What Does an Orange Wire Do in an Electrical Control Panel?

=============================

▶ Check out the full blog post over at

=============================

Within the panel, we have a number or orange-colored wires. You may wonder what these are for, as we’ve already heard of the blue and white wires connected to the PLC.

Well, what these wires are for is to give power to devices when the main switch or panel isolator is in the OFF position.
“Why would we want to keep things on when we’ve turned the power off?” I hear you ask! “Isn’t that dangerous?” Well to put it simply, NO!

If we try to understand the different colored wires in a panel, this will help us to understand why those that are colored orange are suitable to work even when the main switch is off.

The colors of wires in panels are required by law to follow the machine safety standard EN60204-1. This is so that there is consistency and for safety.

In Power Circuits – AC and DC – we have the following color coding;
AC Phase will be BLACK
AC Neutral will be LIGHT BLUE
DC+ will be BLACK
Earth will be GREEN YELLOW

In Control Circuits – AC and DC – we have the following color coding;
AC live will be RED
AC Neutral via transformer will be RED
AC Neutral (mains) will be LIGHT BLUE
DC+ will be BLUE

Interlocks and circuits supplied from remote panels will be ORANGE – in this case, not the one we’re after!

Earth will be GREEN YELLOW

Panel services are 240VAC supplies for panel internal lighting, programming console socket outlet, internal heating & cooling, CPU's (memory backup purposes), etc.

These are 'excepted circuits' as defined in EN60204-1 and as such are not disconnected by the main panel isolator but by a separate isolator mounted inside the panel and designated 'maintained supply'.

The color coding for multicore cables;
Sheath will be ORANGE
AC live cores will be ORANGE
AC neutral cores will be ORANGE
Earth cores will be GREEN YELLOW

Color coding for single-core cables;
AC live will be ORANGE
AC neutral will be LIGHT BLUE
Earth will be GREEN YELLOW

So we come back to the original question…what wires in our panel are orange?

Well, firstly we have the panel internal light. We want to be able to see when we turn the main switch off!

Next, we have the socket. This will allow us to keep our laptop charged up. If the panel needs to be turned off for an extended period of time, then when we are ready to go, our laptop may have died. Not good! The socket is protected by a fuse so that any spikes in power won’t damage our laptop!

The final thing we have in this panel with power is a topic we’ve already covered; the thermostat and cooling fan!

As we’ve already determined, we need to be able to keep the panel cool, even when the main switch is off.

So how does this all work? Well inside the panel, we have the mains feed 3 phase power that comes into the panel to a set of terminals labeled L1, L2, L3, and N.

You can see from this that 1 phase – L1/N –has orange wires in. It is separate from the other wires in this terminal block so that they act independently.

On the back of the main switch on the left-hand door, the wires are identified as L1, L2, L3, and N, matching what we have on the terminals.

The outgoing side of this main switch will be isolated if the switch is off, and will be powered if the switch is on. The main switch is connected to the contactor labeled “150K1”.

When the switch is on, giving power to the panel, this contactor will be “pulled in” or “energized”. Once this is energized, power can be distributed around the rest of the panel.

=============================

=============================

Missed our most recent videos? Watch them here:

=============================

To stay up to date with our last videos and more lessons, make sure to subscribe to this YouTube channel:

=============================

=============================

#RealPars #PLC #ControlPanel

[realpars]

This video references Machine Safety Standard EN 60204-1, which is a European Standard. There are many wiring color schemes in use around the world. The video shows one implementation (EN 60445). Whenever designing or troubleshooting inside a panel, it is imperative to review the documentation, including wiring diagrams, to identify the various circuits in the panel.

In the US, NFPA (NEC) and UL508A are the corresponding standards. In those standards, using orange and white/orange is in both the NFPA 79 and UL 508A for components that remain energized when panel power is disconnected, regardless of potential.

[mwautomatic]

FYI, for anyone looking from the US, this is not a standard for controls in the US.

[colincampbell]

Your videos are awesome, the only caution I would mention in regards to this one is that many facilities have different standards for wiring. I work in a pulp mill that is 60 years old. The mill upgraded various systems and there is still PLC 5 in over half the mill. In Canada we have to follow the Canadian Electrical Code and work within that code to create a mill standard as well.

[PowerHaus]

As an industrial electrician who works on these panels all over the world.
There is no such thing as a standard - even in Europe!

For context my last company wired everything in orange
I have never seen two panels the same- not even close.

[messagetous]

A lot are. I had to reroute several wires in a cabinet that were run in front of the strip. When I threw the main power, I found the wires I was working with were live. It was only 24V so I black taped the tips and ran them through. Also, several contacts and other electrical/electronic, almost half the panel, were still live. I asked around and no one knew. Thanks RealPars.

[davidmaes]

The wires going in and coming out of the main switch have the same name (L1, L2, L3). This is a major error as you may touch the wrong wires elsewhere in the panel after you THINK you disconnected them from the mains. Da's kei-gevaarlijk man!!

[scrappydogfinance]

Wire numbering and tagging and matching wiring diagrams and schematics are most useful and should have a copy inside every cabinet in my opinion. But being able tor recognize the components inside the cabinet and understanding typical power flow and distribution in these control cabinets an experienced well trained technician or automation engineer will be able to identify most components and wire functions regardless of color... Also, use a a good voltmeter and non-contact voltage detector can be very useful in verifying voltage and function of wires in a cabinet also. Good wire and terminal tagging and consistent naming conventions really helps alot and should not be understated in helping workers identify wire functions and conventions being used. Effective Tagging can help a person quickly identify function and voltage type.

[danieltracy]

I am an industrial automation engineer and I don’t think I have ever seen this standard followed by any integrator. I wouldn’t trust it, always use a diagram if you have one, or check it out yourself.

[MiniPeugot]

Don't believe this is how every cabinet is wired. Always read the elementary drawings.

[tiredoldmechanic]

It's interesting how differently various manufacturers and countries use wire colors, wire numbers and set up wiring schematics. Mobile equipment can be quite different from stationary equipment. It can be quite difficult working on equipment constructed in various countries and keeping the differences in mind. In the US, we change the wire number when it connects through a device when other systems will use the same number on a wire in a circuit no matter how many devices it goes through. It's only possible to tell what part of the circuit it's in by checking terminal numbers at each end.

[finnna]

This wiring method must be company specific or country specific. Any cabinet that has power that cant be shut off has to have labeling on the outside telling anyone that shutting off the disconnect will not kill all power in that cabinet.

[MrWirebrain]

I have worked in control panels of CNC machines made from all around the world for over 40 years. This is just one variant of what I have seen. it is very common to have AC in a panel live with the main disconnect in the off position to provide lighting and programming power. Usually black wires are reserved for AC power. And most often you do see white for neutrals or black with a tracer. I think this often depends on where this machine is manufactured.

[Liteg]

Every cabinet from different manufactures I've come across use their own coloring code. In the cabinets I design I use orange wires for externally powered control circuits.

[sinankrikor]

I am a Control panel shop supervisor in USA the code is different, Red= 120AC Live, White = 120AC Neutral, Blue = 24VDC , 0VDC White with blue if PSU grounded and Blue with white if not grounded, Orange = 120VAC before disconnect, White with Orange = 120AC Neutral before disconnect, Blue with Orange = 24VDC before disconnect, Black=480VAC, Black with Orang=480VAC before disconnect, Green/Green with Yalow = Ground, Yalow = safety relay circuit .

[lhr]

On all the machines I have worked on when the main panel switch is turned off the panel no longer has power period . To best of my memory I don't recall any using a for lack of a better term remote disconnect like the one shown . They all had a handle on the outside of the door that had a metal rod to engage the main disconnect when the door is closed . To open the door while the panel is energized you had to override( with a small pin ) that to release the metal rod from the disconnect .

[nimabakhshi]

Hey RealPars, in this example why do you need the contactor? The entire 3-phase is switched on/off with the external disconnect. Is there any other incoming power supply you are controlling with the contactor?

[zenebehagos]

it is very important lecture more than a physical practice, keep sharing of like these lectures, thanks a lot

[richardclark]

Not a standard in the US. Orange is used for 24 VAC . But has been used to signify voltage from a source outside the panel not controlled by the main disconnect on the panel. Yellow is more common for this purpose . And a purple wire used as a jumper wire in a circuit that may be used as a place holder for future input devices.

[sebastiannielsen]

5:50 why would you use a contactor, if the switch is three-phase 5:30 ? Normally, you would either have a three-phase switch feeding the whole load, or a single-phase switch switching a 230v (in this case it would be L2+N if L1+N is used by the maintained supply, and L3+N if L1+N and L2+N is used by some loads - to keep the phases as balanced as possible) that goes to a three-phase isolation-certified contactor with 230v coil.

[johnclarke]

Worked on a old 1970s built control panel this morning which had white wire only and only method of ident was the numbering at each end of the wire. Doubt it will ever get rewired - no interest or budget to do so.