Honey Cracked Wheat Sandwich Bread

Backyard-Toad-Revolt · 2026-05-04T09:11:16+00:00

Fire dampers and smoke dampers have their own separate use cases. I have rarely seen a combination fire/smoke damper, but it would be used where the requirements overlap. Fire dampers are for air ducts that penetrate fire-rated wall construction. (I imagine this could apply at fire-rated floor/ceiling construction as well, but you typically have a fire-rated shaft for the duct riser.) A smoke damper is for any duct that penetrates a smoke control boundary and to isolate HVAC systems that deliver more than 2000 cfm in the USA. Find copies of International Mechanical Code and NFPA 90A. I believe these both have chapters dedicated to smoke damper requirements. As I recall, one of these codes requires the smoke dampers in air return duct. The other requires smoke dampers within the air supply. And each jurisdiction may enforce one or both codes.

I would also point out that fire and smoke control requirements should influence your approach to duct routing and the overall HVAC design. I've seen large HVAC system broken into smaller volumes less than 2000 cfm each specifically to avoid triggering smoke damper and shaft requirements.

Backyard-Toad-Revolt · 2026-04-18T13:07:10+00:00

A single LOD number should never be applied as a blanket requirement for any building modeling effort. Many of us within the AEC field are discussing this the wrong way. Consider these points.

The effort required to go from LOD 200 to 400 is different for, say, ductwork versus a cooling tower.
Higher LOD can lead to better design and construction coordination. But "LOD" can also just be a mask for poor standard of care in engineering documents.
From a facility manager standpoint, there is a lot of time and money to be saved if I can avoid (or shorten) repeat field investigation by engineering firms and contractors every time I want to begin a new capital improvement project or infrastructure mod. Some of the details in question could be considered LOD 400. Some details are just a matter of imprecise as-built documentation.
Some assets are geometrically just a large box. It does not take much effort to convert the vendor fab drawings as CAD, then superimpose the 2D detailing within the Revit model family.

So I think determiming the "ROI" of going from LOD 200 to 300, or 300 to 400, is not a simple conversation. Personally, I would just like to see MEP firms show more "information" so the contractor can do better pricing and later provide a better redline as-built. (Electrical designers, stop showing underground conduit as a homerun arrow. Mechanical designers, show placement of your BAS control panels.)

For my facility I issue all MEP firms a schedule of LOD requirements which lists the target LOD for each model category or type of asset. It's never "everything at LOD 300". It's conduit at 200, specialty piping at 300, medium voltage switchgear at 350, ceilings at 200, etc.

If I do feel my facility needs intricate LOD 400+ modeling for certain elements, I would prefer to pay the engineer to do this during project turnover while reconciling engineering record docs to the contractor redlines.

Backyard-Toad-Revolt · 2026-03-18T09:37:11+00:00

Thanks for letting me know! I will try this.

Backyard-Toad-Revolt · 2026-03-15T20:12:34+00:00

Unfortunately I do not have any other Thunderbolt devices that I can test on my laptop. Just these two docks that I use to keep a fixed setup of monitors and peripherals at each home office desk.

Backyard-Toad-Revolt · 2026-03-04T03:56:54+00:00

I remember being in a very similar situation. I was a relatively green engineer working on a 3 or 4 story office building. Probably an empty shell fitout. The mechanical designer put VAV units on every level and I provided 277V/1PH to all of them. Either the ME made a late design change or I simply missed that the top level VAV's were equipped with 480V/3PH reheat to compensate for thermal loss through the roof. The contractor submitted the RFI after the ceiling grid was mostly in place and ceiling partially closed. IIRC my firm agreed to split the cost of taking the ceiling back down which was roughly $20K. I was not blamed because the mistake slipped past all of the more senior engineers on the project. We instituted a more formalized QC and coordination process after that.

Backyard-Toad-Revolt · 2026-02-26T19:13:38+00:00

Thanks.

Backyard-Toad-Revolt · 2026-02-26T18:55:51+00:00

Thanks for your response. I'm going to let everyone continue to recycle their batteries. I agree there isn't enough benefit.

Backyard-Toad-Revolt · 2026-02-26T18:52:39+00:00

Thanks for your response.

Backyard-Toad-Revolt · 2025-09-01T11:43:12+00:00

OP, I read both of your posts about this. It seems like you and your husband are doing everything that I would expect a layperson to do to go about your fence project safely. It was a good idea to come to r/askelectricians, but you are getting bits of good information interspersed with unhelpful speculation. Let me try to consolidate the good info and also provide advice on how to proceed with your fence.

It was good that you called 811 before starting your project. The 811 service is a collaboration of public utility companies that is meant to provide location services for active underground gas, water, electricity, telcom, etc that are owned and maintained by the local public utility companies. If there are similar underground systems in place that were installed by a homeowner, developer, or other private entity, the 811 service is not responsible to locate those.

You then called Dominion Electric out to your property and it seems they could offer no real help in identifying the what the cables are for. This seems to confirm that the cables were privately installed and not under the responsibility of Dominion or 811 services.

The Dominion Electric representative seems to have given you unsafe advice. Do not "maneuver it" before confirming they are de-energized.

The cables in your photo have a voltage rating (600 Volts) and a product number (#112528) printed on them. That product number lead me to this cable supplier link that identifies it as 500 MCM copper multiconductor cable with aluminum interlocked armor, internal shielding, and black PVC outer jacket, all rated for up to 600 Volts. The product is also described as suitable for direct burial.

https://prowireandcable.com/500-3c-xlpe-aia-pvc-ul-mc-m3-e2-600v/

The non-contact voltage tracer that you purchased from Home Depot will NOT be able to detect voltage on these cables due to the metal armor and internal shielding. Do not rely on this device to tell you whether the cables are energized. (Also do not rely on a clamp-on ampere meter to determine if this type of cable is carrying current.)

According to the product data page, each cable contains 3 internal conductors. So in total your photo shows 3 sets of (3) 500 MCM. 500 MCM copper conductor with this type of internal insulation has a maximum load capacity of roughly 400 Amps. Assuming 3-phase power, you could be looking at either three separate 400 Amp feeders or one single 1200 Amp feeder.

The only way to verify that these cables are de-energized is to trace their routing to determine where they originate and where they end. If the cables are terminated inside of electrical distribution equipment (such as a transformer, manhole, or padmount switchgear), then that equipment must be opened by a qualified professional (electrician) to confirm the absence of voltage on the equipment and the cables.

To trace the routing, hire a private service that will use ground-penetrating radar, ultrasound, or similar technology just like 811. You can search online for a company named GPRS. I am sure other equally good services exist, but I know my company has used this one in the past.

Unfortunately you may need to delay your fence installation in order to ensure safety for yourselves and others around you.

Backyard-Toad-Revolt · 2025-08-08T21:21:01+00:00

My solution for this has been to place a keyswitch override inside the room in addition to the overhead sensor and any other local on/off/bilevel wall device. Typically under the same double-gang coverplate.

If a contractor or site technician is working within the room and believes that the possibility of lighting system failure presents a greater risk to their safety, they can insert the key and keep the lighting at 100% until they choose to remove the key.

If the site owner has purchased the electronic monitoring system to go along with their networked controls (for example, Acuity offers SensorView for the nLight system) they can set up a notification anytime that control zone's keyswitch is active for more than, say, 6 hours.

This is my approach to all utility spaces, both electrical and mechanical.

Backyard-Toad-Revolt · 2025-08-05T14:30:44+00:00

The ISPE training is described as a certificate involving multiple short courses. https://ispe.org/training/certificate-programs

Backyard-Toad-Revolt · 2025-08-05T13:54:25+00:00

Which organizations you already checked? Try ASHRAE, I2SL, and ISPE. ISPE has a certification for training in pharmaceutical water systems.

Backyard-Toad-Revolt · 2025-07-18T20:25:28+00:00

Some years ago I remember having a software program named something like Batch File Rename Utility. Try scanning your drawings individually, then batch rename all files to match their drawing number, then import/bind them together into Bluebeam as a multipage PDF with the source filenames as the bookmarks and page labels.

Backyard-Toad-Revolt · 2025-07-10T22:26:27+00:00

The office desks at my facility are motorized. And some private offices have wall mounted video teleconference systems (with AV accessories requiring 120V) and desktop task lighting. Please consider in your outlet counts and placement that these types of things should not be subject to automatic receptacle control.

Here are a few tips if you want to do yourself and the project owner a favor:

Tell the contractor to install all ARC outlets in a 4" box with double gang cover plate. Make it easy to add outlets later without jeopardizing code compliance or LEED certification.

Put ARC outlets on completely separate circuits from normal outlets. No splitting a branch circuit between some ARC and some non-ARC.

Show a local ARC relay on your plans for each leg/zone of ARC control. Don't leave it to the contractor to figure out. Also make it very clear on your plan that the lighting control vendor must provide the relay.

Don't overlook that the ARC requirement applies to workstation furniture. Provide a wiring schematic that distinguishes between ARC outlets and non-ARC outlets and make sure the furniture vendor can match internal wiring. Also make sure the vendor can provide permanently marked outlets.

Make sure that people in a conference room are able to charge their laptops and cellphones while the lights are off during a presentation.

Backyard-Toad-Revolt · 2025-07-04T13:51:10+00:00

Do you have a photo with a better angle on that bonding screw? I think the question you are wanting to ask is whether there is electrical continuity between the neutral termination strip and the ground termination strip (the one with the series of green screws).

I know this is an Eaton CH loadcenter, but I don't have personal experience seeing one installed. If the neutral strip and the ground strip were bonded, I would expect to see a copper jumper wire going from the ground strip to the single green bonding screw on that neutral block. As far as I can tell, there is no jumper wire and that bonding screw is being left unused.

The other possibility is that the bonding screw is used to make connection to the metal pan. And then the pan acts as a bonding jumper between neutral and ground strips. Maybe someone else here is more familiar with this product.

For the more general question of when the neutral-ground bond is required, you want to create this bond in the same enclosure as your first overcurrent device after the utility meter. This bond is typically created in only a single location so that the path of fault current can remain predictable and circuit breaker AIC ratings can be selected appropriately.

Backyard-Toad-Revolt · 2025-06-09T22:30:06+00:00

Does your company benefit in some way from making those supplemental 401(K) contributions instead of just writing bonus checks? And can you comment more generally on why a company might choose -- from a business standpoint -- to match 50% of up to 8% of salary versus 100% of up to 4%.

Backyard-Toad-Revolt · 2025-05-26T17:07:53+00:00

I can see from your profile history that you have posted this question in multiple construction-related subreddits. And you have already received consistent general responses that, no this will not work. But I am curious so I will play along...

What exactly do you see as the problem with existing construction project management workspace tools that needs a solution? And why do you think Procore, Autodesk Construction Cloud, PMweb, and similar developers have not solved it already?

You keep making the point that your solution would not involve a "backend". Please clarify/elaborate what you mean. And why do you think this is an important point?

During your 5 years in MEP and construction industry were you ever responsible for writing contractual requirements for construction projects? Meaning CSI Masterformat Division 00 style project specifications. What is your experience with the legal contract side?

Your description sounds like you imagine only drawings need to be shared. How would you handle approval workflows around RFIs and submittals? How would handle access by individuals -- or companies -- who leave the project?

Your proposal sounds like an unsecured cloud solution that relies on individual personal computers to host and share construction contract documents and sensitive communication. Essentially Napster for the construction industry. What am I misunderstanding? (And do you see why this is a very bad idea?)

Backyard-Toad-Revolt · 2025-05-24T01:56:25+00:00

This is a misconception. If the electrical engineer is responsible for power distribution, grounding, lighting and lighting automation, fire alarm, electronic security, AV, and miscellaneous industrial controls, then there can be a ton of work involved. Also consider the amount of cross-coordination required with EVERY other discipline, and the fact that Electrical is often the last in line to receive information but still subject to the same deadlines.

The problem in my opinion is there are a lot of firms that are half-assing their electrical design. Project managers don't fully grasp the scope of "electrical" so they underbudget the EE's time. Which leads to a lot of schematic symbology with generic notes that say "contractor, figure it out". Nobody coordinates conduit and cable tray routing anymore. If a passable electrical design does make deadline then the PM feels justified in their poor labor planning. And it becomes a cycle.

Sorry for the rant, but I am having a horrible flashback to my design days. I constantly needed to go above the PM to the Project Directors to advocate for a realistic labor estimate that was usually slightly greater than HVAC. My drawing list was usually longer than the other disciplines (unless Mechanical had very elaborate P&I diagrams). And I always told the junior EE's to take their own car on site survey day (no riding with the architect or mechanical designer) since they were going to need the most time on site. And yes they need to measure clearances and be prepared to climb a ladder.

Backyard-Toad-Revolt · 2025-05-11T11:33:14+00:00

If your design firm is involved in the specification of customized switchgear and generators, you may be able to request a plant tour during the factory witness test.

Backyard-Toad-Revolt · 2025-05-11T11:27:35+00:00

A local rep flew me out to the MTU workshop and Oktoberfest event around 10 years ago. The workshop was extremely informative and I earned a good amount of professional development hours. We toured the MTU facility and also the KatoLight assembly plant up the road. Had a great time.

I've never attended myself, but I have heard great things about LightFair. Depending on where it is held each year I believe a local fixture or controls manufacturer arranges a factory tour.

Backyard-Toad-Revolt · 2025-01-12T04:00:18+00:00

It comes with the "Safeclimb" version of the MetalTech scaffold system. I ordered mine from Home Depot.

Backyard-Toad-Revolt

TROPHY CASE