HEL Plc

[petersonra]

There are a number of Informational Notes that refer you to other code sections. Sure the notes themselves are not enforceable but that has NOTHING to do with the enforceability of the referenced sections.

except in this case article 725 specifically states that only those parts of chapter 3 sthat are referenced in article 725 apply.

 

[tom baker]

There are a number of Informational Notes that refer you to other code sections. Sure the notes themselves are not enforceable but that has NOTHING to do with the enforceability of the referenced sections.

And the IN in 300 3 C 1 is a helpful hint to look at the rule in 725. Its not required at all, but I have run across many many electricians who will mix low voltage class 2 with 120 as the class 2 has 600 volt insulation.

 

[don_resqcapt19]

except in this case article 725 specifically states that only those parts of chapter 3 sthat are referenced in article 725 apply.

I stand by my statement that 300.17 is a performance requirement, that you must comply with, and the xxx.22 rules are the prescriptive rules that let you meet that performance requirement.

 

[ctaylo360860]

For the 50+ plcs I installed, for the field wiring I used 14AWG THHN, analog inputs were Belden 1032A, power limited tray cable. if you want 16 AWG, its a TFFN type but the 14 is readily available and more tolerant on installation. You could run a multiconductor PLTC to a junction box and then transition to lower pair count or 14 AWG, but this means more splices, and more wire labeling.
We had a Greenlee cable cart and would load multiple rolls of 14, put a wire number on the spool and one on the wire end and pull many at once.
Pulling went really fast, the slow part was labeling, dressing and landing each wire. I used a Brother PTE-300 industrial labeler with heat shrink labels, looked great when all done.
Mark up your drawings as you go. I used the fuse # PLC input as the wire number. FU-1 and 2-4 would be card 2, input 4. Ideally you want a different number on each wire, so if you have two wires on Fu-1, then its FU-1-1 and FU-2-2Thanks for the tips! I think that’s gonna be the plan, but checking with manufacturer that the terminals Definitely buying the label maker!

Thanks for the tips! I need to confirm 14 fits inside under terminals provided by plc company. That labor maker is sweet I’m definitely getting one!

 

[ctaylo360860]

Does anyone see any issues with using emt raceways? This is at a outside wet fertilizer plant, the liquids should be contained inside the system… we use to have an blender with an open top that sat outside making the metal corrode, but is now removed. I had planned to do pvc, but I feel like emt maybe faster, and less restriction on the wires were pulling….

 

[ctaylo360860]

Does anyone see any issues with using emt raceways? This is at a outside wet fertilizer plant, the liquids should be contained inside the system… we use to have an blender with an open top that sat outside making the metal corrode, but is now removed. I had planned to do pvc, but I feel like emt maybe faster, and less restriction on the wires were pulling….

I have read 358.10(b), 358.10 (c) - this means if I use met in corrosive environment everything from tubing to all means of support need to be galvanized steel? and 358.12 (2) does this basically mean I can’t paint the tubing to protect it?

 

[tom baker]

PVC outside is hard to run, has to be supported much closer than EMT, and there are issues with expansion.
Any metal raceways outside will corrode. Also need to consider what type of boxes you are using, FS, bell boxes, etc.

 

[ctaylo360860]

PVC outside is hard to run, has to be supported much closer than EMT, and there are issues with expansion.
Any metal raceways outside will corrode. Also need to consider what type of boxes you are using, FS, bell boxes, etc.

I ended up changing my mind and going all pvc… yeah I got a ton of expansion joints snd plan on over strapping everything…I talked to my uncle and he mentioned aluminum, I’ve never seen or worked with any of it but maybe that could of been another possibility? I’d like to go pvc coated rigid, but because of my time constraint that may be the issue there. All my boxes are going to be pvc, and I believe the same with enclosures from Kahler.

 

[tom baker]

PVC can look good if time is taken with the bends and supports. I find for exposed work its slower than EMT