrode System investigation. A lot of people start at this area of electrical distribution, but that doesn’t always correlate into success. Nonetheless, we’ll talk about where to place priorities as to what to look for and how to perform certain tests.