Dangerous wiring habits.

[abwiz]

I have to agree with russrmartin...

If you look at the NFPA 79 Section A.3.2.2, you will find the definition of AHJ.

 

[kamenges]

Generally, I believe in the US the authority having jurisdiction would be the local government agency responsible for approving installations. This is why UL approval is not universally required in the US. Most local governments don't require it. In addition to the areas identified by Leon I know that the city of Chicago and several of the surrounding cities require UL approved installations as well as Los Angeles and several of the surrounding communities. However, in my area UL approval is not required unless it is a specific customer request. The local codes do not require UL approval of control installations.


Keith

 

[TConnolly]

All arguing aside, addressing the immediate problem of the OP: You have what you have and you need to render it safe. First off, place a warning label on the outside of the cabinet. Inside the cabinet place a warning label on every bottom fed contactor, CB, or circuit block. If necessary cut a small sheet of plexiglass and place it on standoff over the devices with a warning lable on the plexiglass. It may not be realistically feasible to correct the problem by rewiring.

 

[ndckevin]

All wiring is to be right to left and top to bottom. Neat and workman like.

 

[milmat1]

INTERESTING !!

We build million dollar machines, And none have ever been inspected by anyone.
It is an Engineered product. And inspection is not required.
All componants being CE certified doesn't make the box CE certified. I suspect the same is true for UL listing ???
Because we build the panel and box ourselves they are not certified or listed...??

 

[dogleg43]

The company I work for designs and builds custom control panels for all types of industry. Our panel shop is UL approved. When we need a UL sticker on something we have to call the UL office and a person comes out to verify everything is either UL approved or UL recognized (another long boring subject).

Normally the customer has a specificatio and the panel is built to it. If they require it to an UL approved panel then it normally costs quite a bit more because of the paperwork and extra engineering involved.

 

[curlyandshemp]

I had a problem earlier today with a motor. I opened the panel and started looking at the controls.

I noticed the voltage was not being fed into the top of the fuse block, overload, and contactors. It was being fed into the top, or bottom, which ever was closest.

This doesn't seem safe to me, especially with the fuse block, since when you pull the top of the fuses, the fuses can be exposed while the bottom are still connected to the voltage. I can just see a maintenance employee opening the fuse block while quickly trying to fix it, and touching 480VAC.

Is there anything in the NEC about this type of thing? (Even if there isn't, I personally am rewiring that particular panel to make it safer)

I guess that is why now most DIN rail mounted fuse holders isolate both the line and load sides of the fuse when pulled to the open position

Ian

 

[Jimmie_Ohio]

The company I work for designs and builds custom control panels for all types of industry. Our panel shop is UL approved. When we need a UL sticker on something we have to call the UL office and a person comes out to verify everything is either UL approved or UL recognized (another long boring subject).

The file for "Industrial Control Panels" is UL508. Additionally, you can only use components that are "listed for their intended use" to get the overall panel approved. EXAMPLE: You cannot put a UL labelled toaster in a control panel and glue the handle down to keep the panel's interior warm and dry.

There are also ways to use UL rocognized components or both non-listed AND non-recognized components, provided the application meets certain criteria and is added to your specific UL508 file. Example, a custom printed-circuit board (low voltage) may need to be fed by an particular power supply in turn fed by a GFCI breaker.

 

[geniusintraining]

... EXAMPLE: You cannot put a UL labelled toaster in a control panel and glue the handle down to keep the panel's interior warm and dry..

So if I just screw the handle down with some self tapping screws and not use the glue, that would be ok

 

[Tark]

Tharon –

There is nothing in the NEC that says that the Line must be connected to the top of the device. But I’m fairly sure that your installation does violate the NEC.

NEC 110.3(B) – Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

If you obtain the manufactures instructions on your contactors and overloads you will see that Line is connected to L1, L2, L3 on the contactor and the load is connected to T1, T2, T3. You will also see that the Load is connected to T1, T2, T3 on the overload. So if in your installation the Line is connected to T1, T2, T3 then it would be in violation of the NEC because it is not installed according to the manufactures instructions.

Your installation might be in violation of another part of the code. If I understand your post correctly, you are saying that in some cases the Line is going to the overload, which is connected to the contactor, which is connected to the fuse block, which is finally connected to the motor. If this is the case then it is a violation of NEC 430.51. The fuse (motor branch-circuit short-circuit and ground-fault protection) must be connected to the Line first. The fuse is meant to protect the motor conductors, motor, and motor control apparatus. If your Line isn’t going to the fuses first then the fuses can’t be protecting the motor control apparatus, hence a violation of the NEC.

I’m glad you noticed this error in the installation and didn’t get injured. I often forget there are a lot of boneheads out there who do stupid things because of convenience or laziness.

 

[Tharon]

Actually, it does go Fuse, Overload, Contactor.

But ya, the Line does go into the T label terminals and the Load is on the L labeled.

I guess I was over-cautious about the fuse holders. They do remove the entire fuse (top and bottom) when in the open position, but I was just worried that if it was partially open, that the bottom of the fuses might still be touching.