What Field Modifications Are OK?

C

CoolWill

Senior Member
Location
Alabama
Occupation
Electrical Contractor
I don't make it a secret that I don't mind field modifying or even building equipment. I am a craftsman and I think I have the knowledge to safely carry out such things. But many purists take issue with that. And I do understand why because I've seen some real stinkers out there. In my experience, I've never really been called on it because I do good work and the inspectors and engineers I've worked with are practical and reasonable people, for the most part. For example, I built a controller to interface a donut fryer to a vent hood and fire suppression system using off-the-shelf contactors and relays. The inspector noticed it was field built, and asked me a bunch of questions, and looked but accepted it.

What kinds of field mods do you guys generally make and/or find acceptable?
 
CoolWill said:
What kinds of field mods do you guys generally make and/or find acceptable?
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Same as you. I think that control wiring is the most fun and interesting aspect of our work. I enjoy the challenge of translating the operational requirements into a functional circuit.

I have wired many new and existing suppression systems, and have never had the equipment and components I used brought up, just confirmed that the system functions correctly.
 
ActionDave said:
We used to make our own well pump control boxes and ansul system controls at my old shop.

I've never hesitated to modify something, swap out a part, or add a relay when needed. When a comment about, "violating UL listing" is expressed the point where I stop listening begins.
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I still listen, just don't hear as well.

I am inclined to think a panel builder could put together a better product, but can they do it today when I needed it done yesterday because the customer wanted it last month but forgot to call until yesterday?
A couple PBs, a relay, a motor starter. That's about it, and you should be calling someone else.
 
ptonsparky said:
A couple PBs, a relay, a motor starter. That's about it, and you should be calling someone else.
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That's usually all you need to make something that they want to work better or work the way they want it to. Time delay relays are like caramelized onions with dinner, add them to something and everything gets better.
 
When I read the thread title "Field Modifications" I thought it meant drilling holes in metal enclosures, rewiring some equipment, adding a relay, or cutting wireways to fit, etc. Should we consider building an industrial control panel to be a field modification?
 
infinity said:
When I read the thread title "Field Modifications" I thought it meant drilling holes in metal enclosures, rewiring some equipment, adding a relay, or cutting wireways to fit, etc. Should we consider building an industrial control panel to be a field modification?
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It in the same vein. Some discussions recently were about rewiring control panels for better functionality etc. But other types of modifications are game too. For example, someone mentioned finding LED retrofits powered by using the old MH ballast as an autotransformer. I have seen it as well. It's interesting but is sure to raise the hackles of certain types.
 
infinity said:
When I read the thread title "Field Modifications" I thought it meant drilling holes in metal enclosures, rewiring some equipment, adding a relay, or cutting wireways to fit, etc. Should we consider building an industrial control panel to be a field modification?
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That was my thought too. I don't consider getting a j box and putting in some contactors and other stuff in it to accomplish some task a "field modification"

Regarding modifyijg equipment, I am quite libertarian on the subject. I am vehemently against the dumbing down of the trade to where we are just "installers", and furthermore, I have become pretty disappointed and disillusioned with the listing and product standard process to the point that I don't really trust those people to accomplish anything meaningful.
 
electrofelon said:
I am vehemently against the dumbing down of the trade to where we are just "installers", and furthermore, I have become pretty disappointed and disillusioned with the listing and product standard process to the point that I don't really trust those people to accomplish anything meaningful.
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I agree. Many times over my career we had to field engineer and build something. I remember doing a 33 story building and the electrical field drawings stopped about the 20th floor because our engineer quit. We ended up finishing the job with just the men in the field which included installing and wiring up remote control motorized circuit breakers, phase monitors, and all sorts of other nonsense. At the end of the job they ended up asking us for wiring diagrams for all of the field modifications. I ended up giving them some stuff I drew with a ruler and a pencil that resembled scribble on a bar napkin.
 
I put together a portable 3Ø panel board once. The guy wanted a panel with a pin & sleeve connector to connect to a generator. Then he wanted receptacles for his equipment to plug into. I used a Hoffman box to mount the receptacles in. I put breakers in and wired the receptacles to the breakers. The receptacles had weatherproof covers. This was all 480V.
The whole assembly was put on a cart to move it where it was needed.
 
infinity said:
When I read the thread title "Field Modifications" I thought it meant drilling holes in metal enclosures, rewiring some equipment, adding a relay, or cutting wireways to fit, etc. Should we consider building an industrial control panel to be a field modification?
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I have no qualms about replacing an AB pushbutton with a CH, Eaton or a Furnas, if that is what I have on my truck. Adding a days down time for the customer and/or 100 miles of travel time is bonkers. A good chance I would have added a couple CC fuses while I was at it.
 
As a GC/framer as well as an electrical contractor, I’ve always found it a bit odd that we take pieces of lumber of various grades and conditions, with various irregularities and defects, cut them, shape them, nail, glue and screw them together, to build a 3 story building that will have dozens of people living and working in it, but if I take a bolt off a buss in the back of a piece of switch gear, I have to have a field engineer sign off that I put the bolt and nut together the ”right” way. 🙄🙄

Sounds like horse byproduct to me…….
 
Seven-Delta-FortyOne said:
As a GC/framer as well as an electrical contractor, I’ve always found it a bit odd that we take pieces of lumber of various grades and conditions, with various irregularities and defects, cut them, shape them, nail, glue and screw them together, to build a 3 story building that will have dozens of people living and working in it, but if I take a bolt off a buss in the back of a piece of switch gear, I have to have a field engineer sign off that I put the bolt and nut together the ”right” way. 🙄🙄

Sounds like horse byproduct to me…….
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Yeah, especially considering how horrendous the vast majority of framing is. I swear my sister could do a much better job than most of what I see
 
And yet, for all that, we don’t have an epidemic of building collapses in this country. And believe me, I’ve seen some framing that blew my mind.

Closest we got was a spate of balcony collapse, which honestly amounted to a handful, and those were more of an issue on the design side than an execution issue.
 
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